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Laclede Gas Company - Residential High Efficiency Heating Rebate Program |
Energy.gov (U.S. Department of Energy (DOE)) Indexed Site
Residential High Efficiency Heating Rebate Residential High Efficiency Heating Rebate Program Laclede Gas Company - Residential High Efficiency Heating Rebate Program < Back Eligibility Multi-Family Residential Residential Savings Category Heating & Cooling Commercial Heating & Cooling Heating Appliances & Electronics Water Heating Maximum Rebate Heating System: 2 maximum Programmable Thermostats: 2 maximum Multi-Family Property Owners: 50 thermostat rebates, 50 furnace rebates over the life of the program Program Info State Missouri Program Type Utility Rebate Program Rebate Amount Gas Furnace: $150 - $200 Gas Boiler: $150 Programmable Setback Thermostat: $25 Gas Water Heater: $50 - $200 Provider Laclede Gas Company Laclede Gas Company offers various rebates to residential customers for investing in energy efficient equipment and appliances. Residential
Predicting high harmonic ion cyclotron heating efficiency in Tokamak plasmas
SciTech Connect
Observations of improved radio frequency (RF) heating efficiency in high-confinement (H-) mode plasmas on the National Spherical Tokamak Experiment (NSTX) are investigated by whole-device linear simulation. We present the first full-wave simulation to couple kinetic physics of the well confined core plasma to the poorly confined scrape-off plasma. The new simulation is used to scan the launched fast-wave spectrum and examine the steady-state electric wave field structure for experimental scenarios corresponding to both reduced, and improved RF heating efficiency. We find that launching toroidal wave-numbers that required for fast-wave propagation excites large amplitude (kVm 1 ) coaxial standing modes in the wave electric field between the confined plasma density pedestal and conducting vessel wall. Qualitative comparison with measurements of the stored plasma energy suggest these modes are a probable cause of degraded heating efficiency. Also, the H-mode density pedestal and fast-wave cutoff within the confined plasma allow for the excitation of whispering gallery type eigenmodes localised to the plasma edge.
Green, David L [ORNL; Jaeger, E. F. [XCEL; Berry, Lee A [ORNL; Chen, Guangye [ORNL; Ryan, Philip Michael [ORNL; Canik, John [ORNL
High Efficiency Adsorption Chillers: High Efficiency Adsorption Cooling Using Metal Organic Heat Carriers
BEETIT Project: PNNL is incorporating significant improvements in materials that adsorb liquids or gases to design more efficient adsorption chillers. An adsorption chiller is a type of air conditioner that is powered by heat, solar or waste heat, or combustion of natural gas. Unlike typical chillers, this type has few moving parts and uses almost no electricity to operate. PNNL is designing adsorbent materials at the molecular level with at least 3 times higher refrigerant capacity and up to 20 times faster kinetics than adsorbents used in current chillers. By using the new adsorbent, PNNL is able to create a chiller that is significantly smaller, has twice the energy efficiency, and lower costs for materials and assembly time compared to conventional adsorption chillers.
Commercial high efficiency dehumidification systems using heat pipes
An improved heat pipe design using separately connected two-section one-way flow heat pipes with internal microgrooves instead of wicks is described. This design is now commercially available for use to increase the dehumidification capacity of air conditioning systems. The design also includes a method of introducing fresh air into buildings while recovering heat and controlling the humidity of the incoming air. Included are applications and case studies, load calculations and technical data, and installation, operation, and maintenance information.
High Efficiency R-744 Commercial Heat Pump Water Heaters
The project investigated the development and improvement process of a R744 (CO2) commercial heat pump water heater (HPWH) package of approximately 35 kW. The improvement process covered all main components of the system. More specific the heat exchangers (Internal heat exchanger, Evaporator, Gas cooler) as well as the expansion device and the compressor were investigated. In addition, a comparison to a commercially available baseline R134a unit of the same capacity and footprint was made in order to compare performance as well as package size reduction potential.
Elbel, Dr. Stefan W.; Petersen, Michael
Simulation of a High Efficiency Multi-bed Adsorption Heat Pump
Science Conference Proceedings (OSTI)
Attaining high energy efficiency with adsorption heat pumps is challenging due to thermodynamic losses that occur when the sorbent beds are thermally cycled without effective heat recuperation. The multi-bed concept described here effectively transfers heat from beds being cooled to beds being heated, which enables high efficiency in thermally driven heat pumps. A simplified lumped-parameter model and detailed finite element analysis are used to simulate the performance of an ammonia-carbon sorption compressor, which is used to project the overall heat pump coefficient of performance. The effects of bed geometry and number of beds on system performance are explored, and the majority of the performance benefit is obtained with four beds. Results indicate that a COP of 1.24 based on heat input is feasible at AHRI standard test conditions for residential HVAC equipment. When compared on a basis of primary energy input, performance equivalent to SEER 13 or 14 are theoretically attainable with this system.
TeGrotenhuis, Ward E.; Humble, Paul H.; Sweeney, J. B.
Highly-Efficient Thermoelectronic Conversion of Solar Energy and Heat into Electric Power
E-Print Network (OSTI)
Electric power may, in principle, be generated in a highly efficient manner from heat created by focused solar irradiation, chemical combustion, or nuclear decay by means of thermionic energy conversion. As the conversion efficiency of the thermionic process tends to be degraded by electron space charges, the efficiencies of thermionic generators have amounted to only a fraction of those fundamentally possible. We show that this space-charge problem can be resolved by shaping the electric potential distribution of the converter such that the static electron space-charge clouds are transformed into an output current. Although the technical development of practical generators will require further substantial efforts, we conclude that a highly efficient transformation of heat to electric power may well be achieved.
Meir, S; Geballe, T H; Mannhart, J
Electrical heating of soils using high efficiency electrode patterns and power phases
DOE Patents (OSTI)
Powerline-frequency electrical (joule) heating of soils using a high efficiency electrode configuration and power phase arrangement. The electrode configuration consists of several heating or current injection electrodes around the periphery of a volume of soil to be heated, all electrodes being connected to one phase of a multi-phase or a single-phase power system, and a return or extraction electrode or electrodes located inside the volume to be heated being connected to the remaining phases of the multi-phase power system or to the neutral side of the single-phase power source. This electrode configuration and power phase arrangement can be utilized anywhere where powerline frequency soil heating is applicable and thus has many potential uses including removal of volatile organic compounds such as gasoline and tricholorethylene (TCE) from contaminated areas.
Buettner, Harley M. (Livermore, CA)
Development of High Efficiency Carbon Dioxide Commercial Heat Pump Water Heater
Although heat pump water heaters are today widely accepted in both Japan and Europe, where energy costs are high and government incentives for their use exist, acceptance of such products in the US has been limited. While this trend is slowly changing with the introduction of heat pump water heaters into the residential market, but acceptance remains low in the commercial sector. The objective of the presented work is the development of a high efficiency R744 heat pump water heater for commercial applications with effective utilization of the cooling capability for air conditioning and/or refrigeration. The ultimate goal is to achieve total system COP of up to 8. This unit will be targeted at commercial use where some cooling load is typically needed year round, such as restaurants, hotels, nursing homes, and hospitals. This paper presents the performance results from the development of four R744 commercial heat pump water heater packages of approximately 35 kW and comparison to a commercially available baseline R134a unit of the same capacity and footprint. In addition, the influences of an internal heat exchanger and an enhanced evaporator on the system performance are described and recommendations are made for further improvements of the R744 system.
Michael PETERSEN; Chad D. BOWERS; Stefan ELBEL; Pega HRNJAK
Advanced Alloys for Compact, High-Efficiency, High-Temperature Heat-Exchangers
Oak Ridge National Laboratory (ORNL) has conducted research and development for several years which has been focused on the behavior and performance improvements of sheets and foils of various alloys for compact heat-exchangers (recuperators) for advanced microturbines. The performance and reliability of such thin sections are challenged at 650-750 C by fine grain size causing excessive creep, and by moisture effects greatly enhancing oxidation attack in exhaust gas environments. Standard 347 stainless steel has been used successfully at or below 600 C, but has suffered from both of these kinds of degradation at 650 C and above. Alloys have been identified which can have very good properties for such heat-exchangers, especially with careful control of microstructure during processing, including alloy 625, HR120 and the new AL20-25+Nb. These alloys, and the mechanistic understanding behind their behavior, are also applicable to achieving the better heat-exchanger technology needed for fuel cells or other high-temperature, clean-energy applications.
Maziasz, Philip J [ORNL; Pint, Bruce A [ORNL; Shingledecker, John P [ORNL; Evans, Neal D [ORNL; Yamamoto, Yukinori [ORNL; More, Karren Leslie [ORNL; Lara-Curzio, Edgar [ORNL
Efficient Heat Storage Materials: Metallic Composites Phase-Change Materials for High-Temperature Thermal Energy Storage
HEATS Project: MIT is developing efficient heat storage materials for use in solar and nuclear power plants. Heat storage materials are critical to the energy storage process. In solar thermal storage systems, heat can be stored in these materials during the day and released at night�when the sun�s not out�to drive a turbine and produce electricity. In nuclear storage systems, heat can be stored in these materials at night and released to produce electricity during daytime peak-demand hours. MIT is designing nanostructured heat storage materials that can store a large amount of heat per unit mass and volume. To do this, MIT is using phase change materials, which absorb a large amount of latent heat to melt from solid to liquid. MIT�s heat storage materials are designed to melt at high temperatures and conduct heat well�this makes them efficient at storing and releasing heat and enhances the overall efficiency of the thermal storage and energy-generation process. MIT�s low-cost heat storage materials also have a long life cycle, which further enhances their efficiency.
Candidate alloys for cost-effective, high-efficiency, high-temperature compact/foil heat-exchangers
Solid oxide fuel cell (SOFC) and molten carbonate fuel cell (MCFC) systems operate at high temperatures (up to 1000 C and 650 C, respectively), which makes them especially attractive sources for combined heat and power (CHP) cogeneration. However, improvements in the efficiency of heat exchange in these fuel cells require both development and careful processing of advanced cost-effective alloys for use in such high-temperature service conditions. The high-temperature properties of both sheet and foil forms of several alloys being considered for use in compact heat-exchangers (recuperators) have been characterized. Mechanical and creep-rupture testing, oxidation studies, and microstructural studies have been performed on commercially available sheet and foil forms of alloy 347, alloys 625, HR230, HR120, and the new AL20-25+Nb. These studies have led to a mechanistic understanding of the responses of these alloys to anticipated service conditions, and suggest that these alloys developed for gas- and micro-turbine recuperator applications are also suitable for use in fuel cell heat-exchangers. Additional work is still required to achieve foil forms with creep life comparable to thicker-section wrought product forms of the same alloys.
Evans, Neal D [ORNL; Maziasz, Philip J [ORNL; Shingledecker, John P [ORNL; Pint, Bruce A [ORNL; Yamamoto, Yukinori [ORNL
Efficiency of unitary heat pumps
The efficiencies of approximately 500 unitary heat pumps, from 30 different manufacturers, certified by the Air Conditioning and Refrigeration Institute (ARI) were examined. The certified units account for about 90% of all unitary heat pumps manufactured in the U.S. with a rated cooling capacity below 135,000 Btu/hr, and thus represent a comprehensive data file of the efficiencies of unitary heat pumps offered for sale in the U.S. A computer was used to group the heat pumps according to type and capacity, and to calculate their coefficients of performance (COP) using the data contained in ARI current Directory (April 1 to July 31, 1973) of Certified Unitary Heat Pumps. The results show that the COP of the heat pumps varied from a low of 1.5 to a high of 3.15 or a factor of 2 between the lowest and the highest efficiency, and that the average COP was 2.1 in cooling and 2.4 in heating. The variations of COP with heat pump size, type, manufacturer and outdoor temperature are presented.
Nwude, J.K.; Roman, A.J.
Development and Demonstration of a High Efficiency, Rapid Heating, Low NOx Alternative to Conventional Heating of Round Steel Shapes, Steel Substrate (Strip) and Coil Box Transfer Bars
Direct Flame Impingement involves the use of an array of very high-velocity flame jets impinging on a work piece to rapidly heat the work piece. The predominant mode of heat transfer is convection. Because of the locally high rate of heat transfer at the surface of the work piece, the refractory walls and exhaust gases of a DFI furnace are significantly cooler than in conventional radiant heating furnaces, resulting in high thermal efficiency and low NOx emissions. A DFI furnace is composed of a successive arrangement of heating modules through or by which the work piece is conveyed, and can be configured for square, round, flat, and curved metal shapes (e.g., billets, tubes, flat bars, and coiled bars) in single- or multi-stranded applications.
Kurek, Harry; Wagner, John
Demonstration and Performance Monitoring of Foundation Heat Exchangers (FHX) in Ultra-High Energy Efficient Research Homes
DOE Green Energy (OSTI)
The more widespread use of Ground Source Heat Pump (GSHP) systems has been hindered by their high first cost, which is mainly driven by the cost of the drilling and excavation for installation of ground heat exchangers (GHXs). A new foundation heat exchanger (FHX) technology was proposed to reduce first cost by placing the heat exchanger into the excavations made during the course of construction (e.g., the overcut for the basement and/or foundation and run-outs for water supply and the septic field). Since they reduce or eliminate the need for additional drilling or excavation, foundation heat exchangers have the potential to significantly reduce or eliminate the first cost premium associated with GSHPs. Since December 2009, this FHX technology has been demonstrated in two ultra-high energy efficient new research houses in the Tennessee Valley, and the performance data has been closely monitored as well. This paper introduces the FHX technology with the design, construction and demonstration of the FHX and presents performance monitoring results of the FHX after one year of monitoring. The performance monitoring includes hourly maximum and minimum entering water temperature (EWT) in the FHX compared with the typical design range, temperature difference (i.e., T) across the FHX, and hourly heat transfer rate to/from the surrounding soil.
Im, Piljae [ORNL; Hughes, Patrick [ORNL; Liu, Xiaobing [ORNL
High Harmonic Fast Wave Heating Efficiency Enhancemen and Current Drive at Longer Wavelength on the National Spherical Torus Experiment
High harmonic fast wave heating and current drive (CD) are being developed on the National Spherical Torus Experiment (NSTX) [M. Ono et al., Nucl. Fusion 41, 1435 (2001)] for supporting startup and sustainment of the ST plasma. Considerable enhancement of the core heating efficiency (?) from 44% to 65% has been obtained for CD phasing of the antenna (strap-to-strap ? = -90o, k? = -8 m-1) by increasing the magnetic field from 4.5 kG to 5.5 kG. This increase in efficiency is strongly correlated to moving the location of the onset density for perpendicular fast wave propagation (nonset ? ??� k|| 2/w) away from the antenna face and wall, and hence reducing the propagating surface wave fields. RF waves propagating close to the wall at lower B? and k|| can enhance power losses from both the parametric decay instability (PDI) and wave dissipation in sheaths and structures around the machine. The improved efficiency found here is attributed to a reduction in the latter, as PDI losses are little changed at the higher magnetic field. Under these conditions of higher coupling efficiency, initial measurements of localized CD effects have been made and compared with advanced RF code simulations
J. Hosea, R. E. Bell, B.P. LeBlanc, C.K. Phillips, G. Taylor, E. Valeo, J.R. Wilson, E.F. Jaeger, P.M. Ryan, J. Wilgen, H. Yuh, F. Levinton, S. Sabbagh, K. Tritz, J. Parker, P.T. Bonoli, R. Harvey, and the NSTX Team
High Harmonic Fast Wave Heating Efficiency Enhancement and Current Drive at Longer Wavelength on the National Spherical Torus Experiment
High harmonic fast wave heating and current drive CD are being developed on the National Spherical Torus Experiment M. Ono et al., Nucl. Fusion 41, 1435 2001 for supporting startup and sustainment of the spherical torus plasma. Considerable enhancement of the core heating efficiency from 44% to 65% has been obtained for CD phasing of the antenna strap-to-strap = 90 , k= 8 m 1 by increasing the magnetic field from 4.5 to 5.5 kG. This increase in efficiency is strongly correlated to moving the location of the onset density for perpendicular fast wave propagation nonsetBk 2 / away from the antenna face and wall, and hence reducing the propagating surface wave fields. Radio frequency RF waves propagating close to the wall at lower B and k can enhance power losses from both the parametric decay instability PDI and wave dissipation in sheaths and structures around the machine. The improved efficiency found here is attributed to a reduction in the latter, as PDI losses are little changed at the higher magnetic field. Under these conditions of higher coupling efficiency, initial measurements of localized CD effects have been made and compared with advanced RF code simulations.
Hosea, J. [Princeton Plasma Physics Laboratory (PPPL); Bell, R. E. [Princeton Plasma Physics Laboratory (PPPL); LeBlanc, B [Princeton Plasma Physics Laboratory (PPPL); Phillips, Cynthia [Princeton Plasma Physics Laboratory (PPPL); Taylor, G. [Princeton Plasma Physics Laboratory (PPPL); Valeo, Dr Ernest [Princeton Plasma Physics Laboratory (PPPL); Wilson, J. R. [Princeton Plasma Physics Laboratory (PPPL); Jaeger, Erwin Frederick [ORNL; Ryan, Philip Michael [ORNL; Wilgen, John B [ORNL; Yuh, H. [Nova Photonics; Levinton, F. [Fusion Physics and Technology; Sabbagh, S. A. [Columbia University; Tritz, K. [Johns Hopkins University; Parker, J. [Cornell University; Bonoli, P. [Massachusetts Institute of Technology (MIT); Harvey, R. W. [CompX, Del Mar, CA
Energy-efficient water heating
This fact sheet describes how to reduce the amount of hot water used in faucets and showers, automatic dishwashers, and washing machines; how to increase water-heating system efficiency by lowering the water heater thermostat, installing a timer and heat traps, and insulating hot water pipes and the storage tank; and how to use off-peak power to heat water. A resource list for further information is included.
Efficient Electric Technologies for Industrial Heating: Emerging Activities
Industrial process heating is typically accomplished with fossil- and by-product fuels. However, new high-efficiency electric technologies for process heating applications are under development and commercially available, including three efficient electric process heating technologies covered in this Brief: Induction heating and melting Microwave (MW) heating, drying and curing Radio frequency (RF) heating, drying, and curing These technologies were selected for three reasons. First, in each case there a...
EnergyUnited - Residential Energy Efficient Heat Pump Rebate Program |
EnergyUnited - Residential Energy Efficient Heat Pump Rebate EnergyUnited - Residential Energy Efficient Heat Pump Rebate Program EnergyUnited - Residential Energy Efficient Heat Pump Rebate Program < Back Eligibility Residential Savings Category Heating & Cooling Commercial Heating & Cooling Heat Pumps Maximum Rebate 2 per dwelling Program Info State North Carolina Program Type Utility Rebate Program Rebate Amount Heat Pumps (14 SEER): $150 Heat Pumps (15 SEER +): $300 Provider EnergyUnited EnergyUnited offers rebates to residential customers who upgrade to high efficiency heat pumps. Rebates range from $150 - $300, varying by efficiency. The rebate form can be found on the program website and must be completed by the installing HVAC contractor. Each unit will require a separate form in order to qualify for rebates. Systems must be
Thermodynamic Efficiency of Heat Exchange Devices
The continued rise in the cost of energy 'has it imperative to augment the usual heat flow analyses for power plants, refineries, chemical plants and other energy intensive industries by adding analyses of available energy flow and device irreversibilities. The reclamation of what was formerly 'waste heat' by using additional, or more efficient, equipment has become not only economically feasible, but sometimes essential. A thermodynamic efficiency based on the second law of thermodynamics is defined for heat exchange devices. The efficiency can be simply written in terms of the mean absolute temperature levels of the two fluids exchanging heat, and an appropriate environment temperature. It is also shown that for a given ratio of hot to cold inlet temperatures, the efficiency and effectiveness for particular heat exchange configurations are related. Conclusions regarding the effect of stream temperatures on the efficiency of various types of exchangers are made. The concept is applied to typical heat exchange cases to demonstrate its applicability and sensitivity.
Witte, L. C.; Shamsundar, N.
High Efficiency Integrated Space Conditioning, Water Heating and Air Distribution System for HUD-Code Manufactured Housing
Recognizing the need for new space conditioning and water heating systems for manufactured housing, DeLima Associates assembled a team to develop a space conditioning system that would enhance comfort conditions while also reducing energy usage at the systems level. The product, Comboflair® was defined as a result of a needs analysis of project sponsors and industry stakeholders. An integrated system would be developed that would combine a packaged airconditioning system with a small-duct, high-velocity air distribution system. In its basic configuration, the source for space heating would be a gas water heater. The complete system would be installed at the manufactured home factory and would require no site installation work at the homesite as is now required with conventional split-system air conditioners. Several prototypes were fabricated and tested before a field test unit was completed in October 2005. The Comboflair® system, complete with ductwork, was installed in a 1,984 square feet, double-wide manufactured home built by Palm Harbor Homes in Austin, TX. After the home was transported and installed at a Palm Harbor dealer lot in Austin, TX, a data acquisition system was installed for remote data collection. Over 60 parameters were continuously monitored and measurements were transmitted to a remote site every 15 minutes for performance analysis. The Comboflair® system was field tested from February 2006 until April 2007. The cooling system performed in accordance with the design specifications. The heating system initially could not provide the needed capacity at peak heating conditions until the water heater was replaced with a higher capacity standard water heater. All system comfort goals were then met. As a result of field testing, we have identified improvements to be made to specific components for incorporation into production models. The Comboflair® system will be manufactured by Unico, Inc. at their new production facility in St. Louis, MO. The product will be initially launched in the hot-humid climates of the southern U.S.
Henry DeLima; Joe Akin; Joseph Pietsch
Field Test of High Efficiency Residential Buildings with Ground-source and Air-source Heat Pump Systems
This paper describes the field performance of space conditioning and water heating equipment in four single-family residential structures with advanced thermal envelopes. Each structure features a different, advanced thermal envelope design: structural insulated panel (SIP); optimum value framing (OVF); insulation with embedded phase change materials (PCM) for thermal storage; and exterior insulation finish system (EIFS). Three of the homes feature ground-source heat pumps (GSHPs) for space conditioning and water heating while the fourth has a two-capacity air-source heat pump (ASHP) and a heat pump water heater (HPWH). Two of the GCHP-equipped homes feature horizontal ground heat exchange (GHX) loops that utillize the existing foundation and utility service trenches while the third features a vertical borehole with vertical u-tube GHX. All of the houses were operated under the same simulated occupancy conditions. Operational data on the house HVAC/Water heating (WH) systems are presented and factors influencing overall performance are summarized.
Ally, Moonis Raza [ORNL; Munk, Jeffrey D [ORNL; Baxter, Van D [ORNL
Liquid Metal, a Heat Transport Fluid for High Temperature Solar ...
The need for high efficiency and direct heat conversion into hydrogen, process heat and energy storage pushes the temperature for solar concentrator systems.
Promotion of efficient heat pumps for heating (ProHeatPump)
and towns have (some) district heating, and DH currently supplies 1% of heating for buildings in Norway.2 to district heating if there is a supply. According to HP industry representatives, howeverProject Promotion of efficient heat pumps for heating (ProHeatPump) EIE/06/072 / S12
Heat Pump for High School Heat Recovery
The heat pump system used for recycling and reusing waste heat in s high school bathroom was minutely analyzed in its coefficient of performance, onetime utilization ratio of energy, economic property and so on. The results showed that this system has good economic property, can conserve energy and protects the environment. Therefore, there is a large potential for its development. In addition, three projects using this system are presented and contrasted, which indicate that a joint system that uses both the heat pump and heat exchanger to recycle waste heat is a preferable option.
Huang, K.; Wang, H.; Zhou, X.
High Efficiency, Clean Combustion
Energy use in trucks has been increasing at a faster rate than that of automobiles within the U.S. transportation sector. According to the Energy Information Administration (EIA) Annual Energy Outlook (AEO), a 23% increase in fuel consumption for the U.S. heavy duty truck segment is expected between 2009 to 2020. The heavy duty vehicle oil consumption is projected to grow between 2009 and 2050 while light duty vehicle (LDV) fuel consumption will eventually experience a decrease. By 2050, the oil consumption rate by LDVs is anticipated to decrease below 2009 levels due to CAFE standards and biofuel use. In contrast, the heavy duty oil consumption rate is anticipated to double. The increasing trend in oil consumption for heavy trucks is linked to the vitality, security, and growth of the U.S. economy. An essential part of a stable and vibrant U.S. economy is a productive U.S. trucking industry. Studies have shown that the U.S. gross domestic product (GDP) is strongly correlated to freight transport. Over 90% of all U.S. freight tonnage is transported by diesel power and over 75% is transported by trucks. Given the vital role that the trucking industry plays in the economy, improving the efficiency of the transportation of goods was a central focus of the Cummins High Efficient Clean Combustion (HECC) program. In a commercial vehicle, the diesel engine remains the largest source of fuel efficiency loss, but remains the greatest opportunity for fuel efficiency improvements. In addition to reducing oil consumption and the dependency on foreign oil, this project will mitigate the impact on the environment by meeting US EPA 2010 emissions regulations. Innovation is a key element in sustaining a U.S. trucking industry that is competitive in global markets. Unlike passenger vehicles, the trucking industry cannot simply downsize the vehicle and still transport the freight with improved efficiency. The truck manufacturing and supporting industries are faced with numerous challenges to reduce oil consumption and greenhouse gases, meet stringent emissions regulations, provide customer value, and improve safety. The HECC program successfully reduced engine fuel consumption and greenhouse gases while providing greater customer valve. The US EPA 2010 emissions standard poses a significant challenge for developing clean diesel powertrains that meet the DoE Vehicle Technologies Multi-Year Program Plan (MYPP) for fuel efficiency improvement while remaining affordable. Along with exhaust emissions, an emphasis on heavy duty vehicle fuel efficiency is being driven by increased energy costs as well as the potential regulation of greenhouse gases. An important element of the success of meeting emissions while significantly improving efficiency is leveraging Cummins component technologies such as fuel injection equipment, aftertreatment, turbomahcinery, electronic controls, and combustion systems. Innovation in component technology coupled with system integration is enabling Cummins to move forward with the development of high efficiency clean diesel products with a long term goal of reaching a 55% peak brake thermal efficiency for the engine plus aftertreatment system. The first step in developing high efficiency clean products has been supported by the DoE co-sponsored HECC program. The objectives of the HECC program are: (1) To design and develop advanced diesel engine architectures capable of achieving US EPA 2010 emission regulations while improving the brake thermal efficiency by 10% compared to the baseline (a state of the art 2007 production diesel engine). (2) To design and develop components and subsystems (fuel systems, air handling, controls, etc) to enable construction and development of multi-cylinder engines. (3) To perform an assessment of the commercial viability of the newly developed engine technology. (4) To specify fuel properties conducive to improvements in emissions, reliability, and fuel efficiency for engines using high-efficiency clean combustion (HECC) technologies. To demonstrate the technology is compatible with B2
Donald Stanton
Evaluation of high-efficiency heat-transfer techniques. Final report, 27 September 1978-30 September 1981
Single enhanced boiling tubes perform up to an order of magnitude better than single plain tubes, depending strongly on the type of surface and physical properties and operating conditions of the liquid. It is most pronounced at low temperature differences, then decreases and eventually disappears with increase of the temperature difference. The heat flux for a plain tube bundle is considerably greater than that for a single plain tube. Enhanced and finned tube bundles produce appreciable augmentation in heat flux compared to an identical plain tube bundle. The effect usually has most practical significance at low ..delta..T. The augmentation for enhanced tube bundles is less than the augmentation for single tubes, due mainly to the relatively more pronounced convective transfer for plain tubes. Although the cost of enhanced tubes is always higher, their advantage lies not only in smaller units required but, most importantly, that enhanced tubes will produce nucleate boiling at very low temperature differences where plain tubes would not. (Thus, heat recovery is possible in cases which otherwise would have to be rejected). The advantages of enhanced boiling tubes are not only in smaller size of the exchangers, but, in process loops involving compressors, operation of the typical low temperature boiler/condenser at a lower temperature difference, thus resulting in substantial savings in compressor size and energy consumption. Increased application of enhanced boiling surfaces will be realized as less expensive techniques of manufacture become commercially available. Three abstracts are entered separately.
Yilmaz, S.; Palen, J.W.; Taborek, J.
High Efficiency Engine Technologies Program
Caterpillar's Product Development and Global Technology Division carried out a research program on waste heat recovery with support from DOE (Department of Energy) and the DOE National Energy Technology Laboratory. The objective of the program was to develop a new air management and exhaust energy recovery system that would demonstrate a minimum 10% improvement in thermal efficiency over a base heavy-duty on-highway diesel truck engine. The base engine for this program was a 2007 C15 15.2L series-turbocharged on-highway truck engine with a LPL (low-pressure loop) exhaust recirculation system. The focus of the program was on the development of high efficiency turbomachinery and a high efficiency turbocompound waste heat recovery system. The focus of each area of development was as follows: (1) For turbine stages, the focus was on investigation and development of technologies that would improve on-engine exhaust energy utilization compared to the conventional radial turbines in widespread use today. (2) For compressor stages, the focus was on investigating compressor wheel design parameters beyond the range typically utilized in production, to determine the potential efficiency benefits thereof. (3) For turbocompound, the focus was on the development of a robust bearing system that would provide higher bearing efficiencies compared to systems used in turbocompound power turbines in production. None of the turbocharger technologies investigated involved addition of moving parts, actuators, or exotic materials, thereby increasing the likelihood of a favorable cost-value tradeoff for each technology. And the turbocompound system requires less hardware addition than competing bottoming cycle technologies, making it a more attractive solution from a cost and packaging standpoint. Main outcomes of the program are as follows: (1) Two turbine technologies that demonstrated up to 6% improvement in turbine efficiency on gas stand and 1-3% improvement in thermal efficiency in on-engine testing. (2) A compressor technology that demonstrated 1.5% improvement in compressor efficiency on gas stand compared to production available compressors. (3) A power turbine with high efficiency bearing system that demonstrated excellent rotordynamic stability throughout the required speed range, up to 60,000 rpm. (4) A predicted improvement (using engine simulation) in engine thermal efficiency of 7% at the peak torque design point, when combining the technologies developed in this program.
Rich Kruiswyk
PECO Energy (Gas) � Heating Efficiency Rebate Program
Energy.gov (U.S. Department of Energy (DOE))
The PECO Smart Gas Efficiency Upgrade Program offers rebates and incentives to commercial or residential customers that install an ENERGY STAR qualified high-efficiency natural gas furnace or...
Enabling High Efficiency Ethanol Engines
Delphi Automotive Systems and ORNL established this CRADA to explore the potential to improve the energy efficiency of spark-ignited engines operating on ethanol-gasoline blends. By taking advantage of the fuel properties of ethanol, such as high compression ratio and high latent heat of vaporization, it is possible to increase efficiency with ethanol blends. Increasing the efficiency with ethanol-containing blends aims to remove a market barrier of reduced fuel economy with E85 fuel blends, which is currently about 30% lower than with petroleum-derived gasoline. The same or higher engine efficiency is achieved with E85, and the reduction in fuel economy is due to the lower energy density of E85. By making ethanol-blends more efficient, the fuel economy gap between gasoline and E85 can be reduced. In the partnership between Delphi and ORNL, each organization brought a unique and complementary set of skills to the project. Delphi has extensive knowledge and experience in powertrain components and subsystems as well as overcoming real-world implementation barriers. ORNL has extensive knowledge and expertise in non-traditional fuels and improving engine system efficiency for the next generation of internal combustion engines. Partnering to combine these knowledge bases was essential towards making progress to reducing the fuel economy gap between gasoline and E85. ORNL and Delphi maintained strong collaboration throughout the project. Meetings were held regularly, usually on a bi-weekly basis, with additional reports, presentations, and meetings as necessary to maintain progress. Delphi provided substantial hardware support to the project by providing components for the single-cylinder engine experiments, engineering support for hardware modifications, guidance for operational strategies on engine research, and hardware support by providing a flexible multi-cylinder engine to be used for optimizing engine efficiency with ethanol-containing fuels.
Szybist, J.; Confer, K. (Delphi Automotive Systems)
Boiler efficiency methodology for solar heat applications
This report contains a summary of boiler efficiency measurements which can be applied to evaluate the performance of steam-generating boilers via both the direct and indirect methods. This methodology was written to assist industries in calculating the boiler efficiency for determining the applicability and value of thermal industrial heat, as part of the efforts of the Solar Thermal Design Assistance Center (STDAC) funded by Sandia National Laboratories. Tables of combustion efficiencies are enclosed as functions of stack temperatures and the amount of carbon dioxide and carbon monoxide in the gas stream.
Maples, D.; Conwell, J.C. [Louisiana State Univ., Baton Rouge, LA (United States). Boiler Efficiency Inst.; Pacheco, J.E. [Sandia National Labs., Albuquerque, NM (United States)
Heating, Ventilation and Air Conditioning Efficiency
Presented By: WALTER E. JOHNSTON, PE Presented By: WALTER E. JOHNSTON, PE CEM, CEA, CLEP, CDSM, CPE Heating, Ventilation and Air Conditioning (HVAC) system is to provide and maintain a comfortable environment within a building for the occupants or for the process being conducted Many HVAC systems were not designed with energy efficiency as one of the design factors 3 Air Air is the major conductor of heat. Lack of heat = air conditioning OR 4 Btu - Amount of heat required to raise one pound of water 1 F = 0.252 KgCal 1 Pound of Water = About 1 Pint of Water ~ 1 Large Glass 1 Kitchen Match Basics of Air Conditioning = 1 Btu 5 = 6 Low Cost Cooling Unit 7 8 Typical Design Conditions 75 degrees F temperature 50% relative humidity 30 - 50 FPM air movement
High efficiency photoionization detector
A high efficiency photoionization detector is described using tetraaminoethylenes in a gaseous state having a low ionization potential and a relative photoionization cross section which closely matches the emission spectrum of xenon gas. Imaging proportional counters are also disclosed using the novel photoionization detector of the invention. The compound of greatest interest is TMAE which comprises tetrakis(dimethylamino)ethylene which has a measured ionization potential of 5.36 [+-] 0.02 eV, and a vapor pressure of 0.35 torr at 20 C. 6 figs.
Anderson, D.F.
A high efficiency photoionization detector using tetraaminoethylenes in a gaseous state having a low ionization potential and a relative photoionization cross section which closely matches the emission spectrum of xenon gas. Imaging proportional counters are also disclosed using the novel photoionization detector of the invention. The compound of greatest interest is TMAE which comprises tetrakis(dimethylamino)ethylene which has a measured ionization potential of 5.36.+-.0.02 eV, and a vapor pressure of 0.35 torr at 20.degree. C.
Anderson, David F. (3055 Trinity, Los Alamos, NM 87544)
High efficiency shale oil recovery
The overall project objective is to demonstrate the high efficiency of the Adams Counter-Current shale oil recovery process. The efficiency will first be demonstrated on a small scale, in the current phase, after which the demonstration will be extended to the operation of a small pilot plant. Thus the immediate project objective is to obtain data on oil shale retorting operations in a small batch rotary kiln that will be representative of operations in the proposed continuous process pilot plant. Although an oil shale batch sample is sealed in the batch kiln from the start until the end of the run, the process conditions for the batch are the same as the conditions that an element of oil shale would encounter in a continuous process kiln. Similar chemical and physical conditions (heating, mixing, pyrolysis, oxidation) exist in both systems.The two most important data objectives in this phase of the project are to demonstrate (1) that the heat recovery projected for this project is reasonable and (2) that an oil shale kiln will run well and not plug up due to sticking and agglomeration. The following was completed this quarter. (1) Twelve pyrolysis runs were made on five different oil shales. All of the runs exhibited a complete absence of any plugging, tendency. Heat transfer for Green River oil shale in the rotary kiln was 84.6 Btu/hr/ft[sup 2]/[degrees]F, and this will provide for ample heat exchange in the Adams kiln. (2) One retorted residue sample was oxidized at 1000[degrees]F. Preliminary indications are that the ash of this run appears to have been completely oxidized. (3) Further minor equipment repairs and improvements were required during the course of the several runs.
Adams, D.C.
This project investigated an efficient and low cost method of auto-thermally reforming natural gas to hydrogen and carbon monoxide. Reforming is the highest cost step in producing products such as methanol and Fisher Tropsch liquids (i.e., gas to liquids); and reducing the cost of reforming is the key to reducing the cost of these products. Steam reforming is expensive because of the high cost of the high nickel alloy reforming tubes (i.e., indirectly fired reforming tubes). Conventional auto-thermal or Partial Oxidation (POX) reforming minimizes the size and cost of the reformers and provides a near optimum mixture of CO and hydrogen. However POX requires pure oxygen, which consumes power and significantly increases the cost to reforming. Our high efficiency process extracts oxygen from low-pressure air with novel oxygen sorbent and transfers the oxygen to a nickel-catalyzed reformer. The syngas is generated at process pressure (typically 20 to 40 bar) without nitrogen dilution and has a 1CO to 2H{sub 2} ratio that is near optimum for the subsequent production of Fisher-Tropsch liquid to liquids and other chemicals (i.e., Gas to Liquids, GTL). Our high process efficiency comes from the way we transfer the oxygen into the reformer. All of the components of the process, except for the oxygen sorbent, are commonly used in commercial practice. A process based on a longlived, regenerable, oxygen transfer sorbent could substantially reduce the cost of natural gas reforming to syngas. Lower cost syngas (CO + 2H{sub 2}) that is the feedstock for GTL would reduce the cost of GTL and for other commercial applications (e.g., methanol, other organic chemicals). The vast gas resources of Alaska's North Slope (ANS) offer more than 22 Tcf of gas and GTL production in this application alone, and could account for as much as 300,000 to 700,000 bpd for 20 to 30+ years. We developed a new sorbent, which is an essential part of the High Efficiency Oxygen Process (HOP). We tested the sorbent and observed that it has both a good oxygen capacity and operates as a highly effective reforming catalyst. We conducted a long duration tests of the sorbent (1,500 hours of continuous operation in the HOP cycle). Although the sorbent lost some oxygen capacity with cycling, the sorbent oxygen capacity stabilized after 1,000 hours and remained constant to the end of the test, 1,500 hour. The activity of the catalyst to reform methane to a hydrogen and carbon monoxide mixture was unchanged through the oxidation/reduction cycling. Our cost and performance analyses indicated a significant reduction in the cost of GTL production when using the HOP process integrated into a GTL plant.
Robert J. Copeland; Yevgenia Gershanovich; Brian Windecker
High Efficiency Steam Electrolyzer
A novel steam electrolyzer has been developed. In conventional electrolyzers, oxygen produced from electrolysis is usually released in the air stream. In their novel design, natural gas is used to replace air in order to reduce the chemical potential difference across the electrolyzer, thus minimizing the electrical consumption. The oxygen from the electrolysis is consumed in either a total oxidation or a partial oxidation reaction with natural gas. Experiments performed on single cells shown a voltage reduction as much as 1 V when compared to conventional electrolyzers. Using thin film materials and high performance cathode and anode, electrolysis could be done at temperatures as low as 700 C with electrolytic current as high as 1 A/cm{sup 2} at a voltage of 0.5 V only. The 700 C operating temperature is favorable to the total oxidation of natural gas while minimizing the need for steam that is otherwise necessary to avoid carbon deposition. A novel tubular electrolyzer stack has been developed. The system was designed to produce hydrogen at high pressures, taking advantage of the simplicity and high efficiency of the electrochemical compressors. A complete fabrication process was developed for making electrolyzer tubes with thin film coatings. A 100 W stack is being built.
Pham, A.Q.
Using Plate Heat Exchangers to Increase Energy Efficiency
"In recent years, there has been an increasing awareness of Plate Heat Exchangers (PHE's) in industrial processes around the world. While PHE's have historically been classified as compact heat exchangers, compactness is often a secondary advantage that makes them well suited for retrofit applications in process plants that are often space limited. The primary advantage of PHE's are their high efficiency, flexibility, and reliability. Because of their efficiency, PHE's are being used in more applications where shell and tube heat exchangers were historically used. The high efficiency of the PHE offers the greatest benefits to the process industries. The countercurrent flow configuration, high heat transfer coefficients, and low fouling tendencies result in a heat exchanger that is extremely economical and efficient, especially in energy recovery applications where low LMTD's are common. This paper will review PHE design and construction and show how PHE's can be used to recover energy in many industrial processes. An economical analysis will be included to show the competitiveness of PHE's in energy recovery applications. The paper will review the advantages, benefits, and limitations of PHE's. Recent advances in PHE technology will also be discussed. "
Bailey, K.
The overall project objective is to demonstrate the high efficiency of the Adams Counter-Current shale oil recovery process. The efficiency will first be demonstrated on a small scale, in the current phase, after which the demonstration will be extended to the operation of a small pilot plant. Thus the immediate project objective is to obtain data on oil shale retorting operations in a small batch rotary kiln that will be representative of operations in the proposed continuous process pilot plant. Although an oil shale batch sample is sealed in the batch kiln from the start until the end of the run, the process conditions for the batch are the same as the conditions that an element of oil shale would encounter in a continuous process kiln. Similar chemical and physical (heating, mixing) conditions exist in both systems. The two most important data objectives in this phase of the project are to demonstrate (1) that the heat recovery projected for this project is reasonable and (2) that an oil shale kiln will run well and not plug up due to sticking and agglomeration. The following was completed and is reported on this quarter: (1) A software routine was written to eliminate intermittently inaccurate temperature readings. (2) We completed the quartz sand calibration runs, resolving calibration questions from the 3rd quarter. (3) We also made low temperature retorting runs to identify the need for certain kiln modifications and kiln modifications were completed. (4) Heat Conductance data on two Pyrolysis runs were completed on two samples of Occidental oil shale.
High efficiency Brayton cycles using LNG
A modified, closed-loop Brayton cycle power conversion system that uses liquefied natural gas as the cold heat sink media. When combined with a helium gas cooled nuclear reactor, achievable efficiency can approach 68 76% (as compared to 35% for conventional steam cycle power cooled by air or water). A superheater heat exchanger can be used to exchange heat from a side-stream of hot helium gas split-off from the primary helium coolant loop to post-heat vaporized natural gas exiting from low and high-pressure coolers. The superheater raises the exit temperature of the natural gas to close to room temperature, which makes the gas more attractive to sell on the open market. An additional benefit is significantly reduced costs of a LNG revaporization plant, since the nuclear reactor provides the heat for vaporization instead of burning a portion of the LNG to provide the heat.
Morrow, Charles W. (Albuquerque, NM)
High efficiency solar heater
This patent describes a solar oven comprising canted side-walls defining a heating chamber of inverted pyramidal configuration having a rectangular upper aperture for admitting solar radiation into the chamber, and a closed bottom, the side walls having four blackened non-reflective interior surfaces and translucent means closing the upper aperture for containing heated air with the chamber. The four interior surfaces are exposed to radiation entering the chamber through the translucent means. A frusto-pyramidal reflector is removably mounted externally of the heating chamber and including four reflector surfaces diverging from each other at a somewhat greater angle than the interior surfaces such that light falling onto the external reflector substantially normally to the translucent means is reflected onto an opposite one of the interior surfaces substantially at right angles thereto; and temperature responsive means arranged for opening a vent into the chamber in response to temperature rising in the chamber beyond a predetermined level. The temperature responsive means comprises spring means retained in a compressed state by structural means selected to lose structural integrity near the predetermined level. The spring means is released upon the structural means losing structural integrity near the predetermined level and failing under load imposed by the spring means, whereby the spring means is free to operate to open the vent.
Varney, J.A.; Varney, F.M.
High Temperature Heat Exchanger Project
The UNLV Research Foundation assembled a research consortium for high temperature heat exchanger design and materials compatibility and performance comprised of university and private industry partners under the auspices of the US DOE-NE Nuclear Hydrogen Initiative in October 2003. The objectives of the consortium were to conduct investigations of candidate materials for high temperature heat exchanger componets in hydrogen production processes and design and perform prototypical testing of heat exchangers. The initial research of the consortium focused on the intermediate heat exchanger (located between the nuclear reactor and hydrogen production plan) and the components for the hydrogen iodine decomposition process and sulfuric acid decomposition process. These heat exchanger components were deemed the most challenging from a materials performance and compatibility perspective
Anthony E. Hechanova, Ph.D.
An Analysis of Efficiency Improvements in Residential Sized Heat Pumps
The objectives of this study included: (1) development of classes of heat pumps, (2) evaluation and selection of a suitable heat pump design model, (3) characterization of suitable baseline heat pump designs, (4) selection of design options that can be used to improve heat pump efficiency, and (5) development of heat pump designs to cover the whole spectrum of efficiencies available today and those that may be technologically feasible in the next few years.
O'Neal, D. L.; Boecker, C. L.; Murphy, W. E.; Notman, J. R.
Efficiency of Steam and Hot Water Heat Distribution Systems
Efficiency of Steam and Hot Water Heat Distribution Systems Gary Phetteplace September 1995- tion medium (steam or hot water) and temperature for heat distribution systems. The report discusses the efficiency of both steam and hot water heat distribution systems in more detail. The results of several field
The overall project objective is to demonstrate the high efficiency of the Adams Counter-Current shale oil recovery process. The efficiency will first be demonstrated at bench-scale, in the current phase, after which the demonstration will be extended to the operation of a small pilot plant. Thus the immediate project objective is to obtain data on oil shale retorting operations in a small batch rotary kiln that will be representative of operations in the proposed continuous process pilot plant. Although a batch oil shale sample will be sealed in the batch kiln from the start until the end of the run, the process conditions for the batch will be the same as the conditions that an element of oil shale would encounter in a large continuous process kiln. For example, similar conditions of heat-up rate (20 deg F/min during the pyrolysis), oxidation of the residue and cool-down will prevail for the element in both systems. This batch kiln is a unit constructed in a 1987 Phase I SBIR tar sand retorting project. The kiln worked fairly well in that project; however, the need for certain modifications was observed. These modifications are now underway to simplify the operation and make the data and analysis more exact. The agenda for the first three months of the project consisted of the first of nine tasks and was specified as the following four items: 1. Sample acquisition and equipment alteration: Obtain seven oil shale samples, of varying grade each 10 lb or more, and samples of quartz sand. Order equipment for kiln modification. 3. Set up and modify kiln for operation, including electric heaters on the ends of the kiln. 4. Connect data logger and make other repairs and changes in rotary batch kiln.
Field Measurements of Heating System Efficiency in Nine Electrically-Heated Manufactured Homes.
This report presents the results of field measurements of heating efficiency performed on nine manufactured homes sited in the Pacific Northwest. The testing procedure collects real-time data on heating system energy use and heating zone temperatures, allowing direct calculation of heating system efficiency.
Davis, Bob; Siegel, J.; Palmiter, L.; Baylon, D.
Heat exchanger efficiently operable alternatively as evaporator or condenser
A heat exchanger adapted for efficient operation alternatively as evaporator or condenser and characterized by flexible outer tube having a plurality of inner conduits and check valves sealingly disposed within the outer tube and connected with respective inlet and outlet master flow conduits and configured so as to define a parallel flow path for a first fluid such as a refrigerant when flowed in one direction and to define a serpentine and series flow path for the first fluid when flowed in the opposite direction. The flexible outer tube has a heat exchange fluid, such as water, flowed therethrough by way of suitable inlet and outlet connections. The inner conduits and check valves form a package that is twistable so as to define a spiral annular flow path within the flexible outer tube for the heat exchange fluid. The inner conduits have thin walls of highly efficient heat transfer material for transferring heat between the first and second fluids. Also disclosed are specific materials and configurations.
Ecker, Amir L. (Dallas, TX)
Efficient numerical modeling of borehole heat exchangers
This paper presents a finite element modeling technique for double U-tube borehole heat exchangers (BHE) and the surrounding soil mass. Focus is placed on presenting numerical analyses describing the capability of a BHE model, previously reported, to ... Keywords: BHE, Geothermal heat pumps, Geothermic, Heat transfer, Space heating
R. Al-Khoury; T. K�lbel; R. Schramedei
Development of Technologies on Innovative Simplified Nuclear Power Plant Using High-Efficiency Steam Injectors (10) Application to a Small District-Heating Reactor
A steam injector (SI) is a simple, compact and passive pump and also acts as a high-performance direct-contact compact heater. This provides SI with capability to use as a passive ECCS pump and also as a direct-contact feedwater heater that heats up feedwater by using extracted steam from the turbine. In order to develop a high reliability passive ECCS pump and a compact feedwater heater, it is necessary to quantify the characteristics between physical properties of the flow field. We carried out experiments to observe the internal behavior of the water jet as well as measure the velocity of steam jet using a laser Doppler velocimetry. Its performance depends on the phenomena of steam condensation onto the water jet surface and heat transfer in the water jet due to turbulence on to the phase-interface. The analysis was also conducted by using a CFD code with the separate two-phase flow models. With regard to the simplified feed-water system, size of four-stage SI system is almost the same as the model SI that had done the steam and water test that pressures were same as that of current ABWR. The authors also conducted the hot water supply system test in the snow for a district heating. With regard to the SI core cooling system, the performance tests results showed that the low-pressure SI core cooling system will decrease the PCT to almost the same as the saturation temperature of the steam pressure in a pressure vessel. As it is compact equipment, SI is expected to bring about great simplification and materials-saving effects, while its simple structure ensures high reliability of its operation, thereby greatly contributing to the simplification of the power plant for not only an ABWR power plant but also a small PWR/ BWR for district heating system. (authors)
Tadashi Narabayashi; Yoichiro Shimadu; Toshiiro Murase; Masatoshi Nagai [Hokkaido University, Kita-ku, Sapporo (Japan); Michitsugu Mori; Shuichi Ohmori [Tokyo Electric Power Company (Japan)
Northwest Energy Efficiency Alliance - Smart Water Heat Rebate Program
Northwest Energy Efficiency Alliance - Smart Water Heat Rebate Northwest Energy Efficiency Alliance - Smart Water Heat Rebate Program (Washington) Northwest Energy Efficiency Alliance - Smart Water Heat Rebate Program (Washington) < Back Eligibility Residential Savings Category Appliances & Electronics Water Heating Program Info Start Date 05/01/2012 State District of Columbia Program Type Non-Profit Rebate Program Provider Northwest Energy Efficiency Project The Northwest Energy Efficiency Alliance (NEEA) is offering a rebate program for homeowners who purchase and install an eligible heat pump water heater. A rebate of $750 is offered for qualifying heat pump water heater units. New units must replace an existing electric water heater and must be installed by a Smart Water Heat oriented contractor. New construction is
Piedmont EMC- Residential Energy Efficient Heat Pump Rebate Program
Piedmont Electric Membership Corporation (PEMC) offers a financial incentive for residential members to install energy efficient heat pumps and compact fluorescent lighting in eligible homes....
Northwest Energy Efficiency Alliance - Smart Water Heat Rebate...
The Northwest Energy Efficiency Alliance (NEEA) is offering a rebate program for homeowners who purchase and install an eligible heat pump water heater. A rebate of 750 is...
High Efficiency Particulate Air Filters
NLE Websites -- All DOE Office Websites (Extended Search)
High Efficiency Particulate Air (HEPA) Filters High Efficiency Particulate Air (HEPA) Filters Home Standards DOE Workshops Nuclear Air Cleaning Conference Proceedings Qualified Filter List News Items Related Sites HEPA Related Lessons Learned Contact Us HSS Logo High Efficiency Particulate Air Filters The HEPA Filter web site provides a forum for informing and reporting department-wide activities related to filtration and ventilation issues with special reference to the High Efficiency Particulate Air (HEPA) Filters' use, inspection, and testing. This site contains essentials of DOE HEPA filter test program, procedures, requirements and quality assurance aspects applicable to HEPA filters used in DOE facilities. This site contains information about the DOE-accepted Filter Test Facility and its management, operation and quality assuranceprogram.
Efficient, Low-cost Microchannel Heat Exchanger
? Buildings (chillers, cooling towers, heat pump water heaters) ... ? Renewable energy (concentrated solar power, residential solar hot water,
Union Power Cooperative - Residential Energy Efficient Heat Pump Loan
Union Power Cooperative - Residential Energy Efficient Heat Pump Union Power Cooperative - Residential Energy Efficient Heat Pump Loan Program Union Power Cooperative - Residential Energy Efficient Heat Pump Loan Program < Back Eligibility Residential Savings Category Heating & Cooling Commercial Heating & Cooling Heat Pumps Maximum Rebate $7,500 Program Info State North Carolina Program Type Utility Loan Program Rebate Amount up to $7,500 Provider Union Power Cooperative Union Power Cooperative offers low interest loans to help its residential customers finance new, energy-efficient heat pumps. Interest rates, currently at 9%, will be fixed for the term of the loan. Loans can be up to $7,500 over five years. Customers pay back the loan with payments on monthly electric bills. There is a one time loan filing fee of $42. Contact
Efficiency Maine - Replacement Heating Equipment Program (Maine...
Open Energy Info (EERE)
announced its closure November 2011. According to Efficiency Maine, almost 2,600 homeowners participated in the program trading in older, less-efficient space andor water...
High-Efficiency Steam Electrolyzer
We are developing a novel high-efficiency, high-temperature steam electrolyzer. Although water or steam electrolysis is well known to be one of the cleanest ways to produce hydrogen, widespread utilization is hindered by high operational costs because of high electricity consumption. To decrease the electrical power input requirements in electrolysis, our approach uses natural gas as an anode depolarizer. This approach essentially replaces one unit of electricity with one equivalent-energy unit of natural gas at much lower cost. The direct use of natural gas on the electrolyzer enables very high system efficiency with respect to primary energy. Experiments performed on single cells have shown a voltage reduction as much as 1 V when compared to conventional electrolyzers. System efficiency has been estimated to be 50 to 80%, depending on the electrolytic current. A 200-W prototype unit is being developed.
Pham, A Q
Experimental Study on Energy Efficiency of Heat-source Tower Heat Pump Units in Winter Condition
Building energy consumption in China has been increasing rapidly. And a small increase in the operation efficiency of the air-conditioning system can substantially decrease it. In this paper a new type heat pump is developed to improve the performance ... Keywords: Heat-source tower, Heat pump, Seasonal energy efficiency ratio(SEER), Hermal properties
Li Nianping; Zhang Wenjie; Wang Lijie; Liu Qiuke; Hu Jinhua
Ameren Illinois (Gas) - Cooking and Heating Business Efficiency Incentives
Ameren Illinois (Gas) - Cooking and Heating Business Efficiency Ameren Illinois (Gas) - Cooking and Heating Business Efficiency Incentives Ameren Illinois (Gas) - Cooking and Heating Business Efficiency Incentives < Back Eligibility Commercial Industrial Multi-Family Residential Nonprofit Savings Category Heating & Cooling Commercial Heating & Cooling Heating Home Weatherization Construction Commercial Weatherization Design & Remodeling Other Appliances & Electronics Water Heating Maximum Rebate General: $600,000 Program Info Expiration Date 05/31/2013 State Illinois Program Type Utility Rebate Program Rebate Amount Custom: $1.20/therm saved/yr Steamers: $300-$1200 Fryer: $400 Griddle: $50/ln. ft. Ovens: custom Storage Water Heaters: $150/unit Tankless Water Heater: $300/unit Gas Boiler/Furnace Replacement: $400 - $6,000
Advanced high efficiency concentrator cells
This report describes research to develop the technology needed to demonstrate a monolithic, multijunction, two-terminal, concentrator solar cell with a terrestrial power conversion efficiency greater than 35%. Under three previous subcontracts, Varian developed many of the aspects of a technology needed to fabricate very high efficiency concentrator cells. The current project was aimed at exploiting the new understanding of high efficiency solar cells. Key results covered in this report are as follows. (1) A 1.93-eV AlGaAs/1.42-eV GaAs metal-interconnected cascade cell was manufactured with a one-sun efficiency at 27.6% at air mass 1.5 (AM1.5) global. (2) A 1.0eV InGaAs cell was fabricated on the reverse'' side of a low-doped GaAs substrate with a one-sun efficiency of 2.5% AM1.5 diffuse and a short-circuit current of 14.4 mA/cm{sup 2}. (3) Small-scale manufacturing of GaAs p/n concentrator cells was attempted and obtained an excellent yield of high-efficiency cells. (4) Grown-in tunnel junction cell interconnects that are transparent and thermally stable using C and Si dopants were developed. 10 refs.
Gale, R. (Varian Associates, Inc., Palo Alto, CA (United States). Varian Research Center)
Efficient ion heating via finite-Larmor-radius ICRF
Ion heating by externally launched ion Bernstein waves is investigated in the ACT-1 hydrogen plasma. Detailed measurements of wave absorption and of the ion temperature profiles have clearly identified various heating layers near the ion cyclotron harmonics of deuterium-like and tritium-like ions. The observed heating of 10 eV/WATT/10/sup 10/ cm/sup -3/ and the power-balance estimates suggest excellent overall efficiency for FLR-ICRF heating.
Ono, M.; Wurden, G.A.; Wong, K.L.
Highly Efficient Modeling of Dynamic Coronal Loops
Observational and theoretical evidence suggests that coronal heating is impulsive and occurs on very small cross-field spatial scales. A single coronal loop could contain a hundred or more individual strands that are heated quasi-independently by nanoflares. It is therefore an enormous undertaking to model an entire active region or the global corona. Three-dimensional MHD codes have inadequate spatial resolution, and 1D hydro codes are too slow to simulate the many thousands of elemental strands that must be treated in a reasonable representation. Fortunately, thermal conduction and flows tend to smooth out plasma gradients along the magnetic field, so "0D models" are an acceptable alternative. We have developed a highly efficient model called Enthalpy-Based Thermal Evolution of Loops (EBTEL) that accurately describes the evolution of the average temperature, pressure, and density along a coronal strand. It improves significantly upon earlier models of this type--in accuracy, flexibility, and capability. It treats both slowly varying and highly impulsive coronal heating; it provides the differential emission measure distribution, DEM(T), at the transition region footpoints; and there are options for heat flux saturation and nonthermal electron beam heating. EBTEL gives excellent agreement with far more sophisticated 1D hydro simulations despite using four orders of magnitude less computing time. It promises to be a powerful new tool for solar and stellar studies.
J. A. Klimchuk; S. Patsourakos; P. J. Cargill
City of High Point Electric- Residential Energy Efficiency Rebate Program
The City of High Point offers the Hometown Green Program to help customers reduce energy use. Under this program, rebates are available for newly constructed energy efficient homes, heat pumps, and...
Evaluating High Efficiency Motor Retrofit
In the petrochemical and refining Industries, and most manufacturing plants, the reliable operation of AC motors always has been crucial to the continuous operation of the process. Now, the cost of operating these motors has also become a significant factor. Engineers Involved In motor specification can help lower plant operating costs and reduce electrical energy consumption dramatically by a relatively simple technique: retrofit of existing, standard-efficiency motors with new, high efficiency models. This article demonstrates strong reasons for motor retrofit, and explains step-by step how process and manufacturing engineering personnel can fully evaluate a retrofit decision.
Evans, T. A.
We are developing a novel high-efficiency, high-temperature steam electrolyzer. Although water or steam electrolysis is well known to be one of the cleanest ways to produce hydrogen, widespread utilization is hindered by high operational costs because of high electricity consumption. To decrease the electrical power input requirements in electrolysis, our approach uses natural gas as an anode depolarizer. This approach essentially replaces one unit of electricity with one equivalent-energy unit of natural gas at much lower cost. The direct use of natural gas on the electrolyzer enables very high system efficiency with respect to primary energy. Experiments performed on single cells have shown a voltage reduction as much as 1 V when compared to conventional electrolyzers. System efficiency has been estimated to be 50 to 80%, depending on the electrolytic current density. During FY02, we have accomplished several major milestones, including the development of a metal-to-ceramic seal that withstands 150 psi differential, the fabrication of the electrolyzer tubes of up to 16 inches in length, the improvement of single tube performance and the demonstration of the first electrolyzer stack.
Pham, A Q; See, E; Lenz, D; Martin, P; Glass, R
An Efficient Method for Online Calculations of Photolysis and Heating Rates
The authors present a computationally highly efficient method for the online calculation of photolysis and heating rates, which is especially suited for coupled transport�chemistry models. For this purpose, the spectral range 178.6 nm ? ? ? 752.5 ...
J. Landgraf; P. J. Crutzen
Oregon) Oregon) Northwest Energy Efficiency Alliance - Smart Water Heat Rebate Program (Oregon) < Back Eligibility Residential Savings Category Appliances & Electronics Water Heating Program Info Start Date 5/1/2012 State Oregon Program Type Non-Profit Rebate Program Provider Northwest Energy Efficiency Project The Northwest Energy Efficiency Alliance (NEEA) is offering a rebate program for homeowners who purchase and install an eligible heat pump water heater. A rebate of $750 is offered for qualifying heat pump water heater units. New units must replace an existing electric water heater and must be installed by a Smart Water Heat oriented contractor. New construction is also eligible for the rebate. All program requirements for equipment and installation must be met in order to receive rebates. Incentives are
Montana) Montana) Northwest Energy Efficiency Alliance - Smart Water Heat Rebate Program (Montana) < Back Eligibility Residential Savings Category Appliances & Electronics Water Heating Program Info Start Date 5/1/2012 State Montana Program Type Non-Profit Rebate Program Provider Northwest Energy Efficiency Project The Northwest Energy Efficiency Alliance (NEEA) is offering a rebate program for homeowners who purchase and install an eligible heat pump water heater. A rebate of $750 is offered for qualifying heat pump water heater units. New units must replace an existing electric water heater and must be installed by a Smart Water Heat oriented contractor. New construction is also eligible for the rebate. All program requirements for equipment and installation must be met in order to receive rebates. Incentives are
Condensing Heat Exchanger for Optimization of Energy Efficiency
Historically, boiler efficiency has been limited due to the minimum temperature allowed at the stack. Heat lost up the stack was in exchange for keeping the flue gas temperature above the water vapor dew point. If water vapor was allowed to condense out, rapid deterioration, due to acid corrosion, of the outlet duct and stack would result. With the development of the condensing heat exchanger, boiler efficiency can now exceed 90%. Approximately 1% gain in boiler efficiency can be expected for every 40F (4.5C) reduction in flue gas stack temperature. In the CHX� condensing heat exchanger, all gas wetted surfaces are covered with DuPont Teflon�. The Teflon covered heat exchanger surfaces are impervious to all acids normally resulting from the combustion of fossil fuels. This allows the flue gas to be cooled to below the water vapor dew point with no subsequent corrosion of the heat exchanger surfaces.
Carrigan, J. F.; Johnson, D. W.; DiVitto, J. G.; Schulze, K. H.
The Northwest Energy Efficiency Alliance (NEEA) is offering a rebate program for homeowners who purchase and install an eligible heat pump water heater. A rebate of 1,000 is...
Development of Technologies on Innovative-Simplified Nuclear Power Plant Using High-Efficiency Steam Injectors (12) Evaluations of Spatial Distributions of Flow and Heat Transfer in Steam Injector
Next-generation nuclear reactor systems have been under development aiming at simplified system and improvement of safety and credibility. One of the innovative technologies is the supersonic steam injector, which has been investigated as one of the most important component of the next-generation nuclear reactor. The steam injector has functions of a passive pump without large motor or turbo-machinery and a high efficiency heat exchanger. The performances of the supersonic steam injector as a pump and a heat exchanger are dependent on direct contact condensation phenomena between a supersonic steam and a sub-cooled water jet. In previous studies of the steam injector, there are studies about the operating characteristics of steam injector and about the direct contact condensation between static water pool and steam in atmosphere. However, there is a little study about the turbulent heat transfer and flow behavior under the great shear stress. In order to examine the heat transfer and flow behavior in supersonic steam injector, it is necessary to measure the spatial temperature distribution and velocity in detail. The present study, visible transparent supersonic steam injector is used to obtain the axial pressure distributions in the supersonic steam injector, as well as high speed visual observation of water jet and steam interface. The experiments are conducted with and without non-condensable gas. The experimental results of the interfacial flow behavior between steam and water jet are obtained. It is experimentally clarified that an entrainment exists on the water jet surface. It is also clarified that discharge pressure is depended on the steam supply pressure, the inlet water flow rate, the throat diameter and non-condensable flow rate. Finally a heat flux is estimated about 19 MW/m{sup 2} without non-condensable gas condition in steam. (authors)
Yutaka Abe; Yujiro Kawamoto [University of Tsukuba, Tsukuba, Ibaraki (Japan); Chikako Iwaki [Toshiba Corporation (Japan); Tadashi Narabayashi [Hokkaido University, Kita-ku, Sapporo (Japan); Michitsugu Mori; Shuichi Ohmori [Tokyo Electric Power Company (Japan)
Observational and theoretical evidence suggests that coronal heating is impulsive and occurs on very small cross-field spatial scales. A single coronal loop could contain a hundred or more individual strands that are heated quasi-independently by nanoflares. It is therefore an enormous undertaking to model an entire active region or the global corona. Three-dimensional MHD codes have inadequate spatial resolution, and 1D hydro codes are too slow to simulate the many thousands of elemental strands that must be treated in a reasonable representation. Fortunately, thermal conduction and flows tend to smooth out plasma gradients along the magnetic field, so "0D models" are an acceptable alternative. We have developed a highly efficient model called Enthalpy-Based Thermal Evolution of Loops (EBTEL) that accurately describes the evolution of the average temperature, pressure, and density along a coronal strand. It improves significantly upon earlier models of this type--in accuracy, flexibility, and capability. It ...
Klimchuk, J A; Cargill, P J
Candidate Alloys for Cost-Effective, High-Efficiency, High ...
the efficiency of heat exchange in these fuel cells require both development and careful ..... 3rd EPRI Conference on Advances in Materials Technology for Fossil.
Idaho) Idaho) Northwest Energy Efficiency Alliance - Smart Water Heat Rebate Program (Idaho) < Back Eligibility Residential Savings Category Appliances & Electronics Water Heating Program Info Start Date 05/01/2012 State Idaho Program Type Non-Profit Rebate Program The Northwest Energy Efficiency Alliance (NEEA) is offering a rebate program for homeowners who purchase and install an eligible heat pump water heater. A rebate of $750 is offered for qualifying heat pump water heater units. New units must replace an existing electric water heater and must be installed by a Smart Water Heat oriented contractor. New construction is also eligible for the rebate. All program requirements for equipment and installation must be met in order to receive rebates. Incentives are
Home Performance with Energy Star High Efficiency Measure Incentive (HEMI)
Home Performance with Energy Star High Efficiency Measure Incentive Home Performance with Energy Star High Efficiency Measure Incentive (HEMI) Home Performance with Energy Star High Efficiency Measure Incentive (HEMI) < Back Eligibility Residential Savings Category Heating & Cooling Commercial Heating & Cooling Heating Home Weatherization Commercial Weatherization Cooling Appliances & Electronics Sealing Your Home Ventilation Manufacturing Commercial Lighting Lighting Water Heating Maximum Rebate $3,000 Program Info State New York Program Type State Rebate Program Rebate Amount 10% of project costs Provider New York State Energy Research and Development Authority The New York State Research and Development Authority (NYSERDA) offers an incentive for homeowners of 1-4 homes that participate in the Home Performance with Energy Star program. The program entitles the participant
High-efficiency photoionization detector
A high efficiency photoionization detector using tetraaminoethylenes in a gaseous state having a low ionization potential and a relative photoionization cross section which closely matches the emission spectrum of xenon gas. Imaging proportional counters are also disclosed using the novel photoionization detector of the invention. The compound of greatest interest is TMAE which comprises tetrakis(dimethylamino)ethylene which has a measured ionization potential of 5.36 +- 0.02 eV, and a vapor pressure of 0.35 torr at 20/sup 0/C.
Modeling of Proposed Changes to SIUC Central Heating, Air-Conditioning, and Power Plant Incorporating Variable Frequency Drive (VFD) and High Efficiency Turbine.
??Currently, the Southern Illinois University Carbondale (SIUC) power plant produces steam at high pressure to drive a high pressure (HP) turbine to make a portion� (more)
Su, Heyin
Ceramic heat pipes for high temperature heat removal
Difficulties in finding metal or protected metal components that exhibit both strength and corrosion resistance at high temperature have severely restricted the application of effective heat recovery techniques to process heat furnaces. A potential method of overcoming this restriction is to use heat pipes fabricated from ceramic materials to construct counterflow recuperators. A development program has been initiated to demonstrate the technical and eventually the economical feasibility of ceramic heat pipes and ceramic heat pipe recuperators. The prime candidate for heat pipe construction is SiC. Closed-end tubes of this material have been prepared by chemical vapor deposition (CVD). These tubes were lined internally with tungsten by a subsequent CVD operation, partially filled with sodium, and sealed by brazing a tungsten lined SiC plug into the open-end with a palladium--cobalt alloy. Heat pipes constructed in this manner have been successfully operated in vacuum at temperatures of 1225/sup 0/K and in air at a temperature of 1125/sup 0/K. The heat source used initially for the air testing was an induction heated metallic sleeve in thermal contact with the test unit. Subsequent testing has shown that a silicon carbide heat pipe can be successfully operated with natural gas burners providing the input heat. Methods of fabricating and testing these devices are described.
Keddy, E.S.; Ranken, W.A.
High Efficiency Fans and High Efficiency Electrical Motors
Replacing nominal efficient electrical motors with premium efficiency can save on electrical power costs in cotton gins. Connected horsepower load on industrial air fans is approximately 60% of the total horsepower in a typical cotton gin. By replacing old inefficient centrifugal fans with new higher efficiency fans, additional power savings can be achieved.
Breedlove, C. W.
High-efficiency photovoltaic cells
High efficiency solar converters comprised of a two cell, non-lattice matched, monolithic stacked semiconductor configuration using optimum pairs of cells having bandgaps in the range 1.6 to 1.7 eV and 0.95 to 1.1 eV, and a method of fabrication thereof, are disclosed. The high band gap subcells are fabricated using metal organic chemical vapor deposition (MOCVD), liquid phase epitaxy (LPE) or molecular beam epitaxy (MBE) to produce the required AlGaAs layers of optimized composition, thickness and doping to produce high performance, heteroface homojunction devices. The low bandgap subcells are similarly fabricated from AlGa(As)Sb compositions by LPE, MBE or MOCVD. These subcells are then coupled to form a monolithic structure by an appropriate bonding technique which also forms the required transparent intercell ohmic contact (IOC) between the two subcells. Improved ohmic contacts to the high bandgap semiconductor structure can be formed by vacuum evaporating to suitable metal or semiconductor materials which react during laser annealing to form a low bandgap semiconductor which provides a low contact resistance structure.
Yang, H.T.; Zehr, S.W.
Energy Efficient Steam Trapping of Trace Heating Systems
Since as many as 40-60% of a plant's steam traps may be used on steam tracer lines, it is essential to select the correct, properly sized 'traps'; to optimize the efficient removal of condensate while providing maximum heat transfer to maintain desired product temperatures and greatly reduce steam losses. Factors related to achieving uniform product temperatures and maximum heat transfer rates and energy efficiency are: 1.Types and Methods used for Steam Tracing; 2. Systematic heat balance required to achieve economic tracer lengths; 3. Maximum allowable trapping distance for specific applications 4.Data important to determine condensate loads; 5. Trap selection, sizing, good installation practices, and proper maintenance. Using an engineered approach to steam trapping of trace heating systems have resulted in stable tracer line temperatures while reducing steam consumption 10-50% with minimum maintenance.
Krueger, R. G.; Wilt, G. W.
Commercial Air-Source Heat Pumps, Purchasing Specifications for Energy-Efficient Products (Fact Sheet)
Energy efficiency purchasing specifications for federal procurements of commercial air-source heat pumps.
Not Available
Coil said to up heat reclaimer efficiency 3-5%
The Elton Corp. will introduce a new heat reclaimer coil that can be used with its flue gas heat claimer to produce high-temperature hot water. The new coil, which can bring water from 125 to 165 degrees for users that require hotter water, can increase fuel savings by 3 to 5 percent over the standard unit. At prices starting at $32,000 to generate 20 gallons per minute, the heat reclaimer can pay for itself in as little as four months. Both the heat reclaimer and coil are custom built at Eldon's Louisiana plant.
Bringing Energy Efficiency to High Performance Computing
Bringing Energy Efficiency to High Performance Computing Oak Ridge National Laboratory's Jaguar Supercomputer William Tschudi September 2013 The ability of high performance...
Energy-Efficient Water Heating Program for the Residential Sector.
During the power surplus period of the late 1980's, Bonneville sponsored market research which provided an understanding of the market environment in the water heating end-use. The major areas of investigation included market trends, consumer purchasing practices, unit price, and availability of energy-efficient models. In 1988, Bonneville conducted a series of meetings with utilities operating water heater programs. Discussions focused on utility program concerns and the appropriate role for Bonneville as the region seeks efficiency in residential water heating. The design of the Program is based to a large degree on the experiences gained by regional utilities operating water heater incentive programs. In addition, an analysis of incentive programs operated outside the region has been helpful in the development of a regional program. Bonneville is a member of the Appliance Efficiency Group (AEG), formerly the Northwest Appliance Efficiency Group, and participates in discussions on water heating issues as they relate to the Pacific Northwest. The work done with the Appliance Efficiency Group has provided additional input in the development of the Program. This Program has been developed using a Public Involvement Process. A draft program strategy was made available to the public for comment during April 1990. The comments received were considered in the development of this document.
United States. Bonneville Power Administration.
Design of Bulk Nanocomposites as High Efficiency Thermoelectric Materials |
Office of Science (SC) Website
Design of Bulk Nanocomposites as High Design of Bulk Nanocomposites as High Efficiency Thermoelectric Materials Energy Frontier Research Centers (EFRCs) EFRCs Home Centers Research Science Highlights Highlight Archives News & Events Publications Contact BES Home 04.27.12 Design of Bulk Nanocomposites as High Efficiency Thermoelectric Materials Print Text Size: A A A RSS Feeds FeedbackShare Page Scientific Achievement A newly synthesized bulk thermoelectric material that contains nanocrystals with the same orientation and structure as the host material breaks thermoelectric efficiency records by blocking thermal, but not electrical, conductivity. Significance and Impact A new strategy to design inexpensive materials that more efficiently convert heat to electricity. Research Details Thermoelectric materials directly generate electrical power from heat, but
Investigation on a Microwave High-Temperature Air Heat Exchanger
In present paper, an energy efficient air heat exchanger, based on accumulation of the heat generated by microwave absorbing materials is presented according �...
Southwest Gas Corporation - Commercial High-Efficiency Equipment Rebate
Southwest Gas Corporation - Commercial High-Efficiency Equipment Southwest Gas Corporation - Commercial High-Efficiency Equipment Rebate Program Southwest Gas Corporation - Commercial High-Efficiency Equipment Rebate Program < Back Eligibility Commercial Industrial Savings Category Other Appliances & Electronics Commercial Weatherization Commercial Heating & Cooling Water Heating Maximum Rebate General: 50% of price Boiler Steam Trap: 25% of price Program Info State Arizona Program Type Utility Rebate Program Rebate Amount Modulating Burner Control: $10,000 Boiler O2 Trim Control Pad: $10,000 Boiler Steam Trap: $250 Non-condensing Boiler: $1/MBtuh Condensing Boiler: $1.25/MBtuh Storage Water Heater: 50% of cost, up to $1,100 Tankless Water Heater: 50% of cost, up to $450 Griddle: 50% of cost, up to $600 Fryer: 50% of cost, up to $1,350
High-Efficiency Neutron Detection and Spectroscopy
High-Efficiency Neutron Detection and Spectroscopy. ... such as searches for WIMP dark matter, neutrinoless double beta decay, and solar neutrinos. ...
High-Efficiency Neutron Detection and Spectroscopy ...
... are also working on a large volume detector to use in the underground environment where high efficiency is more important that energy resolution. ...
Theoretical Design of a Thermosyphon for Efficient Process Heat Removal from Next Generation Nuclear Plant (NGNP) for Production of Hydrogen
The work reported here is the preliminary analysis of two-phase Thermosyphon heat transfer performance with various alkali metals. Thermosyphon is a device for transporting heat from one point to another with quite extraordinary properties. Heat transport occurs via evaporation and condensation, and the heat transport fluid is re-circulated by gravitational force. With this mode of heat transfer, the thermosyphon has the capability to transport heat at high rates over appreciable distances, virtually isothermally and without any requirement for external pumping devices. For process heat, intermediate heat exchangers (IHX) are required to transfer heat from the NGNP to the hydrogen plant in the most efficient way possible. The production of power at higher efficiency using Brayton Cycle, and hydrogen production requires both heat at higher temperatures (up to 1000oC) and high effectiveness compact heat exchangers to transfer heat to either the power or process cycle. The purpose for selecting a compact heat exchanger is to maximize the heat transfer surface area per volume of heat exchanger; this has the benefit of reducing heat exchanger size and heat losses. The IHX design requirements are governed by the allowable temperature drop between the outlet of the NGNP (900oC, based on the current capabilities of NGNP), and the temperatures in the hydrogen production plant. Spiral Heat Exchangers (SHE�s) have superior heat transfer characteristics, and are less susceptible to fouling. Further, heat losses to surroundings are minimized because of its compact configuration. SHEs have never been examined for phase-change heat transfer applications. The research presented provides useful information for thermosyphon design and Spiral Heat Exchanger.
Piyush Sabharwall; Fred Gunnerson; Akira Tokuhiro; Vivek Utgiker; Kevan Weaver; Steven Sherman
Secondary Heat Exchanger Design and Comparison for Advanced High Temperature Reactor
The goals of next generation nuclear reactors, such as the high temperature gas-cooled reactor and advance high temperature reactor (AHTR), are to increase energy efficiency in the production of electricity and provide high temperature heat for industrial processes. The efficient transfer of energy for industrial applications depends on the ability to incorporate effective heat exchangers between the nuclear heat transport system and the industrial process heat transport system. The need for efficiency, compactness, and safety challenge the boundaries of existing heat exchanger technology, giving rise to the following study. Various studies have been performed in attempts to update the secondary heat exchanger that is downstream of the primary heat exchanger, mostly because its performance is strongly tied to the ability to employ more efficient conversion cycles, such as the Rankine super critical and subcritical cycles. This study considers two different types of heat exchangers�helical coiled heat exchanger and printed circuit heat exchanger�as possible options for the AHTR secondary heat exchangers with the following three different options: (1) A single heat exchanger transfers all the heat (3,400 MW(t)) from the intermediate heat transfer loop to the power conversion system or process plants; (2) Two heat exchangers share heat to transfer total heat of 3,400 MW(t) from the intermediate heat transfer loop to the power conversion system or process plants, each exchanger transfers 1,700 MW(t) with a parallel configuration; and (3) Three heat exchangers share heat to transfer total heat of 3,400 MW(t) from the intermediate heat transfer loop to the power conversion system or process plants. Each heat exchanger transfers 1,130 MW(t) with a parallel configuration. A preliminary cost comparison will be provided for all different cases along with challenges and recommendations.
Piyush Sabharwall; Ali Siahpush; Michael McKellar; Michael Patterson; Eung Soo Kim
Idaho Falls Power - Energy Efficient Heat Pump Loan Program | Department of
Idaho Falls Power - Energy Efficient Heat Pump Loan Program Idaho Falls Power - Energy Efficient Heat Pump Loan Program Idaho Falls Power - Energy Efficient Heat Pump Loan Program < Back Eligibility Commercial Industrial Institutional Nonprofit Residential Schools Savings Category Heating & Cooling Commercial Heating & Cooling Heat Pumps Maximum Rebate Heat Pumps: $7,500 Ductless Heat Pumps: $5,000 Program Info State Idaho Program Type Utility Loan Program Rebate Amount $500 - $7,500 Provider Idaho Falls Power Idaho Falls Power offers zero interest loans to all eligible customers for the purchase and installation of energy efficient heat pumps. The Heat Pump Program applies to heating or cooling in existing buildings. Ducted, ductless, and geothermal heat pumps are all eligible for this offer. The program will loan up to 100% of the actual cost of installing heat pumps
Effect of microfouling on heat-transfer efficiency
Field experiments, performed at Keahole Point, Hawaii and in the Gulf of Mexico, were designed to determine the relationship between decreased heat transfer efficiency and the accumulation of corrosion and/or biofouling films on heat exchanger surfaces. The sample tubes were maintained under conditions simulating those of an Ocean Thermal Energy Conversion (OTEC) system and data from the two sites have been compared. Seawater flowed through 2.54 (internal diameter) metal tubes at approximately 1.8m sec/sup -1/. Four types of tubes were used: 5052 Aluminum (A1), Grade 2 titanium (Ti), 90-10 copper-nickel (Cu-Ni) and Allegheny-Ludlum 6X stainless ssteel (SS). All surfaces were colonized by microorganisms, though colonization of the Cu-Ni surface was initially retarded. Total film weight was greatest for the Al and Cu-Ni surfaces which were characterized by corrosion as well as microbial fouling. The total organic carbon: total nitrogen ratios of the fouling films from Ti, Al, SS and Cu-Ni, 4.2, 4.0, 4.8 and 7.9 respectively, remained constant throughout the experiment. The degradation of heat transfer efficiency due to the formation of fouling layers on Ti and SS is neither linear nor a simple exponential function. A microfouling model is proposed for corrosion-resistant surfaces that is consistent with field observations.
Little, B.; Berger, L.R.
White LED with High Package Extraction Efficiency
The goal of this project is to develop a high efficiency phosphor converting (white) Light Emitting Diode (pcLED) 1-Watt package through an increase in package extraction efficiency. A transparent/translucent monolithic phosphor is proposed to replace the powdered phosphor to reduce the scattering caused by phosphor particles. Additionally, a multi-layer thin film selectively reflecting filter is proposed between blue LED die and phosphor layer to recover inward yellow emission. At the end of the project we expect to recycle approximately 50% of the unrecovered backward light in current package construction, and develop a pcLED device with 80 lm/W{sub e} using our technology improvements and commercially available chip/package source. The success of the project will benefit luminous efficacy of white LEDs by increasing package extraction efficiency. In most phosphor-converting white LEDs, the white color is obtained by combining a blue LED die (or chip) with a powdered phosphor layer. The phosphor partially absorbs the blue light from the LED die and converts it into a broad green-yellow emission. The mixture of the transmitted blue light and green-yellow light emerging gives white light. There are two major drawbacks for current pcLEDs in terms of package extraction efficiency. The first is light scattering caused by phosphor particles. When the blue photons from the chip strike the phosphor particles, some blue light will be scattered by phosphor particles. Converted yellow emission photons are also scattered. A portion of scattered light is in the backward direction toward the die. The amount of this backward light varies and depends in part on the particle size of phosphors. The other drawback is that yellow emission from phosphor powders is isotropic. Although some backward light can be recovered by the reflector in current LED packages, there is still a portion of backward light that will be absorbed inside the package and further converted to heat. Heat generated in the package may cause a deterioration of encapsulant materials, affecting the performance of both the LED die and phosphor, leading to a decrease in the luminous efficacy over lifetime. Recent studies from research groups at Rensselaer Polytechnic Institute found that, under the condition to obtain a white light, about 40% of the light is transmitted outward of the phosphor layer and 60% of the light is reflected inward.1,2 It is claimed that using scattered photon extraction (SPE) technique, luminous efficacy is increased by 60%. In this project, a transparent/translucent monolithic phosphor was used to replace the powdered phosphor layer. In the normal pcLED package, the powdered phosphor is mixed with silicone either to be deposited on the top of LED die forming a chip level conversion (CLC) white LED or to be casted in the package forming a volume conversion white LED. In the monolithic phosphors there are no phosphor powder/silicone interfaces so it can reduce the light scattering caused by phosphor particles. Additionally, a multi-layer thin film selectively reflecting filter is inserted in the white LED package between the blue LED die and phosphor layer. It will selectively transmit the blue light from the LED die and reflect the phosphor's yellow inward emission outward. The two technologies try to recover backward light to the outward direction in the pcLED package thereby improving the package extraction efficiency.
Yi Zheng; Matthew Stough
Efficient high density train operations
The present invention provides methods for preventing low train voltages and managing interference, thereby improving the efficiency, reliability, and passenger comfort associated with commuter trains. An algorithm implementing neural network technology is used to predict low voltages before they occur. Once voltages are predicted, then multiple trains can be controlled to prevent low voltage events. Further, algorithms for managing inference are presented in the present invention. Different types of interference problems are addressed in the present invention such as "Interference. During Acceleration", "Interference Near Station Stops", and "Interference During Delay Recovery." Managing such interference avoids unnecessary brake/acceleration cycles during acceleration, immediately before station stops, and after substantial delays. Algorithms are demonstrated to avoid oscillatory brake/acceleration cycles due to interference and to smooth the trajectories of closely following trains. This is achieved by maintaining sufficient following distances to avoid unnecessary braking/accelerating. These methods generate smooth train trajectories, making for a more comfortable ride, and improve train motor reliability by avoiding unnecessary mode-changes between propulsion and braking. These algorithms can also have a favorable impact on traction power system requirements and energy consumption.
Gordon, Susanna P. (Oakland, CA); Evans, John A. (Hayward, CA)
High Efficiency New Metallurgical Technology
Mar 4, 2013 ... The alumina leaching rate of calcium aluminate in residue is over 80%. .... Different types of plasma torches including a high power steam plasma torch ... for about 50% of the total NOX emissions in the iron and steel industry.
High efficiency carbonate fuel cell/turbine hybrid power cycle
The hybrid power cycle studies were conducted to identify a high efficiency, economically competitive system. A hybrid power cycle which generates power at an LHV efficiency > 70% was identified that includes an atmospheric pressure direct carbonate fuel cell, a gas turbine, and a steam cycle. In this cycle, natural gas fuel is mixed with recycled fuel cell anode exhaust, providing water for reforming fuel. The mixed gas then flows to a direct carbonate fuel cell which generates about 70% of the power. The portion of the anode exhaust which is not recycled is burned and heat transferred through a heat exchanger (HX) to the compressed air from a gas turbine. The heated compressed air is then heated further in the gas turbine burner and expands through the turbine generating 15% of the power. Half the exhaust from the turbine provides air for the anode exhaust burner. All of the turbine exhaust eventually flows through the fuel cell cathodes providing the O2 and CO2 needed in the electrochemical reaction. Exhaust from the cathodes flows to a steam system (heat recovery steam generator, staged steam turbine generating 15% of the cycle power). Simulation of a 200 MW plant with a hybrid power cycle had an LHV efficiency of 72.6%. Power output and efficiency are insensitive to ambient temperature, compared to a gas turbine combined cycle; NOx emissions are 75% lower. Estimated cost of electricity for 200 MW is 46 mills/kWh, which is competitive with combined cycle where fuel cost is > $5.8/MMBTU. Key requirement is HX; in the 200 MW plant studies, a HX operating at 1094 C using high temperature HX technology currently under development by METC for coal gassifiers was assumed. A study of a near term (20 MW) high efficiency direct carbonate fuel cell/turbine hybrid power cycle has also been completed.
Steinfeld, G.; Maru, H.C. [Energy Research Corp., Danbury, CT (United States); Sanderson, R.A. [Sanderson (Robert) and Associates, Wethersfield, CT (United States)
High pressure ceramic heat exchanger
Many recuperators have components which react to corrosive gases and are used in applications where the donor fluid includes highly corrosive gases. These recuperators have suffered reduced life, increased service or maintenance, and resulted in increased cost. The present header assembly when used with recuperators reduces the brittle effect of a portion of the ceramic components. Thus, the present header assembly used with the present recuperator increases the life, reduces the service and maintenance, and reduces the increased cost associated with corrosive action of components used to manufacture recuperators. The present header assembly is comprised of a first ceramic member, a second ceramic member, a strengthening reinforcing member being in spaced relationship to the first ceramic member and the second ceramic member. The header assembly is further comprised of a refractory material disposed in contacting relationship with the first ceramic member, the second ceramic member and the strengthening reinforcing member. The present header assembly provides a high strength load bearing header assembly having good thermal cycling characteristics, good resistance to a corrosive environment and good steady state strength at elevated temperatures. 5 figs.
Harkins, B.D.; Ward, M.E.
Many recuperators have components which react to corrosive gases and are used in applications where the donor fluid includes highly corrosive gases. These recuperators have suffered reduced life, increased service or maintenance, and resulted in increased cost. The present header assembly when used with recuperators reduces the brittle effect of a portion of the ceramic components. Thus, the present header assembly used with the present recuperator increases the life, reduces the service and maintenance, and reduces the increased cost associated with corrosive action of components used to manufacture recuperators. The present header assembly is comprised of a first ceramic member, a second ceramic member, a strengthening reinforcing member being in spaced relationship to the first ceramic member and the second ceramic member. The header assembly is further comprised of a refractory material disposed in contacting relationship with the first ceramic member, the second ceramic member and the strengthening reinforcing member. The present header assembly provides a high strength load bearing header assembly having good thermal cycling characteristics, good resistance to a corrosive environment and good steady state strength at elevated temperatures.
Harkins, Bruce D. (San Diego, CA); Ward, Michael E. (Poway, CA)
Many recuperators have components which react to corrosive gases and are used in applications where the donor fluid includes highly corrosive gases. These recuperators have suffered reduced life, increased service or maintenance, and resulted in increased cost. The present header assembly when used with recuperators reduces the brittle effect of a portion of the ceramic components. Thus, the present header assembly used with the present recuperator increases the life, reduces the service and maintenance, and reduces the increased cost associated with corrosive action of components used to manufacture recuperators. The present header assembly is comprised of a first ceramic member, a second ceramic member, a reinforcing member being in spaced relationship to the first ceramic member and the second ceramic member. The header assembly is further comprised of a refractory material disposed in contacting relationship with the first ceramic member, the second ceramic member and the reinforcing member and having a strengthening member wrapped around the refractory material. The present header assembly provides a high strength load bearing header assembly having good thermal cycling characteristics, good resistance to a corrosive environment and good steady state strength at elevated temperatures.
Ohmically heated high-density Z pinch
The gross properties of a high-density (n approximately equal to 10$sup 27$ m$sup -3$), small-radius, (r = 10$sup -4$ m) gas-imbedded Z pinch have been examined considering only classical processes. The rate equation using only ohmic heating along with bremsstrahlung and radial heat transport shows that ohmic heating will rapidly take the pinch to thermonuclear temperatures for currents, I, greater than 1 MA. The radial heat loss for the pinch is very small for I greater than 1.5 MA. This suggests that the pinch could tolerate being driven to a nearby wall by an m = 1 kink. The laser technology for initiation of the small-diameter filament and the high-voltage technology for giving a 30-ns rise to a MA or more are available now. Some reactor considerations have been included. (auth)
Hammel, J.E.
Ultra-Compact High-Efficiency Luminaire for General Illumination
Cree has developed a new ultra-compact light emitting diode (LED) luminaire capable of providing high efficacy with excellent color quality that can lead to significant energy savings in today�??s commercial and retail applications. This success was based on an integrated development effort tailoring the LED component characteristics, optics, thermal management and driver design for the small footprint to achieve an overall system efficiency of �?� 70%. A new LED component was designed to provide high brightness and efficacy in a form factor that allowed for a small directional beam with a luminaire housing design able to dissipate the heat effectively using a small physical envelope. A very compact, 90% efficient driver was developed to meet the system performance while not taking away any thermal mass from the heat sink. A 91% efficient secondary optics was designed to maximize efficiency while providing a smooth beam. The reliability of the new LED component was robust under accelerated testing conditions. Luminaires were assembled integrating the novel LED component, secondary optics, heat sink and driver technology to demonstrate the system improvement. Cree has successfully completed this project by developing an ultra-compact LED luminaire that provided 380 lumens at a correlated color temperature (CCT) of 2822 K and color rendering index (CRI) of 94 with an efficacy of 94 lumens per watt (LPW) when operating at 4 W input power (steady state) with an overall system efficiency of 81%. At a higher input power of 9 Watts, the lamp provided 658 lumens at 71 LPW.
Ted Lowes
NREL Documents Efficiency of Mini-Split Heat Pumps (Fact Sheet)
A new report delivers mini-split heat pump (MSHP) performance data for use in whole-building simulation tools. Mini-split heat pumps (MSHPs) are highly efficient refrigerant-based air conditioning and heating systems that permit room-by-room conditioning and control in homes. Because of their size, efficiency, and price, MSHPs are very popular overseas and are gaining market share in energy-efficient home upgrades in the United States. They are a good option for retrofitting older homes that lack ductwork. To evaluate MSHP cost effectiveness and performance in U.S. homes, National Renewable Energy Laboratory (NREL) researchers are studying these systems in the laboratory, simulated buildings, and field test settings. A new NREL report describes an innovative laboratory approach to testing MSHPs and includes experimental performance maps for use in whole-building simulation tools. Most public information on MSHP performance is provided by equipment manufacturers, and is typically limited to performance at a single operating speed for heating and cooling. Mini-split heat pumps use variable speed components that spin up and down to continuously meet the heating or cooling need, significantly improving a system's operating efficiency. Measuring that efficiency in a laboratory is challenging and required new approaches to performance testing. NREL researchers worked with colleagues at Purdue University's Herrick Labs and Ecotope, Inc. to refine and apply this new approach to a suite of MSHP products. Researchers measured the performance of two MSHPs across a variety of operating conditions, which allowed, for the first time, development of accurate building simulation MSHP models. In the laboratory tests, researchers found that both MSHPs achieved manufacturer-reported performance at rating conditions. However, at other temperature and humidity conditions, the heat pumps capacity ranged from 40% above to 54% below the manufacturer-reported values. Knowing how performance varies is critical in order to reasonably estimate annual energy consumption of a MSHP, and to compare MSHPs to other heating and cooling options. Mini-split heat pump efficiency (COP) was seen to significantly exceed rated efficiency at low compressor speeds-a very important effect.
Multicolor, High Efficiency, Nanotextured LEDs
We report on research results in this project which synergize advanced material science approaches with fundamental optical physics concepts pertaining to light-matter interaction, with the goal of solving seminal problems for the development of very high performance light emitting diodes (LEDs) in the blue and green for Solid State Lighting applications. Accomplishments in the duration of the contract period include (i) heteroepitaxy of nitrogen-polar LEDs on sapphire, (ii) heteroepitaxy of semipolar (11{bar 2}2) green LEDs on sapphire, (iii) synthesis of quantum-dot loaded nanoporous GaN that emits white light without phosphor conversion, (iv) demonstration of the highest quality semipolar (11{bar 2}2) GaN on sapphire using orientation-controlled epitaxy, (v) synthesis of nanoscale GaN and InGaN medium, and (vi) development of a novel liftoff process for manufacturing GaN thin-film vertical LEDs. The body of results is presented in this report shows how a solid foundation has been laid, with several noticeable accomplishments, for innovative research, consistent with the stated milestones.
Jung Han; Arto Nurmikko
Conversion Tower for Dispatchable Solar Power: High-Efficiency Solar-Electric Conversion Power Tower
HEATS Project: Abengoa Solar is developing a high-efficiency solar-electric conversion tower to enable low-cost, fully dispatchable solar energy generation. Abengoa�s conversion tower utilizes new system architecture and a two-phase thermal energy storage media with an efficient supercritical carbon dioxide (CO2) power cycle. The company is using a high-temperature heat-transfer fluid with a phase change in between its hot and cold operating temperature. The fluid serves as a heat storage material and is cheaper and more efficient than conventional heat-storage materials, like molten salt. It also allows the use of a high heat flux solar receiver, advanced high thermal energy density storage, and more efficient power cycles.
A high-efficiency thermoelectric converter for space applications
This paper presents a concept for using high-temperature superconducting materials in thermoelectric generators (SCTE) to produce electricity at conversion efficiencies approaching 50% of the Carrot efficiency. The SCTE generator is applicable to systems operating in temperature ranges of high-temperature superconducting materials and thus would be a low-grade converter. Operating in cryogenic temperature ranges provides the advantage of inherently increasing the limits of the Carrot efficiency. Potential applications are for systems operating in space where the ambient temperatures are in the cryogenic temperature range. The advantage of using high-temperature superconducting material in a thermoelectric converter is that it would significantly reduce or eliminate the Joule heating losses in a thermoelectric element. This paper investigates the system aspects and the material requirements of the SCTE converter concept, and presents a conceptual design and an application for a space power system.
Metzger, J.D. [Westinghouse Savannah River Co., Aiken, SC (United States); El-Genk, M.S. [New Mexico Univ., Albuquerque, NM (United States). Inst. for Space Nuclear Power Studies
Metzger, J.D. (Westinghouse Savannah River Co., Aiken, SC (United States)); El-Genk, M.S. (New Mexico Univ., Albuquerque, NM (United States). Inst. for Space Nuclear Power Studies)
An Analysis of Efficiency Improvements in Residential Sized Heat Pumps, Final Report, May 1986
O'Neal, D. L.; Murphy, W. E.
Fusion blanket high-temperature heat transfer
Deep penetration of 14 MeV neutrons makes two-temperature region blankets feasible. A relatively low-temperature (approx. 300/sup 0/C) metallic structure is the vacuum/coolant pressure boundary, while the interior of the blanket, which is a simple packed bed of nonstructural material, operates at very high temperatures (>1000/sup 0/C). The water-cooled shell structure is thermally insulated from the steam-cooled interior. High-temperature steam can dramatically increase the efficiency of electric power generation, as well as produce hydrogen and oxygen-based synthetic fuels at high-efficiency.
Fillo, J.A.
USING LIGA BASED MICROFABRICATION TO IMPROVE OVERALL HEAT TRANSFER EFFICIENCY OF PRESSURIZED WATER REACTOR: I. Effects of Different Micro Pattern on Overall Heat Transfer.
The Pressurized Water Reactors (PWRs in Figure 1) were originally developed for naval propulsion purposes, and then adapted to land-based applications. It has three parts: the reactor coolant system, the steam generator and the condenser. The Steam generator (a yellow area in Figure 1) is a shell and tube heat exchanger with high-pressure primary water passing through the tube side and lower pressure secondary feed water as well as steam passing through the shell side. Therefore, a key issue in increasing the efficiency of heat exchanger is to improve the design of steam generator, which is directly translated into economic benefits. The past research works show that the presence of a pin-fin array in a channel enhances the heat transfer significantly. Hence, using microfabrication techniques, such as LIGA, micro-molding or electroplating, some special microstructures can be fabricated around the tubes in the heat exchanger to increase the heat-exchanging efficiency and reduce the overall size of the heat-exchanger for the given heat transfer rates. In this paper, micro-pin fins of different densities made of SU-8 photoresist are fabricated and studied to evaluate overall heat transfer efficiency. The results show that there is an optimized micro pin-fin configuration that has the best overall heat transfer effects.
Zhang, M.; Ibekwe, S.; Li, G.; Pang, S.S.; and Lian, K.
Energy Efficient Process Heating: Insulation and Thermal Mass Kevin Carpenter and Kelly Kissock
1 Energy Efficient Process Heating: Insulation and Thermal Mass Kevin Carpenter and Kelly Kissock tanks and reducing thermal mass. A companion paper, Energy Efficiency Process Heating: Managing Air Flow of the oven/furnace. Reducing the quantity of energy lost to thermal mass in a process heating system saves
Kissock, Kelly
Energy Efficiency Improvements Through the Use of Combined Heat...
Use of Combined Heat and Power (CHP) in Buildings Combined technology helps Federal energy managers meet mission critical energy needs Buildings Cooling, Heating and Power...
Heat Treatment of High Pressure Die Castings; Challenges and ...
High Strength Aluminum Brazing Sheets for Condenser Fins of Automotive Heat Exchangers � High Temperature Creep Characterization of A380 Cast�...
Influence of Transfer Efficiency of the Outdoor Pipe Network and Boiler Operating Efficiency on the Building Heat Consumption Index
This paper analyzes the influence of transfer efficiency of the outdoor pipe network and operating efficiency of the boiler on the building heat consumption index, on the premise of saving up to 65 percent energy in different climates. The results show that transfer efficiency is not influenced by the climate, and the influence is in accordance with that in other climates. The article also presents data on the energy consumption caused by the improvement of the transfer efficiency of the outdoor pipe network and the operating efficiency of the boiler, and the calculated formula for the building heat consumption index on the condition of saving 65 percent energy.
Fang, X.; Wang, Z.; Liu, H.
Measure Guideline: High Efficiency Natural Gas Furnaces
This Measure Guideline covers installation of high-efficiency gas furnaces. Topics covered include when to install a high-efficiency gas furnace as a retrofit measure, how to identify and address risks, and the steps to be used in the selection and installation process. The guideline is written for Building America practitioners and HVAC contractors and installers. It includes a compilation of information provided by manufacturers, researchers, and the Department of Energy as well as recent research results from the Partnership for Advanced Residential Retrofit (PARR) Building America team.
Brand, L.; Rose, W.
Implications of high efficiency power cycles for fusion reactor design
The implications of the High Efficiency Power Cycle for fusion reactors are examined. The proposed cycle converts most all of the high grade CTR heat input to electricity. A low grade thermal input (T approximately 100$sup 0$C) is also required, and this can be supplied at low cost geothermal energy at many locations in the U. S. Approximately 3 KW of low grade heat is required per KW of electrical output. The thermodynamics and process features of the proposed cycle are discussed. Its advantages for CTR's are that low Q machines (e.g. driven Tokamaks, mirrors) can operate with a high (approximately 80 percent) conversion of CTR fusion energy to electricity, where with conventional power cycles no plant output could be achieved with such low Q operation. (auth)
Powell, J.R.; Usher, J.; Salzano, F.J.
Highly efficient 6-stroke engine cycle with water injection
combustion piston engine. The increased efficiency is a result of recovering heat primarily from the engine exhaust gases, and also from the engine coolant.
Purchasing a New Energy-Efficient Central Heating System | Department of
Purchasing a New Energy-Efficient Central Heating System Purchasing a New Energy-Efficient Central Heating System Purchasing a New Energy-Efficient Central Heating System October 21, 2008 - 4:00am Addthis John Lippert Energy prices are skyrocketing. According to the Energy Information Administration's October 7, 2008 forecast, heating fuel expenditures for the average household using oil as its primary heating fuel are expected to increase by $449 over last winter. Households using natural gas to heat their homes can expect to pay $155 more this winter, on average, than last year, and those using propane can expect to pay $188 more. Households heating primarily with electricity can expect to pay an average of $89 more. That's a lot of money resulting solely from rising heating expenses. You may long for the "good old days," but when it comes to heating systems,
High heating oil prices discourage heating oil supply contracts ...
U.S. Energy Information Administration (EIA)
EIA's Short-Term Energy and Winter Fuels Outlook expects the U.S. home heating oil price will average $3.71 per gallon for the season, ...
Experimental Investigation of Bendable Heat Pipes.
??Heat pipes are highly conductive heat transfer devices. They use the latent heat of the working fluid for efficient heat transfer over a very small� (more)
High Efficiency Solar Integrated Roof Membrane Product
This project was designed to address the Solar Energy Technology Program objective, to develop new methods to integrate photovoltaic (PV) cells or modules within a building-integrated photovoltaic (BIPV) application that will result in lower installed cost as well as higher efficiencies of the encapsulated/embedded PV module. The technology assessment and development focused on the evaluation and identification of manufacturing technologies and equipment capable of producing such low-cost, high-efficiency, flexible BIPV solar cells on single-ply roofing membranes.
Partyka, Eric; Shenoy, Anil
Estimating Costs and Efficiency of Storage, Demand, and Heat...
more efficient system. When considering a water heater model for your home, estimate its energy efficiency and annual operating cost. Then, compare costs with other more andor...
High-efficiency silicon concentrator cell commercialization
This report summarizes the first phase of a forty-one month program to develop a commercial, high-efficiency concentrator solar cell and facility for manufacturing it. The period covered is November 1, 1990 to December 31, 1991. This is a joint program between the Electric Power Research Institute (EPRI) and Sandia National Laboratories. (This report is also published by EPRI as EPRI report number TR-102035.) During the first year of the program, SunPower accomplished the following major objectives: (1) a new solar cell fabrication facility, which is called the Cell Pilot Line (CPL), (2) a baseline concentrator cell process has been developed, and (3) a cell testing facility has been completed. Initial cell efficiencies are about 23% for the baseline process. The long-range goal is to improve this efficiency to 27%.
Sinton, R.A.; Swanson, R.M. [SunPower Corp., Sunnyvale, CA (US)
Building Technologies Office: Highly Energy Efficient Wall Systems...
Highly Energy Efficient Wall Systems Research Project to someone by E-mail Share Building Technologies Office: Highly Energy Efficient Wall Systems Research Project on Facebook...
Energy Efficiency Opportunities in Federal High Performance Computing...
Energy Efficiency Opportunities in Federal High Performance Computing Data Centers Energy Efficiency Opportunities in Federal High Performance Computing Data Centers Case study...
Vehicle Technologies Office: Materials for High Efficiency Combustion...
High Efficiency Combustion Engines to someone by E-mail Share Vehicle Technologies Office: Materials for High Efficiency Combustion Engines on Facebook Tweet about Vehicle...
Modelling and fabrication of high-efficiency silicon solar cells
This report covers the research conducted on modelling and development of high-efficiency silicon solar cells during the period May 1989 to August 1990. First, considerable effort was devoted toward developing a ray-tracing program for the photovoltaic community to quantify and optimize surface texturing for solar cells. Second, attempts were made to develop a hydrodynamic model for device simulation. Such a model is somewhat slower than drift-diffusion type models like PC-1D, but it can account for more physical phenomena in the device, such as hot carrier effects, temperature gradients, thermal diffusion, and lattice heat flow. In addition, Fermi-Dirac statistics have been incorporated into the model to deal with heavy doping effects more accurately. Third and final component of the research includes development of silicon cell fabrication capabilities and fabrication of high-efficiency silicon cells. 84 refs., 46 figs., 10 tabs.
Rohatgi, A.; Smith, A.W.; Salami, J. [Georgia Inst. of Tech., Atlanta, GA (United States). School of Electrical Engineering] [Georgia Inst. of Tech., Atlanta, GA (United States). School of Electrical Engineering
High temperature heat pipes for waste heat recovery
Operation of heat pipes in air at temperatures above 1200/sup 0/K has been accomplished using SiC as a shell material and a chemical vapor deposit (CVD) tungsten inner liner for protection of the ceramic from the sodium working fluid. The CVD tungsten has been used as a distribution wick for the gravity assisted heat pipe through the development of a columnar tungsten surface structure, achieved by control of the metal vapor deposition rate. Wick performance has been demonstrated in tests at approximately 2 kW throughput with a 19-mm-i.d. SiC heat pipe. Operation of ceramic heat pipes in repeated start cycle tests has demonstrated their ability to withstand temperature rise rates of greater than 1.2 K/s.
Merrigan, M.A.; Keddy, E.S.
Magnetic Refrigeration Technology for High Efficiency Air Conditioning
Magnetic refrigeration was investigated as an efficient, environmentally friendly, flexible alternative to conventional residential vapor compression central air conditioning systems. Finite element analysis (FEA) models of advanced geometry active magnetic regenerator (AMR) beds were developed to minimize bed size and thus magnet mass by optimizing geometry for fluid flow and heat transfer and other losses. Conventional and magnetocaloric material (MCM) regenerator fabrication and assembly techniques were developed and advanced geometry passive regenerators were built and tested. A subscale engineering prototype (SEP) magnetic air conditioner was designed, constructed and tested. A model of the AMR cycle, combined with knowledge from passive regenerator experiments and FEA results, was used to design the regenerator beds. A 1.5 Tesla permanent magnet assembly was designed using FEA and the bed structure and plenum design was extensively optimized using FEA. The SEP is a flexible magnetic refrigeration platform, with individually instrumented beds and high flow rate and high frequency capability, although the current advanced regenerator geometry beds do not meet performance expectations, probably due to manufacturing and assembly tolerances. A model of the AMR cycle was used to optimize the design of a 3 ton capacity magnetic air conditioner, and the system design was iterated to minimize external parasitic losses such as heat exchanger pressure drop and fan power. The manufacturing cost for the entire air conditioning system was estimated, and while the estimated SEER efficiency is high, the magnetic air conditioning system is not cost competitive as currently configured. The 3 ton study results indicate that there are other applications where magnetic refrigeration is anticipated to have cost advantages over conventional systems, especially applications where magnetic refrigeration, through the use of its aqueous heat transfer fluid, could eliminate intermediate heat exchangers or oil distribution issues found in traditional vapor compression systems.
Boeder, A; Zimm, C
Waste Heat Utilization to Increase Energy Efficiency in the Metals ...
This system will produce electricity, and/or process steam. � Low grade: ... or Save Conflict]. Waste Heat Reduction and Recovery Options for Metals Industry.
NEI Corporation Technology Promotes Efficiency in Heat Exchangers...
Top image: Filmwise condensation (FWC), Bottom image: Dropwise condensation (DWC) R&D Opportunity In electrical utilities and in many process industries, improved heat...
High efficiency inverter and ballast circuits
A high efficiency push-pull inverter circuit employing a pair of relatively high power switching transistors is described. The switching on and off of the transistors is precisely controlled to minimize power losses due to common-mode conduction or due to transient conditions that occur in the process of turning a transistor on or off. Two current feed-back transformers are employed in the transistor base drives; one being saturable for providing a positive feedback, and the other being non-saturable for providing a subtractive feedback.
Nilssen, O.K.
Design details of a compact heat exchanger and supporting hardware for heat recuperation in a high-temperature electrolysis application are presented. The recuperative heat exchanger uses a vacuum-brazed plate-fin design and operates between 300 and 800�C. It includes corrugated inserts for enhancement of heat transfer coefficients and extended heat transfer surface area. Two recuperative heat exchangers are required per each four-stack electrolysis module. The heat exchangers are mated to a base manifold unit that distributes the inlet and outlet flows to and from the four electrolysis stacks. Results of heat exchanger design calculations and assembly details are also presented.
G. K. Housley; J.E. O'Brien; G.L. Hawkes
North American Overview - Heat Pumps Role in Buildings Energy Efficiency Improvement
A brief overview of the situation in North America regarding buildings energy use and the current and projected heat pump market is presented. R&D and deployment strategies for heat pumps, and the impacts of the housing market and efficiency regulations on the heating and cooling equipment market are summarized as well.
Baxter, Van D [ORNL; Bouza, Antonio [U.S. Department of Energy; Gigu�re, Daniel [Natural Resources Canada; Hosatte, Sophie [Natural Resources Canada
OAK B202 HIGH EFFICIENCY GENERATION OF HYDROGEN FUELS USING NUCLEAR POWER. Combustion of fossil fuels, used to power transportation, generate electricity, heat homes and fuel industry provides 86% of the world's energy. Drawbacks to fossil fuel utilization include limited supply, pollution, and carbon dioxide emissions. Carbon dioxide emissions, thought to be responsible for global warming, are now the subject of international treaties. Together, these drawbacks argue for the replacement of fossil fuels with a less-polluting potentially renewable primary energy such as nuclear energy. Conventional nuclear plants readily generate electric power but fossil fuels are firmly entrenched in the transportation sector. Hydrogen is an environmentally attractive transportation fuel that has the potential to displace fossil fuels. Hydrogen will be particularly advantageous when coupled with fuel cells. Fuel cells have higher efficiency than conventional battery/internal combustion engine combinations and do not produce nitrogen oxides during low-temperature operation. Contemporary hydrogen production is primarily based on fossil fuels and most specifically on natural gas. When hydrogen is produced using energy derived from fossil fuels, there is little or no environmental advantage. There is currently no large scale, cost-effective, environmentally attractive hydrogen production process available for commercialization, nor has such a process been identified. The objective of this work is to find an economically feasible process for the production of hydrogen, by nuclear means, using an advanced high-temperature nuclear reactor as the primary energy source. Hydrogen production by thermochemical water-splitting (Appendix A), a chemical process that accomplishes the decomposition of water into hydrogen and oxygen using only heat or, in the case of a hybrid thermochemical process, by a combination of heat and electrolysis, could meet these goals. Hydrogen produced from fossil fuels has trace contaminants (primarily carbon monoxide) that are detrimental to precious metal catalyzed fuel cells, as is now recognized by many of the world's largest automobile companies. Thermochemical hydrogen will not contain carbon monoxide as an impurity at any level. Electrolysis, the alternative process for producing hydrogen using nuclear energy, suffers from thermodynamic inefficiencies in both the production of electricity and in electrolytic parts of the process. The efficiency of electrolysis (electricity to hydrogen) is currently about 80%. Electric power generation efficiency would have to exceed 65% (thermal to electrical) for the combined efficiency to exceed the 52% (thermal to hydrogen) calculated for one thermochemical cycle. Thermochemical water-splitting cycles have been studied, at various levels of effort, for the past 35 years. They were extensively studied in the late 70s and early 80s but have received little attention in the past 10 years, particularly in the U.S. While there is no question about the technical feasibility and the potential for high efficiency, cycles with proven low cost and high efficiency have yet to be developed commercially. Over 100 cycles have been proposed, but substantial research has been executed on only a few. This report describes work accomplished during a three-year project whose objective is to ''define an economically feasible concept for production of hydrogen, by nuclear means, using an advanced high temperature nuclear reactor as the energy source.'' The emphasis of the first phase was to evaluate thermochemical processes which offer the potential for efficient, cost-effective, large-scale production of hydrogen from water in which the primary energy input is high temperature heat from an advanced nuclear reactor and to select one (or, at most three) for further detailed consideration. During Phase 1, an exhaustive literature search was performed to locate all cycles previously proposed. The cycles located were screened using objective criteria to determine which could benefit, in terms of efficien
OAK B202 HIGH EFFICIENCY GENERATION OF HYDROGEN FUELS USING NUCLEAR POWER. Combustion of fossil fuels, used to power transportation, generate electricity, heat homes and fuel industry provides 86% of the world's energy. Drawbacks to fossil fuel utilization include limited supply, pollution, and carbon dioxide emissions. Carbon dioxide emissions, thought to be responsible for global warming, are now the subject of international treaties. Together, these drawbacks argue for the replacement of fossil fuels with a less-polluting potentially renewable primary energy such as nuclear energy. Conventional nuclear plants readily generate electric power but fossil fuels are firmly entrenched in the transportation sector. Hydrogen is an environmentally attractive transportation fuel that has the potential to displace fossil fuels. Hydrogen will be particularly advantageous when coupled with fuel cells. Fuel cells have higher efficiency than conventional battery/internal combustion engine combinations and do not produce nitrogen oxides during low-temperature operation. Contemporary hydrogen production is primarily based on fossil fuels and most specifically on natural gas. When hydrogen is produced using energy derived from fossil fuels, there is little or no environmental advantage. There is currently no large scale, cost-effective, environmentally attractive hydrogen production process available for commercialization, nor has such a process been identified. The objective of this work is to find an economically feasible process for the production of hydrogen, by nuclear means, using an advanced high-temperature nuclear reactor as the primary energy source. Hydrogen production by thermochemical water-splitting (Appendix A), a chemical process that accomplishes the decomposition of water into hydrogen and oxygen using only heat or, in the case of a hybrid thermochemical process, by a combination of heat and electrolysis, could meet these goals. Hydrogen produced from fossil fuels has trace contaminants (primarily carbon monoxide) that are detrimental to precious metal catalyzed fuel cells, as is now recognized by many of the world's largest automobile companies. Thermochemical hydrogen will not contain carbon monoxide as an impurity at any level. Electrolysis, the alternative process for producing hydrogen using nuclear energy, suffers from thermodynamic inefficiencies in both the production of electricity and in electrolytic parts of the process. The efficiency of electrolysis (electricity to hydrogen) is currently about 80%. Electric power generation efficiency would have to exceed 65% (thermal to electrical) for the combined efficiency to exceed the 52% (thermal to hydrogen) calculated for one thermochemical cycle. Thermochemical water-splitting cycles have been studied, at various levels of effort, for the past 35 years. They were extensively studied in the late 70s and early 80s but have received little attention in the past 10 years, particularly in the U.S. While there is no question about the technical feasibility and the potential for high efficiency, cycles with proven low cost and high efficiency have yet to be developed commercially. Over 100 cycles have been proposed, but substantial research has been executed on only a few. This report describes work accomplished during a three-year project whose objective is to ''define an economically feasible concept for production of hydrogen, by nuclear means, using an advanced high temperature nuclear reactor as the energy source.'' The emphasis of the first phase was to evaluate thermochemical processes which offer the potential for efficient, cost-effective, large-scale production of hydrogen from water in which the primary energy input is high temperature heat from an advanced nuclear reactor and to select one (or, at most three) for further detailed consideration. During Phase 1, an exhaustive literature search was performed to locate all cycles previously proposed. The cycles located were screened using objective criteria to determine which could
High Heating Rate Thermal Desorption for Molecular Surface ...
High Heating Rate Thermal Desorption for Molecular Surface Sampling Note: The technology described above is an early stage opportunity. Licensing ...
Multi-band high efficiency power amplifier
Baseline) Output Power (Transformer) Drain Efficiency (Performance Frequency (GHz) Output Power (Transformer) DrainEfficiency (Transformer) Output Power (Baseline) Drain
Besprozvanny, Randy-Alexander Randolph
Energy Efficiency Supporting Policy and Heat Pumping Technology in Japan
(U.S. dollars) is calculated with Japan = 1. #12;2-1. Eco Cute : example of countermeasure for energy feature Counter flow Heat exchanger Heat pump unit Storage tank Ref: TEPCO Website Ref: HPTCJ HP Space in Residential sector (FY2009) e.g. Gas stove e.g. Air- conditioner e.g. Domestic water heater e.g. lighting PC
Oak Ridge National Laboratory
Field Measurements of Heating Efficiency of Electric Forced-Air Furnaces in Six Manufactured Homes.
This report presents the results of field measurements of heating efficiency for six manufactured homes in the Pacific Northwest heated with electric forced-air systems. This is the first in a series of regional and national efforts to measure in detail the heating efficiency of manufactured homes. Only six homes were included in this study because of budgetary constraints; therefore this is not a representative sample. These investigations do provide some useful information on the heating efficiency of these homes. Useful comparisons can be drawn between these study homes and site-built heating efficiencies measured with a similar protocol. The protocol used to test these homes is very similar to another Ecotope protocol used in the study conducted in 1992 and 1993 for the Bonneville Power Administration to test the heating efficiency of 24 homes. This protocol combined real-time power measurements of furnace energy usage with energy usage during co-heat periods. Accessory data such as house and duct tightness measurements and tracer gas measurements were used to describe these homes and their heating system efficiency. Ensuring that manufactured housing is constructed in an energy and resource efficient manner is of increasing concern to manufactured home builders and consumers. No comparable work has been done to measure the heating system efficiency of MCS manufactured homes, although some co-heat tests have been performed on manufactured homes heated with natural gas to validate HUD thermal standards. It is expected that later in 1994 more research of this kind will be conducted, and perhaps a less costly and less time-consuming method for testing efficiencies will be develops.
Davis, Bob; Palmiter, Larry S.; Siegel, Jeff
Estimating Costs and Efficiency of Storage, Demand, and Heat Pump Water
Estimating Costs and Efficiency of Storage, Demand, and Heat Pump Estimating Costs and Efficiency of Storage, Demand, and Heat Pump Water Heaters Estimating Costs and Efficiency of Storage, Demand, and Heat Pump Water Heaters June 14, 2012 - 7:38pm Addthis A water heater's energy efficiency is determined by the energy factor (EF), which is based on the amount of hot water produced per unit of fuel consumed over a typical day. The higher the energy factor, the more efficient the water heater. A water heater's energy efficiency is determined by the energy factor (EF), which is based on the amount of hot water produced per unit of fuel consumed over a typical day. The higher the energy factor, the more efficient the water heater. What does this mean for me? Estimate the annual operating costs and compare several water heaters to determine whether it is worth investing in a more efficient
Building Technologies Office: High Efficiency, Low Emission Supermarket
High Efficiency, Low High Efficiency, Low Emission Supermarket Refrigeration Research Project to someone by E-mail Share Building Technologies Office: High Efficiency, Low Emission Supermarket Refrigeration Research Project on Facebook Tweet about Building Technologies Office: High Efficiency, Low Emission Supermarket Refrigeration Research Project on Twitter Bookmark Building Technologies Office: High Efficiency, Low Emission Supermarket Refrigeration Research Project on Google Bookmark Building Technologies Office: High Efficiency, Low Emission Supermarket Refrigeration Research Project on Delicious Rank Building Technologies Office: High Efficiency, Low Emission Supermarket Refrigeration Research Project on Digg Find More places to share Building Technologies Office: High
Highly Efficient Silicon Light Emitting Diode
In this paper, we describe the fabrication, using standard silicon processing techniques, of silicon light-emitting diodes (LED) that efficiently emit photons with energy around the silicon bandgap. The improved efficiency had been explained by the spatial confinement of charge carriers due to a local strain field that is formed by dislocation loop arrays. The dependence of device electroluminescent properties on the annealing conditions is carefully examined as a high temperature process has profound influence on these dislocations. Increased luminescent intensity at higher device temperature, together with pure diffusion current conduction mechanism evidently shows the influence of the dislocation loops. The electrical properties of the diode are reasonable with low leakage reverse current.
Leminh Holleman Wallinga; P. Leminh; J. Holleman; H. Wallinga
Energy Efficiency Opportunities in Federal High Performance Computing Data Centers
Case study describes an outline of energy efficiency opportunities in federal high performance computing data centers.
Comparison of the high temperature heat flux sensor to traditional heat flux gages under high heat flux conditions.
Four types of heat flux gages (Gardon, Schmidt-Boelter, Directional Flame Temperature, and High Temperature Heat Flux Sensor) were assessed and compared under flux conditions ranging between 100-1000 kW/m2, such as those seen in hydrocarbon fire or propellant fire conditions. Short duration step and pulse boundary conditions were imposed using a six-panel cylindrical array of high-temperature tungsten lamps. Overall, agreement between all gages was acceptable for the pulse tests and also for the step tests. However, repeated tests with the HTHFS with relatively long durations at temperatures approaching 1000%C2%B0C showed a substantial decrease (10-25%) in heat flux subsequent to the initial test, likely due to the mounting technique. New HTHFS gages have been ordered to allow additional tests to determine the cause of the flux reduction.
Blanchat, Thomas K.; Hanks, Charles R.
Optimization of Combustion Efficiency for Supplementally Fired Gas Turbine Cogenerator Exhaust Heat Receptors
A broad range of unique cogeneration schemes are being installed or considered for application in the process industries involving gas turbines with heat recovery from the exhaust gas. Depending on the turbine design, exhaust gases will range from 800 to 1000 F with roughly 15 to 18 percent remaining oxygen. The overall heat utilization efficiency and the net effective heat rate of the cogenerating facility varies widely with the degree of supplemental firing of the heat receptor. This effect is explained and its economic significance defined. Other effects are also explored, such as adiabatic and equilibrium combustion temperatures; and variations in radiant versus convection heat transfer in the heat receptor furnace or boiler.
Waterland, A. F.
High efficiency compressor uses direct drive
This article focuses on the high efficiency of a compressor which uses only direct drive. This compressor was evaluated by judges and won Top Honors in the 1982 Chemical Processing magazine Vaaler Awards category of compressors, blowers and fans. Applications for the compressor include combustion air, process air and gas booster, incineration, fermentation, and vacuum filtration systems. In addition to a 50% reduction in power comsumption, the use of the compressor eliminated the need for a water seal, thus saving 200 gpm of water. And, since the elimination of the water seal reduced the necessary downtime for seal maintenance, on stream time was increased by 5%.
Union Power Cooperative - Residential Energy Efficient Heat Pump...
Cooling Heat Pumps Maximum Rebate 7,500 Program Information North Carolina Program Type Utility Loan Program Rebate Amount up to 7,500 Union Power Cooperative offers low...
High-efficiency concentrator silicon solar cells
This report presents results from extensive process development in high-efficiency Si solar cells. An advanced design for a 1.56-cm{sup 2} cell with front grids achieved 26% efficiency at 90 suns. This is especially significant since this cell does not require a prismatic cover glass. New designs for simplified backside-contact solar cells were advanced from a status of near-nonfunctionality to demonstrated 21--22% for one-sun cells in sizes up to 37.5 cm{sup 2}. An efficiency of 26% was achieved for similar 0.64-cm{sup 2} concentrator cells at 150 suns. More fundamental work on dopant-diffused regions is also presented here. The recombination vs. various process and physical parameters was studied in detail for boron and phosphorous diffusions. Emitter-design studies based solidly upon these new data indicate the performance vs design parameters for a variety of the cases of most interest to solar cell designers. Extractions of p-type bandgap narrowing and the surface recombination for p- and n-type regions from these studies have a generality that extends beyond solar cells into basic device modeling. 68 refs., 50 figs.
Sinton, R.A.; Cuevas, A.; King, R.R.; Swanson, R.M. (Stanford Univ., CA (USA). Solid-State Electronics Lab.)
Study of the design Method of an Efficient Ground Source Heat Pump Thermal Source System in a Cold Area
The ground source heat pump (GSHP) system-an energy efficiency and environment friendly system-is becoming popular in many parts of China. However, an imbalance usually exists between the annual heat extracted from and rejected to the ground due to the different heating and cooling load of a building, which will consistently deteriorate the heat pump efficiency leading even to the breakdown of the heat pump. This paper brings forward a design method of adding supplemental heat rejection equipment, a cooling tower, in the system to solve the problem in a cold area. Taking an office building in Beijing as an example, the authors simulate the GSHP system with two different connection methods between the cooling tower and vertical buried-pipe heat exchangers (in series and in parallel) using TRNSYS simulation software, and put forward several design schemes that can ensure the whole system continually operates with high efficiency. This also makes it possible to perform a more detailed economic optimization of the GSHP-based system in the future.
Shu, H.; Duanmu, L.; Hua, R.; Zou, Y.; Du, G.
High Efficiency, Illumination Quality OLEDs for Lighting
The goal of the program was to demonstrate a 45 lumen per watt white light device based upon the use of multiple emission colors through the use of solution processing. This performance level is a dramatic extension of the team's previous 15 LPW large area illumination device. The fundamental material system was based upon commercial polymer materials. The team was largely able to achieve these goals, and was able to deliver to DOE a 90 lumen illumination source that had an average performance of 34 LPW a 1000 cd/m{sup 2} with peak performances near 40LPW. The average color temperature is 3200K and the calculated CRI 85. The device operated at a brightness of approximately 1000cd/m{sup 2}. The use of multiple emission colors particularly red and blue, provided additional degrees of design flexibility in achieving white light, but also required the use of a multilayered structure to separate the different recombination zones and prevent interconversion of blue emission to red emission. The use of commercial materials had the advantage that improvements by the chemical manufacturers in charge transport efficiency, operating life and material purity could be rapidly incorporated without the expenditure of additional effort. The program was designed to take maximum advantage of the known characteristics of these material and proceeded in seven steps. (1) Identify the most promising materials, (2) assemble them into multi-layer structures to control excitation and transport within the OLED, (3) identify materials development needs that would optimize performance within multilayer structures, (4) build a prototype that demonstrates the potential entitlement of the novel multilayer OLED architecture (5) integrate all of the developments to find the single best materials set to implement the novel multilayer architecture, (6) further optimize the best materials set, (7) make a large area high illumination quality white OLED. A photo of the final deliverable is shown. In 2003, a large area, OLED based illumination source was demonstrated that could provide light with a quality, quantity, and efficiency on par with what can be achieved with traditional light sources. The demonstration source was made by tiling together 16 separate 6-inch x 6-inch blue-emitting OLEDs. The efficiency, total lumen output, and lifetime of the OLED based illumination source were the same as what would be achieved with an 80 watt incandescent bulb. The devices had an average efficacy of 15 LPW and used solution-processed OLEDs. The individual 6-inch x 6-inch devices incorporated three technology strategies developed specifically for OLED lighting -- downconversion for white light generation, scattering for outcoupling efficiency enhancement, and a scalable monolithic series architecture to enable large area devices. The downconversion approach consists of optically coupling a blue-emitting OLED to a set of luminescent layers. The layers are chosen to absorb the blue OLED emission and then luminescence with high efficiency at longer wavelengths. The composition and number of layers are chosen so that the unabsorbed blue emission and the longer wavelength re-emission combine to make white light. A downconversion approach has the advantage of allowing a wide variety of colors to be made from a limited set of blue emitters. In addition, one does not have to carefully tune the emission wavelength of the individual electro-luminescent species within the OLED device in order to achieve white light. The downconversion architecture used to develop the 15LPW large area light source consisted of a polymer-based blue-emitting OLED and three downconversion layers. Two of the layers utilized perylene based dyes from BASF AG of Germany with high quantum efficiency (>98%) and one of the layers consisted of inorganic phosphor particles (Y(Gd)AG:Ce) with a quantum efficiency of {approx}85%. By independently varying the optical density of the downconversion layers, the overall emission spectrum could be adjusted to maximize performance for lighting (e.g. blackbody temp
Joseph Shiang; James Cella; Kelly Chichak; Anil Duggal; Kevin Janora; Chris Heller; Gautam Parthasarathy; Jeffery Youmans; Joseph Shiang
Energy Efficiency Opportunities within the Heat Treatment Industry.
??Energy efficiency measures have become a top priority for large energy consuming companies because of the increasing energy prices and implemented energy policies. Many companies� (more)
K�llen, Malin
Heat exchanger with transpired, highly porous fins
The heat exchanger includes a fin and tube assembly with increased heat transfer surface area positioned within a hollow chamber of a housing to provide effective heat transfer between a gas flowing within the hollow chamber and a fluid flowing in the fin and tube assembly. A fan is included to force a gas, such as air, to flow through the hollow chamber and through the fin and tube assembly. The fin and tube assembly comprises fluid conduits to direct the fluid through the heat exchanger, to prevent mixing with the gas, and to provide a heat transfer surface or pathway between the fluid and the gas. A heat transfer element is provided in the fin and tube assembly to provide extended heat transfer surfaces for the fluid conduits. The heat transfer element is corrugated to form fins between alternating ridges and grooves that define flow channels for directing the gas flow. The fins are fabricated from a thin, heat conductive material containing numerous orifices or pores for transpiring the gas out of the flow channel. The grooves are closed or only partially open so that all or substantially all of the gas is transpired through the fins so that heat is exchanged on the front and back surfaces of the fins and also within the interior of the orifices, thereby significantly increasing the available the heat transfer surface of the heat exchanger. The transpired fins also increase heat transfer effectiveness of the heat exchanger by increasing the heat transfer coefficient by disrupting boundary layer development on the fins and by establishing other beneficial gas flow patterns, all at desirable pressure drops.
Kutscher, Charles F. (Golden, CO); Gawlik, Keith (Boulder, CO)
Office of Scientific and Technical Information (OSTI)
WHITE LED WITH HIGH PACKAGE WHITE LED WITH HIGH PACKAGE EXTRACTION EFFICIENCY Final Report Report Period Start Date: 10/01/2006 Report Period End Date: 09/30/2008 Authors: Yi Zheng and Matthew Stough Report Submission Date: November 2008 DOE Award Number: DE-FC26-06NT42935 Project Manager: Ryan Egidi OSRAM SYLVANIA Product Inc Central Research and Service Laboratory 71 Cherry Hill Dr., Beverly, MA 01915 2 DISCLAIMER This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor an agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus,
Design and global optimization of high-efficiency thermophotovoltaic systems
Despite their great promise, small experimental thermophotovoltaic (TPV) systems at 1000 K generally exhibit extremely low power conversion efficiencies (approximately 1%), due to heat losses such as thermal emission of ...
Bermel, Peter A.
System Effects of High Efficiency Filters in Homes
System Effects of High Efficiency Filters in Homes System Effects of High Efficiency Filters in Homes Title System Effects of High Efficiency Filters in Homes Publication Type Conference Paper LBNL Report Number LBNL-6144E Year of Publication 2013 Authors Walker, Iain S., Darryl J. Dickerhoff, David Faulkner, and William J. N. Turner Conference Name ASHRAE Annual Conference Date Published 03/2013 Abstract Occupant concern about indoor air quality (IAQ) issues has led to the increased use of more effective air filters in residential heating and cooling systems. A drawback of improved filtration is that better filters tend to have more flow resistance. This can lead to lower system airflows that reduce heat exchanger efficiency, increase duct pressure that leads to increased air leakage for ducts and, in some case s, increased blower power consumption. There is currently little knowledge on the magnitude of these effects. In this study, the performance of ten central forced air systems was monitored for a year. The systems used either a Permanent Split Capacitor (PSC) or a Brushless Permanent Magnet (BPM) blower. Each system was operated with a range of filter efficiencies ranging from MERV 6 (the lowest currently permitted in ASHRAE Standard 62.2) up to MERV 16. Measurements were recorded every ten seconds for blower power, filter pressure drop, supply and return plenum pressures together with plenum and indoor temperatures. These detailed continuous measurements allowed observation of filter loading effects as well as the initial change in system performance when filters were swapped. The results of the field measurements were used in simulations to examine more general system performance effects for a wider range of climates. The field tests showed that system static pressures were highly influenced by filter selection, filter loading rates varied more from house to house than by MERV rating and overall were quite low in many of the homes. PSC motors showed reduced power and airflow as the filters loaded, but BPM motors attempted to maintain a constant airflow and increased their power to do so. The combined field test and simulation results from this study indicate that for MERV 10-13 filters the effects on energy use are small (5%) and usability. In systems using low MERV filters that are already close to blower performance limits the addition of a MERV 16 filter pushed the blowers to their performance limits.
Novel Nanophosphors for High Efficiency Fluorescent Lamps
This is the Final Report of the Novel Nanophosphors for High Efficiency Fluorescent Lamps, Department of Energy (DOE). The overall goal of this three-year program is to develop novel hybrid phosphors by coating commercially available lamp phosphors with highly stable wide band-gap nanocrystalline phosphors (NCP). The prime technical approach is the development of NCP quantum-splitting phosphor (QSP) and ultra-violet (UV) emitting phosphors with quantum efficiencies exceeding that of the conventional phosphors at 185 nm. The novel hybrid phosphors will increase the efficiency of the fluorescent lamps by up to 32%, enabling total energy savings of 0.26 quads, the reduction in the U.S. energy bill by $6.5 billion and the reduction of the annual carbon emission by 4.1 billion kilogram. Our work started by investigating through modeling calculations the requirement for the particle size of the NCP. Our work to develop suitable nanocrystalline phosphors started with the known oxide quantum splitting and UV emitting phosphors. We demonstrated several synthesis techniques for the production of high quality nanocrystalline materials that crystallizes in the desired phase and with the desired particle size. In collaboration with our subcontractor we demonstrated the feasibility for the manufacture of NC phosphors. We also demonstrated novel techniques of coating the NCP on the surface of micron sized phosphors. Our chief achievement pertains to the successful testing of the coated hybrid phosphor systems in linear fluorescent lamps. In linear fluorescent lamp tests, we have demonstrated up to 7% increase in the efficacy of hybrid phosphors over the conventional (uncoated) phosphors. We have also demonstrated the improvement in the lumen maintenance of the coated phosphors. A hybrid phosphor system based on the commercial red emitting phosphor, Y{sub 2}O{sub 3}:Eu{sup 3+} did not show the anticipated improvement in lamp efficacy. We explored the reasons for this observation, which are detailed in this report. Within the program we have carried out fundamental investigations into the physical processes that determine the quantum splitting behavior of the Pr{sup 3+} ion in solids. Specifically, we have investigated the quantum splitting luminescence of this ion in the LaPO{sub 4}, SrAl{sub 12}O{sub 19} and LiLaP{sub 4}O{sub 12} host lattices. In this final report we summarize the technical work completed under the Program, summarize our findings about the performance limits of the various technologies we investigated, and outline promising paths for future work.
Alok Srivatava
| Chart credit ENERGY STAR Estimating the Cost and Energy Efficiency of a Solar Water Heater Diagram of a tankless water heater. Tankless or Demand-Type Water Heaters Water...
Improving Real World Efficiency of High Performance Buildings
Improving Real World Efficiency of High Performance Buildings Buildings End-Use Energy Efficiency Research www.energy.ca.gov/research/buildings February 2012 The Issue Highperformance buildings efficiency in highperformance buildings, however, are not always realized in practice. Addressing
Energy Efficient Heat Treatment for Linerless Hypereutectic Al-Si ...
Heat treatment standards developed by the aluminum industry over the last several decades are often not ... Vacuum HPDC of an actual hypereutectic Al-20 %Si motorcycle engine block con- ... formance and reducing oil consumption (Ref 1, 4, 6). The ... the specific cast component sections that are of research and.
Efficient energy supply from ground coupled heat transfer source
The increasing demands of Energy for industrial production and urban facilities, asks for new strategies for Energy sources. In recent years an important problem is to have some energy storage, energy production and energy consumption which fulfill some ... Keywords: heat, thermal aquifer, thermal energy
Maurizio Carlini; Sonia Castellucci
Results of a field test of heating system efficiency and thermal distribution system efficiency in a manufactured home
A two-day test using electric coheating was performed on a manufactured home in Watertown, New York. The main objective of the test was to evaluate planned procedures for measuring thermal distribution system efficiency. (Thermal distribution systems are the ductwork or piping used to transport heat or cooling effect from the equipment that produces it to the building spaces in which it is used.) These procedures are under consideration for a standard method of test now being prepared by a special committee of the American Society of Heating, Refrigerating, and Air-Conditioning Engineers. The ability of a coheating test to give a credible and repeatable value for the overall heating system efficiency was supported by the test data. Distribution efficiency is derived from system efficiency by correcting for energy losses from the equipment. Alternative means for achieving this were tested and assessed. The best value for system efficiency in the Watertown house was 0.53, while the best value for distribution efficiency was 0.72.
Andrews, J.W.; Krajewski, R.F.; Strasser, J.J. [Brookhaven National Lab., Upton, NY (United States); Kinney, L.; Lewis, G. [Synertech Systems Corp., Syracuse, NY (United States)
Generation of a Parabolic Trough Collector Efficiency Curve from Separate Measurements of Outdoor Optical Efficiency and Indoor Receiver Heat Loss
The thermal efficiency of a parabolic trough collector is a function of both the fraction of direct normal radiation absorbed by the receiver (the optical efficiency) and the heat lost to the environment when the receiver is at operating temperature. The thermal efficiency can be determined by testing the collector under actual operating conditions or by separately measuring these two components. This paper describes how outdoor measurement of the optical efficiency is combined with laboratory measurements of receiver heat loss to obtain the thermal efficiency curve. This paper describes this approach and also makes the case that there are advantages to plotting collector efficiency versus the difference between the operating temperature and the ambient temperature at which the receiver heat loss was measured divided by radiation to a fractional power (on the order of 1/3 but obtained via data regression) - as opposed to the difference between operating and ambient temperatures divided by the radiation. The results are shown to be robust over wide ranges of ambient temperature, sky temperature, and wind speed.
Kutscher, C.; Burkholder, F.; Stynes, J. K.
Analysis of space heating and domestic hot water systems for energy-efficient residential buildings
An analysis of the best ways of meeting the space heating and domestic hot water (DHW) needs of new energy-efficient houses with very low requirements for space heat is provided. The DHW load is about equal to the space heating load in such houses in northern climates. The equipment options which should be considered are discussed, including new equipment recently introduced in the market. It is concluded that the first consideration in selecting systems for energy-efficient houses should be identification of the air moving needs of the house for heat distribution, heat storage, ventilation, and ventilative cooling. This is followed, in order, by selection of the most appropriate distribution system, the heating appliances and controls, and the preferred energy source, gas, oil, or electricity.
Dennehy, G
Tailored Materials for High Efficiency CIDI Engines
The overall goal of the project, Tailored Materials for High Efficiency Compression Ignition Direct Injection (CIDI) Engines, is to enable the implementation of new combustion strategies, such as homogeneous charge compression ignition (HCCI), that have the potential to significantly increase the energy efficiency of current diesel engines and decrease fuel consumption and environmental emissions. These strategies, however, are increasing the demands on conventional engine materials, either from increases in peak cylinder pressure (PCP) or from increases in the temperature of operation. The specific objective of this project is to investigate the application of a new material processing technology, friction stir processing (FSP), to improve the thermal and mechanical properties of engine components. The concept is to modify the surfaces of conventional, low-cost engine materials. The project focused primarily on FSP in aluminum materials that are compositional analogs to the typical piston and head alloys seen in small- to mid-sized CIDI engines. Investigations have been primarily of two types over the duration of this project: (1) FSP of a cast hypoeutectic Al-Si-Mg (A356/357) alloy with no introduction of any new components, and (2) FSP of Al-Cu-Ni alloys (Alloy 339) by physically stirring-in various quantities of carbon nanotubes/nanofibers or carbon fibers. Experimental work to date on aluminum systems has shown significant increases in fatigue lifetime and stress-level performance in aluminum-silicon alloys using friction processing alone, but work to demonstrate the addition of carbon nanotubes and fibers into aluminum substrates has shown mixed results due primarily to the difficulty in achieving porosity-free, homogeneous distributions of the particulate. A limited effort to understand the effects of FSP on steel materials was also undertaken during the course of this project. Processed regions were created in high-strength, low-alloyed steels up to 0.5 in. deep that showed significant grain refinement and homogeneous microstructures favorable to increased fracture toughness and fatigue performance. The final tasks of the project demonstrated that the FSP concept can be applied to a relevant part geometry by fabricating diesel piston crowns with FSP regions applied selectively to the edge of the bowl rim. This area of the piston typically suffers from conditions at high PCP that cause severe thermal fatigue issues. It is expected that, given the data from coupon testing, the durability of pistons modified by FSP will allow much higher fatigue lifetime and potentially also greater resistance to elevated stress-level effects on fatigue.
Grant, G.J.; Jana, S.
High temperature heat pipe experiments in low earth orbit
Although high temperature, liquid metal heat pipe radiators have become a standard component on most high power space power system designs, there is no experimental data on the operation of these heat pipes in a zero gravity or micro-gravity environment. Experiments to benchmark the transient and steady state performance of prototypical heat pipe space radiator elements are in preparation for testing in low earth orbit. It is anticipated that these heat pipes will be tested aborad the Space Shuttle in 1995. Three heat pipes will be tested in a cargo bay Get Away Special (GAS) canister. The heat pipes are SST/potassium, each with a different wick structure; homogeneous, arterial, and annular gap, the heat pipes have been designed, fabricated, and ground tested. In this paper, the heat pipe designs are specified, and transient and steady-state ground test data are presented.
Woloshun, K.; Merrigan, M.A.; Sena, J.T. (Los Alamos National Lab., NM (United States)); Critchley, E. (Phillips Lab., Kirtland AFB, NM (United States))
Woloshun, K.; Merrigan, M.A.; Sena, J.T. [Los Alamos National Lab., NM (United States); Critchley, E. [Phillips Lab., Kirtland AFB, NM (United States)
Policy Supporting Energy Efficiency and Heat Pump Technology
information: lifetime, adoption rate, code/standard date, etc. We apply standard analysis methodology: · Energy savings (technical potential): maximum technical savings is percent savings multiplied by market of energy efficient appliances and equipment Market Stimulation · Identify barriers to "speed and scale
High efficiency photodetection below the quantum noise limit
Two low-noise, high quantum efficiency, high bandwidth photodetectors have constructed to form a balanced homodyne detector to detect squeezed light. The detectors have quantum efficiencies of 85% and 90%, a bandwidth of ...
Bullard, Elizabeth Caryn
Fuel Cell/Turbine Ultra High Efficiency Power System
FuelCell Energy, INC. (FCE) is currently involved in the design of ultra high efficiency power plants under a cooperative agreement (DE-FC26-00NT40) managed by the National Energy Technology Laboratory (NETL) as part of the DOE's Vision 21 program. Under this project, FCE is developing a fuel cell/turbine hybrid system that integrates the atmospheric pressure Direct FuelCell{reg_sign} (DFC{reg_sign}) with an unfired Brayton cycle utilizing indirect heat recovery from the power plant. Features of the DFC/T{trademark} system include: high efficiency, minimal emissions, simplicity in design, direct reforming internal to the fuel cell, no pressurization of the fuel cell, independent operating pressure of the fuel cell and turbine, and potential cost competitiveness with existing combined cycle power plants at much smaller sizes. Objectives of the Vision 21 Program include developing power plants that will generate electricity with net efficiencies approaching 75 percent (with natural gas), while producing sulfur and nitrogen oxide emissions of less than 0.01 lb/million BTU. These goals are significant improvements over conventional power plants, which are 35-60 percent efficient and produce emissions of 0.07 to 0.3 lb/million BTU of sulfur and nitrogen oxides. The nitrogen oxide and sulfur emissions from the DFC/T system are anticipated to be better than the Vision 21 goals due to the non-combustion features of the DFC/T power plant. The expected high efficiency of the DFC/T will also result in a 40-50 percent reduction in carbon dioxide emissions compared to conventional power plants. To date, the R&D efforts have resulted in significant progress including proof-of-concept tests of a sub-scale power plant built around a state-of-the-art DFC stack integrated with a modified Capstone Model 330 Microturbine. The objectives of this effort are to investigate the integration aspects of the fuel cell and turbine and to obtain design information and operational data that will be utilized in the design of a 40-MW high efficiency Vision 21 power plant. Additionally, these tests are providing the valuable insight for DFC/Turbine power plant potential for load following, increased reliability, and enhanced operability.
Hossein, Ghezel-Ayagh
Rotating Heat Transfer in High Aspect Ratio Rectangular Cooling...
Reynolds Number (Nu Nu o ) (f f o ) 24% Increase in Cooling Performance Rotating Heat Transfer in High Aspect Ratio Rectangular Cooling Passages with Shaped Turbulators...
Creep Behavior of High Temperature Alloys for Intermediate Heat ...
Presentation Title, Creep Behavior of High Temperature Alloys for Intermediate Heat Exchanger in Next Generation Nuclear Plant. Author(s), Xingshuo Wen,�...
Thulium heat source for high-endurance and high-energy density power systems
We are studying the performance characteristics of radioisotope heat source designs for high-endurance and high-energy-density power systems that use thulium-170. Heat sources in the power range of 5--50 kW{sub th} coupled with a power conversion efficiency of {approximately}30%, can easily satisfy current missions for autonomous underwater vehicles. New naval missions will be possible because thulium isotope power systems have a factor of one-to-two hundred higher endurance and energy density than chemical and electrochemical systems. Thulium-170 also has several other attractive features, including the fact that it decays to stable ytterbium-170 with a half-life of four months. For terrestrial applications, refueling on that time scale should be acceptable in view of the advantage of its benign decay. The heat source designs we are studying account for the requirements of isotope production, shielding, and integration with power conversion components. These requirements are driven by environmental and safety considerations. Thulium is present in the form of thin refractory thulia disks that allow power conversion at high peak temperature. We give estimates of power system state points, performance, mass, and volume characteristics. Monte Carlo radiation analysis provides a detailed assessment of shield requirements and heat transfer under normal and distressed conditions is also considered. 11 refs., 7 figs., 4 tabs.
Walter, C.E.; Kammeraad, J.E.; Van Konynenburg, R.; VanSant, J.H.
High Efficiency Organic Light Emitting Devices for Lighting
Incorporate internal scattering layers and microlens arrays in high efficiency OLED to achieve up to 70% EQE.
So, Franky; Tansu, Nelson; Gilchrist, James
High Efficiency Electrical Energy Storage Using Reversible Solid ...
Symposium, Energy Storage III: Materials, Systems and Applications Symposium. Presentation Title, High Efficiency Electrical Energy Storage Using Reversible�...
High Efficiency Low Emission Supermarket Refrigeration Research Project
The U.S. Department of Energy (DOE) is currently conducting research into high efficiency, low emission supermarket refrigeration technologies.
Analysis of highly-efficient electric residential HPWHs
A scoping level analysis was conducted to identify electric HPWH concepts that have the potential to achieve or exceed 30% source energy savings compared to a gas tankless water heater (GTWH) representative of the type represented in version 0.9.5.2 beta of the BEopt software developed by the National Renewable Energy Laboratory. The analysis was limited to evaluation of options to improve the energy efficiency of electric HPWH product designs currently on the market in the US. The report first defines the baseline GTWH system and determines its efficiency (source-energy-based adjusted or derated EF of ~0.71). High efficiency components (compressors, pumps, fans, heat exchangers, etc.) were identified and applied to current US HPWH products and analyzed to determine the viability of reaching the target EF. The target site-based energy factor (EF) required for an electric HPWH necessary to provide 30% source energy savings compared to the GTWH baseline unit is then determined to be ~3.19.
Baxter, Van D [ORNL; Murphy, Richard W [ORNL; Rice, C Keith [ORNL; Shen, Bo [ORNL; Gao, Zhiming [ORNL
Predicting HHFW Heating Efficiency on NSTX via Whole-Device Full-Wave Simulation
We present a qualitative comparison of NSTX HHFW heating efficiency observations with results from the AORSA whole-device, linear simulation. The simulation retains a realistic geometry and core plasma kinetic physics such that scrape-off plasma linear RF fields can be calculated. By examining L-mode and neutral beam heated H-mode scenarios we quantify the conditions that result in a fast-wave coaxial mode in the scrape-off plasma. These large amplitude coaxial modes are expected to damp on collisions or couple to non-linear damping mechanisms and be correlated to an observed drop in core heating efficiency.
Green, D. L.; Berry, L. A.; Ryan, P. M. [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, Tennessee 37831-6169 (United States); Jaeger, E. F. [XCEL Engineering Inc., 1066 Commerce Park Dr., Oak Ridge, TN 37830 (United States)
Development program for heat balance analysis fuel to steam efficiency boiler and data wireless transfer
This research aim to improve a combustion system of boiler within increase combustion efficiency and use all out of the energy. The large boilers were used in the industrial factories which consume a lot of energy for production. By oil and gas fuel ... Keywords: boiler, cogeneration energy, heat balance, steam efficiency, wireless data transfer
Nattapong Phanthuna; Warunee Srisongkram; Sunya Pasuk; Thaweesak Trongtirakul
Highly Efficient Multigap Solar Cell Materials
Scientists at Berkeley Lab have invented multiband gap semiconducting materials for developing solar cells that could achieve power conversion efficiencies of 50 percent or higher.
High efficiency, radiation-hard solar cells
The direct gap of the In{sub 1-x}Ga{sub x}N alloy system extends continuously from InN (0.7 eV, in the near IR) to GaN (3.4 eV, in the mid-ultraviolet). This opens the intriguing possibility of using this single ternary alloy system in single or multi-junction (MJ) solar cells of the type used for space-based surveillance satellites. To evaluate the suitability of In{sub 1-x}Ga{sub x}N as a material for space applications, high quality thin films were grown with molecular beam epitaxy and extensive damage testing with electron, proton, and alpha particle radiation was performed. Using the room temperature photoluminescence intensity as a indirect measure of minority carrier lifetime, it is shown that In{sub 1-x}Ga{sub x}N retains its optoelectronic properties at radiation damage doses at least 2 orders of magnitude higher than the damage thresholds of the materials (GaAs and GaInP) currently used in high efficiency MJ cells. This indicates that the In{sub 1-x}Ga{sub x}N is well-suited for the future development of ultra radiation-hard optoelectronics. Critical issues affecting development of solar cells using this material system were addressed. The presence of an electron-rich surface layer in InN and In{sub 1-x}Ga{sub x}N (0 < x < 0.63) was investigated; it was shown that this is a less significant effect at large x. Evidence of p-type activity below the surface in Mg-doped InN was obtained; this is a significant step toward achieving photovoltaic action and, ultimately, a solar cell using this material.
Ager III, J.W.; Walukiewicz, W.
Center for Energy Efficiency and Renewable Energy at University of Massachusetts 3D Model of Heat Transfer and Fluid3D Model of Heat Transfer and Fluid
Center for Energy Efficiency and Renewable Energy at University of Massachusetts 3D Model of Heat for Energy Efficiency and Renewable Energy at University of Massachusetts 3D Model of Heat Transfer and Fluid WindowModeling a 3D Window Future WorkFuture Work #12;Center for Energy Efficiency and Renewable Energy
Massachusetts at Amherst, University of
Advanced Thermoelectric Materials for Efficient Waste Heat Recovery in Process Industries
The overall objective of the project was to integrate advanced thermoelectric materials into a power generation device that could convert waste heat from an industrial process to electricity with an efficiency approaching 20%. Advanced thermoelectric materials were developed with figure-of-merit ZT of 1.5 at 275 degrees C. These materials were not successfully integrated into a power generation device. However, waste heat recovery was demonstrated from an industrial process (the combustion exhaust gas stream of an oxyfuel-fired flat glass melting furnace) using a commercially available (5% efficiency) thermoelectric generator coupled to a heat pipe. It was concluded that significant improvements both in thermoelectric material figure-of-merit and in cost-effective methods for capturing heat would be required to make thermoelectric waste heat recovery viable for widespread industrial application.
Adam Polcyn; Moe Khaleel
Industrial Waste Heat Recovery Opportunities: An Update on Industrial High Temperature Heat Pump Technologies
It is estimated that as much as 20% to 50% of energy consumed is lost via waste heat contained in streams of exhaust gases and hot liquids, as well as through conduction, convection or radiation emanating from the surface of hot equipment. It is also estimated that in some cases, such as industrial furnaces, efficiency improvements resulting from waste heat recovery can improve efficiency by 10% to as much as 50%. This technical update is a continuation of research conducted by the Electric Power ...
Heat Budget of the Siberian High and the Winter Monsoon
The heat budget of the Siberian high is investigated by using a compositing method. Ninteen cases of strong Siberian highs that moved over China from the northwest were selected from datasets covering five winters (December through February of ...
Yihui Ding; T. N. Krishnamurti
Microgrids: An emerging paradigm for meeting building electricityand heat requirements efficiently and with appropriate energyquality
The first major paradigm shift in electricity generation,delivery, and control is emerging in the developed world, notably Europe,North America, and Japan. This shift will move electricity supply awayfrom the highly centralised universal service quality model with which weare familiar today towards a more dispersed system with heterogeneousqualities of service. One element of dispersed control is the clusteringof sources and sinks into semi-autonomous mu grids (microgrids).Research, development, demonstration, and deployment (RD3) of mu gridsare advancing rapidly on at least three continents, and significantdemonstrations are currently in progress. This paradigm shift will resultin more electricity generation close to end-uses, often involvingcombined heat and power application for building heating and cooling,increased local integration of renewables, and the possible provision ofheterogeneous qualities of electrical service to match the requirementsof various end-uses. In Europe, mu grid RD3 is entering its third majorround under the 7th European Commission Framework Programme; in the U.S.,one specific mu grid concept is undergoing rigorous laboratory testing,and in Japan, where the most activity exists, four major publiclysponsored and two privately sponsored demonstrations are in progress.This evolution poses new challenges to the way buildings are designed,built, and operated. Traditional building energy supply systems willbecome much more complex in at least three ways: 1. one cannot simplyassume gas arrives at the gas meter, electricity at its meter, and thetwo systems are virtually independent of one another; rather, energyconversion, heat recovery and use, and renewable energy harvesting mayall be taking place simultaneously within the building energy system; 2.the structure of energy flows in the building must accommodate multipleenergy processes in a manner that permits high overall efficiency; and 3.multiple qualities of electricity may be supplied to various buildingfunctions.
Marnay, Chris; Firestone, Ryan
Investigating potential light-duty efficiency improvements through simulation of turbo-compounding and waste-heat recovery systems
Modern diesel engines used in light-duty transportation applications have peak brake thermal efficiencies in the range of 40-42% for high-load operation with substantially lower efficiencies at realistic road-load conditions. Thermodynamic energy and exergy analysis reveals that the largest losses from these engines are due to combustion irreversibility and heat loss to the coolant, through the exhaust, and by direct convection and radiation to the environment. Substantial improvement in overall engine efficiency requires reducing or recovering these losses. Unfortunately, much of the heat transfer either occurs at relatively low temperatures resulting in large entropy generation (such as in the air-charge cooler), is transferred to low-exergy flow streams (such as the oil and engine coolant), or is radiated or convected directly to the environment. While there are significant opportunities for recovery from the exhaust and EGR cooler for heavy-duty applications, achieving similar benefits for light-duty applications is complicated by transient, low-load operation at typical driving conditions and competition with the turbocharger and aftertreatment system for the limited thermal resources. We have developed an organic Rankine cycle model using GT-Suite to investigate the potential for efficiency improvement through waste-heat recovery from the exhaust and EGR cooler of a light-duty diesel engine. The model is used to examine the effects of efficiency-improvement strategies such as cylinder deactivation, use of advanced materials and improved insulation to limit ambient heat loss, and turbo-compounding on the steady-state performance of the ORC system and the availability of thermal energy for downstream aftertreatment systems. Results from transient drive-cycle simulations are also presented, and we discuss strategies to address operational difficulties associated with transient drive cycles and balancing the thermal requirements of waste-heat recovery, turbocharging or turbo-compounding, and exhaust aftertreatment.
Edwards, Kevin Dean [ORNL; Wagner, Robert M [ORNL; Briggs, Thomas E [ORNL
New and Underutilized Technology: Efficient High Bay Fluorescent Lighting |
Efficient High Bay Fluorescent Efficient High Bay Fluorescent Lighting New and Underutilized Technology: Efficient High Bay Fluorescent Lighting October 7, 2013 - 8:54am Addthis The following information outlines key deployment considerations for efficient high bay fluorescent lighting within the Federal sector. Benefits Efficient high bay fluorescent lighting can include either T5 or T8 fluorescent lighting systems for high-bay applications currently using metal halide fixtures. Fluorescent fixtures offer better light distribution, better light maintenance over the life of the lamp, improved color quality, and on-off control (re-strike time) with lower energy consumption. Application Efficient high bay fluorescent lighting is applicable for facilities containing high bay areas. Key Factors for Deployment
Ecological and Economical efficient Heating and Cooling by innovative Gas Motor Heat Pump Systems and Solutions
options ·Universal application as an Air-Air System (VRF), Air-Water System or combined as a Mixed System application options · Option 1: Air-Air System (VRF) #12;· Option 2: Air-Air System (HVAC System) Gas Heat
High efficiency pulse motor drive for robotic propulsion
The goal of this research is to improve the power efficiency of robotic locomotion through the use of series elastic actuation, with a focus on swimming motion. To achieve high efficiency, electromechanical drives need to ...
Sun, Zhen, M.S. Massachusetts Institute of Technology
Techniques for high-efficiency outphasing power amplifiers
A trade-off between linearity and efficiency exists in conventional power amplifiers (PAs). The outphase amplifying concept overcomes this trade-off by enabling the use of high efficiency, non-linear power amplifiers for ...
Godoy, Philip (Philip Andrew)
Energy efficiency indicators for high electric-load buildings
Energy per unit of floor area is not an adequate indicator for energy efficiency in high electric-load buildings. For two activities, restaurants and computer centres, alternative indicators for energy efficiency are discussed.
Aebischer, Bernard; Balmer, Markus A.; Kinney, Satkartar; Le Strat, Pascale; Shibata, Yoshiaki; Varone, Frederic
Design of high efficiency Mid IR QCL lasers
The proposed research is a study of designing high-efficiency Mid-IR quantum cascade lasers (QCL). This thesis explores "injector-less" designs for achieving lower voltage defects and improving wall plug efficiencies through ...
Hsu, Allen Long
process efficiency (UoK, GA) · Estimate the size and cost of the process equipment (All) #12;s NERI H2 6 cycle analysis (SNL) · Develop detailed chemical flowsheet for selected process and determine projected UT-3 process is conceptually simple. . . l Invented at Univ. of Tokyo, being pursued in Japan, SI
2004 ASHRAE. 3 Standing column wells can be used as highly efficient
©2004 ASHRAE. 3 ABSTRACT Standing column wells can be used as highly efficient ground heat Performance Simon J. Rees, Ph.D. Jeffrey D. Spitler, Ph.D., P.E. Zheng Deng Member ASHRAE Member ASHRAE Student Member ASHRAE Carl D. Orio Carl N. Johnson, Ph.D. Member ASHRAE Member ASHRAE Simon J. Rees
Heat Pipe Embedded AlSiC Plates for High Conductivity - Low CTE Heat Spreaders
Heat pipe embedded aluminum silicon carbide (AlSiC) plates are innovative heat spreaders that provide high thermal conductivity and low coefficient of thermal expansion (CTE). Since heat pipes are two phase devices, they demonstrate effective thermal conductivities ranging between 50,000 and 200,000 W/m-K, depending on the heat pipe length. Installing heat pipes into an AlSiC plate dramatically increases the plate�s effective thermal conductivity. AlSiC plates alone have a thermal conductivity of roughly 200 W/m-K and a CTE ranging from 7-12 ppm/ deg C, similar to that of silicon. An equivalent sized heat pipe embedded AlSiC plate has effective thermal conductivity ranging from 400 to 500 W/m-K and retains the CTE of AlSiC.
Johnson, Matthew (DOE/NNSA Kansas City Plant (United States)); Weyant, J.; Garner, S. (Advanced Cooling Technologies, Inc. (Lancaster, PA (United States)); Occhionero, M. (CPS Technologies Corporation, Norton, MA (United States))
Seasonal efficiencies of residential heat pump air conditioners with inverter-driven compressors
This paper describes a study to experimentally determine the steady-state characteristics, cyclic effect, and frosting/defrosting effect of a inverter heat pump currently available on the Japanese market and compute its seasonal efficiency based on the local outdoor air temperature data. It has been found that the APF of this heat pump is higher by 15% than that of the conventional fixed-speed heat pump. If cyclic and frosting/defrosting losses are eliminated, the APF of the inverter heat pump will be further improved by 2% to 6%. For the evaluation of an inverter heat pump, APF alone is not sufficient, and an additional parameter such as an annual comfort factor (ACF) is needed.
Hori, M.; Akamine, I.; Sakai, T.
Personal Comfort Systems: Cooling/Heating Local Body Parts Efficient Ways
Personal Comfort Systems: Cooling/Heating Local Body Parts Efficient Ways Personal Comfort Systems: Cooling/Heating Local Body Parts Efficient Ways to Provide Comfort Indoors Speaker(s): Hui Zhang Date: October 9, 2012 - 12:00pm Location: 90-3122 Seminar Host/Point of Contact: Rongxin Yin This presentation describes energy efficient approaches to provide comfort in offices by creating non-uniform and transient thermal environments. The presentation will describe 1) distributions and characteristics of thermoreceptors of human body, 2) comfort responses of people exposed to complex thermal environments, 3) concept of "alliesthesia", 4) personal comfort systems developed by CBE, 5) their energy efficiency and demand response potential, and 6) the CBE advanced thermal comfort model. A recording of this seminar is available at: https://vimeo.com/51536661
Energy Efficiency Challenges in Heating Supply System of Turkmenistan and Potential Solutions
The poor condition and inefficient operation of the existing heat and hot water supply system in Turkmenistan is causing serious economic, social and environmental problems. Yet, the situation may very well change to the worse as increase of energy consumption is projected for near future. The country's commitment to reduce greenhouse gases emissions faces the challenge of ensuring that both the short- and long-term environmental impacts can be minimized while service levels of heat and hot water supply to the population are simultaneously improved. Despite the energy, economic, and environmental benefits of energy efficiency in Turkmenistan, little has been done to eliminate energy waste. Due historic legacy, there is a limited institutional capacity to increase energy efficiency. Achieving energy and environmental goals will require a basic institutional transformation. Gaps in polices and legislation in the area of energy efficiency and the lack capacity and institutional expertise in managing local, regional and national energy efficiency programs have to be addressed.
Zomov, A.; Behnke, R.
High-temperature waste-heat-stream selection and characterization
Four types of industrial high-temperature, corrosive waste heat streams are selected that could yield significant energy savings if improved heat recovery systems were available. These waste heat streams are the flue gases from steel soaking pits, steel reheat furnaces, aluminum remelt furnaces, and glass melting furnaces. Available information on the temperature, pressure, flow, and composition of these flue gases is given. Also reviewed are analyses of corrosion products and fouling deposits resulting from the interaction of these flue gases with materials in flues and heat recovery systems.
Wikoff, P.M.; Wiggins, D.J.; Tallman, R.L.; Forkel, C.E.
Development of a High Performance Air Source Heat Pump for the US Market
Heat pumps present a significant advantage over conventional residential heating technologies due to higher energy efficiencies and less dependence on imported oil. The US development of heat pumps dates back to the 1930 s with pilot units being commercially available in the 1950 s. Reliable and cost competitive units were available in the US market by the 1960 s. The 1973 oil embargo led to increased interest in heat pumps prompting significant research to improve performance, particularly for cold climate locations. Recent increasing concerns on building energy efficiency and environmental emissions have prompted a new wave of research in heat pump technology with special emphasis on reducing performance degradation at colder outdoor air temperatures. A summary of the advantages and limitations of several performance improvement options sought for the development of high performance air source heat pump systems for cold climate applications is the primary focus of this paper. Some recommendations for a high performance cold climate heat pump system design most suitable for the US market are presented.
Abdelaziz, Omar [ORNL; Shen, Bo [ORNL; Gao, Zhiming [ORNL; Baxter, Van D [ORNL; Iu, Ipseng [ORNL
A six-stroke engine cycle having improved efficiency. Heat is recovered from the engine combustion gases by using a 6-stroke engine cycle in which combustion gases are partially vented proximate the bottom-dead-center position of the fourth stroke cycle, and water is injected proximate the top-dead-center position of the fourth stroke cycle.
Szybist, James P; Conklin, James C
Seasonal Energy Efficiency Ratio (SEER) Investigation for Residential and Small Commercial Air-Source Heat Pumps
Electric utilities frequently use the seasonal energy efficiency ratio (SEER) in air conditioning�based incentive programs to categorize energy efficiency and to quantify financial value. For residential and small commercial unitary air conditioners and heat pumps, SEER is determined by the procedures outlined in ANSI/AHRI Standard 210/240. Within Standard 210/240, SEER is calculated based on laboratory test results and equations that follow specific assumptions regarding indoor temperature, ...
High Efficiency Low Emission Supermarket Refrigeration Research Project |
High Efficiency Low Emission Supermarket High Efficiency Low Emission Supermarket Refrigeration Research Project High Efficiency Low Emission Supermarket Refrigeration Research Project The U.S. Department of Energy (DOE) is currently conducting research into high efficiency, low emission supermarket refrigeration technologies. Project Description The project involves the development of a supermarket refrigeration system that can reduce greenhouse gas emissions and energy consumption when compared to existing systems. The challenge is to design a system that is capable of achieving low refrigerant leak rates while significantly reducing both the energy consumption and the refrigerant charge size. Project Partners Research is being undertaken between DOE and Oak Ridge National Laboratory. Project Goals
Available Technologies: High Efficiency Spiral RF-Induction ...
The spiral antennas efficient use of source geometry also ... Neutron and high energy gamma ... A typical RF-induction plasma generator with a ...
Titania Coated Silica Microspheres for High Efficiency Dye ...
These microspheres, if used in DSSCs, can boost the efficiency of solar cell ... In- situ Characterization of Intercalation-induced Damage of High Purity Graphite�...
Energy Efficiency in Mineral Processing Industry Using High ...
Presentation Title, Energy Efficiency in Mineral Processing Industry Using High ... These studies were prepared by Tetra Tech on eight different projects at�...
Low Cost, High Efficiency Tandem Silicon Solar Cells and LEDs
Wladek Walukiewicz, Joel Ager, and Kin Man Yu of Berkeley Lab have developed high-efficiency solar cells that leverage the well-established design and ...
High-Efficiency Photovoltaics at Thin Film Costs
Time (Years) 0-+ 5. 10. 15. 20. 25. Opportunity. Technology. ... � 15 years renewable energy business development ... High-Efficiency Photovoltaics at ...
Complex Oxides for Highly Efficient Solid-State Energy ...
Complex Oxides for Highly Efficient Solid-State Energy ... Using complex oxides to directly convert thermal to electrical energy is both ... Thermal P ...
Available Technologies: High Quantum Efficiency Charge-Coupled ...
Scientists at Berkeley Lab have developed a p-channel CCD with high quantum efficiency in the blue and near infrared wavelengths by combining a ...
Development of a High Efficiency Ceiling Fan
The potential of ceiling fans to improve comfort during the cooling season is well documented (Rohles et al.. 1983; Fairey et al.. 1986). There are at least two cases: In the first where air conditioning is unavailable, adding ceiling fans may significantly improve building comfort and health although actually increasing energy use. However, the more common circumstance is where ceiling fans are used with the objective of providing a higher cooling system thermostat set point with acceptable comfort. Fans can also potentially avoid the use of air conditioning during "swing" seasons. Although studies commonly suggest a 2-6OF increase in the thermostat set point, data from 386 surveyed Central Florida households suggests that although fans are used an average of 13.4 hours per day, no statistically valid difference can be observed in thermostat settings between households using fans and those without them (James et al., 1996). Part of this may be due to the lack of sufficiently wide air distribution coverage within rooms (Rohles et al, 1983; Sonne and Parker, 1998). Studies touting potential cooling savings of up to 40% have usually been sponsored by fan manufacturers (eg. A.D. Little, 1981). These often make unrealistic assumptions such as presuming that occupants are within four feet of a fan with only one fan in use and a 6�F elevation of the thermostat setting. An environmental chamber study by Consumer Reports showed that the long-reported de-stratification benefits when heating are largely unsubstantiated (Consumer Reports. 1993). Thus. benefits from ceiling fans are only to reduce cooling needs and this is completely contingent on sufficient changes in interior comfort to warrant raising of the cooling thermostat. Two other factors must be taken into account in assessing the benefits of fans: their actual energy use and the added internal heat gains produced by the fans during operation. The measured electrical demand of ceiling fans varies between 5 and 115 Watts depending on model and speed selection. A power demand of 40 W at medium speed is probably typical (Chandra, 1985). Thus, a fan used for six months of the year would use 175 kwh. With 4.3 ceiling fans in an average Florida home, this amounts to about 800 kwh of fan energy consumption --about 5% of total electricity use. Also, all of the energy use of fans is eventually converted to heat within the home which must eventually be removed by ventilation air or the cooling system.
Parker, D. S.; Callahan, M. P.; Sonne, J. K.; Su, G. H.; Hibbs, B. D.
High Efficiency, Low Emissions Homogeneous Charge Compression Ignition (HCCI) Engines
This is the final report of the High Efficiency Clean Combustion (HECC) Research Program for the U.S. Department of Energy. Work under this co-funded program began in August 2005 and finished in July 2010. The objective of this program was to develop and demonstrate a low emission, high thermal efficiency engine system that met 2010 EPA heavy-duty on-highway truck emissions requirements (0.2g/bhp-hr NOx, 0.14g/bhp-hr HC and 0.01g/bhp-hr PM) with a thermal efficiency of 46%. To achieve this goal, development of diesel homogenous charge compression ignition (HCCI) combustion was the chosen approach. This report summarizes the development of diesel HCCI combustion and associated enabling technologies that occurred during the HECC program between August 2005 and July 2010. This program showed that although diesel HCCI with conventional US diesel fuel was not a feasible means to achieve the program objectives, the HCCI load range could be increased with a higher volatility, lower cetane number fuel, such as gasoline, if the combustion rate could be moderated to avoid excessive cylinder pressure rise rates. Given the potential efficiency and emissions benefits, continued research of combustion with low cetane number fuels and the effects of fuel distillation are recommended. The operation of diesel HCCI was only feasible at part-load due to a limited fuel injection window. A 4% fuel consumption benefit versus conventional, low-temperature combustion was realized over the achievable operating range. Several enabling technologies were developed under this program that also benefited non-HCCI combustion. The development of a 300MPa fuel injector enabled the development of extended lifted flame combustion. A design methodology for minimizing the heat transfer to jacket water, known as precision cooling, will benefit conventional combustion engines, as well as HCCI engines. An advanced combustion control system based on cylinder pressure measurements was developed. A Well-to-wheels analysis of the energy flows in a mobile vehicle system and a 2nd Law thermodynamic analysis of the engine system were also completed under this program.
Generation of a Parabolic Trough Collector Efficiency Curve from Separate Measurements of Outdoor Optical Efficiency and Indoor Receiver Heat Loss: Preprint
The overall efficiency of a parabolic trough collector is a function of both the fraction of direct normal radiation absorbed by the receiver (the optical efficiency) and the heat lost to the environment when the receiver is at operating temperature. The overall efficiency can be determined by testing the collector under actual operating conditions or by separately measuring these two components. This paper describes how outdoor measurement of the optical efficiency is combined with laboratory measurements of receiver heat loss to obtain an overall efficiency curve. Further, it presents a new way to plot efficiency that is more robust over a range of receiver operating temperatures.
Kutscher, C.; Burkholder, F.; Stynes, K.
This is the Final Report for two solar cooling projects under this Cooperative Agreement. The first solar cooling project is a roof-integrated solar cooling and heating system, called the Power Roof{trademark}, which began operation in Raleigh, North Carolina in late July 2002. This system provides 176 kW (50 ton) of solar-driven space cooling using a unique nonimaging concentrating solar collector. The measured performance of the system during its first months of operation is reported here, along with a description of the design and operation of this system. The second solar cooling system, with a 20-ton capacity, is being retrofit to a commercial office building in Charleston, South Carolina but has not yet been completed.
Randy C. Gee
Cedarville Elementary & High School Space Heating Low Temperature
Cedarville Elementary & High School Space Heating Low Temperature Cedarville Elementary & High School Space Heating Low Temperature Geothermal Facility Jump to: navigation, search Name Cedarville Elementary & High School Space Heating Low Temperature Geothermal Facility Facility Cedarville Elementary & High School Sector Geothermal energy Type Space Heating Location Cedarville, California Coordinates 41.5290606°, -120.1732781° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[]}
Cotulla High School Space Heating Low Temperature Geothermal Facility |
Cotulla High School Space Heating Low Temperature Geothermal Facility Cotulla High School Space Heating Low Temperature Geothermal Facility Jump to: navigation, search Name Cotulla High School Space Heating Low Temperature Geothermal Facility Facility Cotulla High School Sector Geothermal energy Type Space Heating Location Cotulla, Texas Coordinates 28.436934°, -99.2350322° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[]}
Henley High School Space Heating Low Temperature Geothermal Facility | Open
Henley High School Space Heating Low Temperature Geothermal Facility Henley High School Space Heating Low Temperature Geothermal Facility Jump to: navigation, search Name Henley High School Space Heating Low Temperature Geothermal Facility Facility Henley High School Sector Geothermal energy Type Space Heating Location Klamath Falls, Oregon Coordinates 42.224867°, -121.7816704° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[]}
Modoc High School Space Heating Low Temperature Geothermal Facility | Open
Modoc High School Space Heating Low Temperature Geothermal Facility Modoc High School Space Heating Low Temperature Geothermal Facility Jump to: navigation, search Name Modoc High School Space Heating Low Temperature Geothermal Facility Facility Modoc High School Sector Geothermal energy Type Space Heating Location Alturas, California Coordinates 41.4871146°, -120.5424555° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[]}
City of High Point Electric - Residential Energy Efficiency Rebate...
of High Point. In order to qualify, the heat pump must be between 1 and 5 tons, have a SEER rating of 14 or more, and be installed by an authorizedlicensed electrical or HVAC...
The effects on system efficiency of excess refrigerant line length are calculated for an idealized residential heating and cooling system. By excess line length is meant refrigerant tubing in excess of the 25 R provided for in standard equipment efficiency test methods. The purpose of the calculation is to provide input for a proposed method for evaluating refrigerant distribution system efficiency. A refrigerant distribution system uses refrigerant (instead of ducts or pipes) to carry heat and/or cooling effect from the equipment to the spaces in the building in which it is used. Such systems would include so-called mini-splits as well as more conventional split systems that for one reason or another have the indoor and outdoor coils separated by more than 25 ft. This report performs first-order calculations of the effects on system efficiency, in both the heating and cooling modes, of pressure drops within the refrigerant lines and of heat transfer between the refrigerant lines and the space surrounding them.
Nanocoatings for High-Efficiency Industrial Hydraulic and Tooling Systems
Industrial manufacturing in the U.S. accounts for roughly one third of the 98 quadrillion Btu total energy consumption. Motor system losses amount to 1.3 quadrillion Btu, which represents the largest proportional loss of any end-use category, while pumps alone represent over 574 trillion BTU (TBTU) of energy loss each year. The efficiency of machines with moving components is a function of the amount of energy lost to heat because of friction between contacting surfaces. The friction between these interfaces also contributes to downtime and the loss of productivity through component wear and subsequent repair. The production of new replacement parts requires additional energy. Among efforts to reduce energy losses, wear-resistant, low-friction coatings on rotating and sliding components offer a promising approach that is fully compatible with existing equipment and processes. In addition to lubrication, one of the most desirable solutions is to apply a protective coating or surface treatment to rotating or sliding components to reduce their friction coefficients, thereby leading to reduced wear. Historically, a number of materials such as diamond-like carbon (DLC), titanium nitride (TiN), titanium aluminum nitride (TiAlN), and tungsten carbide (WC) have been examined as tribological coatings. The primary objective of this project was the development of a variety of thin film nanocoatings, derived from the AlMgB14 system, with a focus on reducing wear and friction in both industrial hydraulics and cutting tool applications. Proof-of-concept studies leading up to this project had shown that the constituent phases, AlMgB14 and TiB2, were capable of producing low-friction coatings by pulsed laser deposition. These coatings combine high hardness with a low friction coefficient, and were shown to substantially reduce wear in laboratory tribology tests. Selection of the two applications was based largely on the concept of improved mechanical interface efficiencies for energy conservation. In mobile hydraulic systems, efficiency gains through low friction would translate into improved fuel economy and fewer greenhouse gas emissions. Stationary hydraulic systems, accordingly, would consume less electrical power. Reduced tooling wear in machining operations would translate to greater operating yields, while lowering the energy consumed during processing. The AlMgB14 nanocoatings technology progressed beyond baseline laboratory tests into measurable energy savings and enhancements to product durability. Three key hydraulic markets were identified over the course of the project that will benefit from implementation: industrial vane pumps, orbiting valve-in-star hydraulic motors, and variable displacement piston pumps. In the vane pump application, the overall product efficiency was improved by as much as 11%. Similar results were observed with the hydraulic motors tested, where efficiency gains of over 10% were noted. For variable displacement piston pumps, overall efficiency was improved by 5%. For cutting tools, the most significant gains in productivity (and, accordingly, the efficiency of the machining process as a whole) were associated with the roughing and finishing of titanium components for aerospace systems. Use of the AlMgB14 nanocoating in customer field tests has shown that the coated tools were able to withstand machining rates as high as 500sfm (limited only by the substrate material), with relatively low flank wear when compared to other industrial offerings. AlMgB14 coated tools exhibited a 60% improvement over similarly applied TiAlN thin films. Furthermore, AlMgB14-based coatings in these particular tests lasted twice as long than their TiAlN counterparts at the 500sfm feed rates. Full implementation of the technology into the industrial hydraulic and cutting tool markets equates to a worldwide energy savings of 46 trillion BTU/year by 2030. U.S.-based GHG emissions associated with the markets identified would fall accordingly, dropping by as much as 50,000 tonnes annually.
Clifton B. Higdon III
"Tuning" microalgae for high photosynthesis efficiency
"Tuning" Microalgae For High Photosynthesis Efficiency "Tuning" Microalgae For High Photosynthesis Efficiency "Tuning" microalgae for high photosynthesis efficiency Los Alamos scientist Richard Sayre and his team of researchers have recently developed more efficient microalgae. March 25, 2013 Shown here is a model for light absorption and use by algae as a function of antenna size. Shown here is a model for light absorption and use by algae as a function of antenna size. The team's work in this area is reported in a paper published in the journal Algal Research. Los Alamos scientist Richard Sayre of Bioenergy and Biome Sciences (B-11) and his team of researchers have recently developed more efficient microalgae. Microalgae have large rates of biomass accumulation due to their high photosynthetic efficiencies. This makes them attractive candidates for
Comments on the use of boiler efficiencies to determine unit heat rate
The expression for boiler efficiency defined in ASME PTC4.1 was developed for evaluating boiler performance, carrying out acceptance tests on boilers and computing the effects of changes in parameters such as fuel characteristics on boiler performance. While satisfactory for applications such as these, this particular definition of boiler efficiency can result in substantial errors when used for computing unit performance. Sample calculations are presented for a 600 MW coal fired unit which show errors in net unit heat rate of 1 to 3 percent due to inconsistent definitions for boiler efficiency.
Levy, E.K.; Sarunac, N. (Lehigh Univ., Bethlehem, PA (USA). Energy Research Center); Leyse, R. (Electric Power Research Inst., Palo Alto, CA (USA))
NREL Documents Efficiency of Mini-Split Heat Pumps (Fact Sheet...
MSHPs for any building and climate. Some conclusions comparing the tested units to high-SEER (Seasonal Energy Efficiency Ratio) staged systems are also provided. Potential Impact...
Advanced Intermediate Heat Transport Loop Design Configurations for Hydrogen Production Using High Temperature Nuclear Reactors
The US Department of Energy is investigating the use of high-temperature nuclear reactors to produce hydrogen using either thermochemical cycles or high-temperature electrolysis. Although the hydrogen production processes are in an early stage of development, coupling either of these processes to the high-temperature reactor requires both efficient heat transfer and adequate separation of the facilities to assure that off-normal events in the production facility do not impact the nuclear power plant. An intermediate heat transport loop will be required to separate the operations and safety functions of the nuclear and hydrogen plants. A next generation high-temperature reactor could be envisioned as a single-purpose facility that produces hydrogen or a dual-purpose facility that produces hydrogen and electricity. Early plants, such as the proposed Next Generation Nuclear Plant (NGNP), may be dual-purpose facilities that demonstrate both hydrogen and efficient electrical generation. Later plants could be single-purpose facilities. At this stage of development, both single- and dual-purpose facilities need to be understood. A number of possible configurations for a system that transfers heat between the nuclear reactor and the hydrogen and/or electrical generation plants were identified. These configurations included both direct and indirect cycles for the production of electricity. Both helium and liquid salts were considered as the working fluid in the intermediate heat transport loop. Methods were developed to perform thermal-hydraulic evaluations and cycle-efficiency evaluations of the different configurations and coolants. The thermal-hydraulic evaluations estimated the sizes of various components in the intermediate heat transport loop for the different configurations. The relative sizes of components provide a relative indication of the capital cost associated with the various configurations. Estimates of the overall cycle efficiency of the various configurations were also determined. The evaluations determined which configurations and coolants are the most promising from thermal-hydraulic and efficiency points of view.
Chang Oh; Cliff Davis; Rober Barner; Paul Pickard
Development and Evaluation of Brazed Joints for a Plate Microchnanel Heat Exchanger.
??A brazing method is developed for high efficiency microchannel heat plate heat exchangers for waste heat recovery. Prototype elements for these heat exchangers are fabricated� (more)
Craymer, Kenneth L.
Playing Hot and Cold: How Can Russian Heat Policy Find Its Way Toward Energy Efficiency?
The Russian district heating has a large energy-saving potential, and, therefore, need for investments. The scale of needed investments is significant: the government estimates that 70 percent of the district heating infrastructure needs replacement or maintenance, a reflection of decades of under investment. Government budgets will be unable to cover them, and iInvolvingement ofthe private industry will be critical to attracting the necessary investementis necessary. For private parties to invest in district heating facilities across Russia, and not only in pockets of already successful enterprises, regulators have to develop a comprehensive policy that works district heating systems under various conditionscost-reflective tariffs, metering, incentives for efficiency and social support for the neediest (instead of subsidies for all).
Roshchanka, Volha; Evans, Meredydd
Hydraulic transmissivity and heat exchange efficiency of open fractures: a model based on lowpass filtered apertures
Natural open joints in rocks commonly present multi-scale self-affine apertures. This geometrical complexity affects fluid transport and heat exchange between the flow- ing fluid and the surrounding rock. In particular, long range correlations of self-affine apertures induce strong channeling of the flow which influences both mass and heat advection. A key question is to find a geometrical model of the complex aperture that describes at best the macroscopic properties (hydraulic conductivity, heat exchange) with the smallest number of parameters. Solving numerically the Stokes and heat equa- tions with a lubrication approximation, we show that a low pass filtering of the aperture geometry provides efficient estimates of the effective hydraulic and thermal properties (apertures). A detailed study of the influence of the bandwidth of the lowpass filtering on these transport properties is also performed. For instance, keeping the information of amplitude only of the largest Fourier length scales allows us to rea...
Neuville, Am�lie; Schmittbuhl, Jean; 10.1111/j.1365-246X.2011.05126.x
Very High Efficiency Reactor (VHER) Concepts for Electrical Power Generation and Hydrogen Production
The goal of the Very High Efficiency Reactor study was to develop and analyze concepts for the next generation of nuclear power reactors. The next generation power reactor should be cost effective compared to current power generation plant, passively safe, and proliferation-resistant. High-temperature reactor systems allow higher electrical generating efficiencies and high-temperature process heat applications, such as thermo-chemical hydrogen production. The study focused on three concepts; one using molten salt coolant with a prismatic fuel-element geometry, the other two using high-pressure helium coolant with a prismatic fuel-element geometry and a fuel-pebble element design. Peak operating temperatures, passive-safety, decay heat removal, criticality, burnup, reactivity coefficients, and material issues were analyzed to determine the technical feasibility of each concept.
High efficiency carbonate fuel cell/turbine hybrid power cycles
Carbonate fuel cells developed in commercial 2.85 MW size, have an efficiency of 57.9%. Studies of higher efficiency hybrid power cycles were conducted to identify an economically competitive system and an efficiency over 65%. A hybrid power cycle was identified that includes a direct carbonate fuel cell, a gas turbine, and a steam cycle, which generates power at a LHV efficiency over 70%; it is called a Tandem Technology Cycle (TTC). In a TTC operating on natural gas fuel, 95% of the fuel is mixed with recycled fuel cell anode exhaust, providing water for reforming the fuel, and flows to a direct carbonate fuel cell system which generates 72% of the power. The portion of fuel cell anode exhaust not recycled, is burned and heat is transferred to compressed air from a gas turbine, heating it to 1800 F. The stream is then heated to 2000 F in gas turbine burner and expands through the turbine generating 13% of the power. Half the gas turbine exhaust flows to anode exhaust burner and the rest flows to the fuel cell cathodes providing the O2 and CO2 needed in the electrochemical reaction. Studies of the TTC for 200 and 20 MW size plants quantified performance, emissions and cost-of-electricity, and compared the TTC to gas turbine combined cycles. A 200-MW TTC plant has an efficiency of 72.6%; estimated cost of electricity is 45.8 mills/kWhr. A 20-MW TTC plant has an efficiency of 65.2% and a cost of electricity of 50 mills/kWhr.
Steinfeld, G.
High-frequency plasma-heating apparatus
An array of adjacent wave guides feed high-frequency energy into a vacuum chamber in which a toroidal plasma is confined by a magnetic field, the wave guide array being located between two toroidal current windings. Waves are excited in the wave guide at a frequency substantially equal to the lower frequency hybrid wave of the plasma and a substantially equal phase shift is provided from one guide to the next between the waves therein. For plasmas of low peripheral density gradient, the guides are excited in the TE.sub.01 mode and the output electric field is parallel to the direction of the toroidal magnetic field. For exciting waves in plasmas of high peripheral density gradient, the guides are excited in the TM.sub.01 mode and the magnetic field at the wave guide outlets is parallel to the direction of the toroidal magnetic field. The wave excited at the outlet of the wave guide array is a progressive wave propagating in the direction opposite to that of the toroidal current and is, therefore, not absorbed by so-called "runaway" electrons.
Brambilla, Marco (St. Egreve, FR); Lallia, Pascal (Grenoble, FR)
Highly efficient solar collector including means for preventing cover plate fluid condensation
A solar energy collector of low cost and high thermal efficiency is disclosed having a heat trap produced by zigzagging a thin strip of polyethylene terephthalate between opposite sides of the trap while wrapping the strip about rows of dowels positioned at opposite sides of the frame of the solar collector. A window of soda lime glass filters uv radiation to inhibit discoloration of the plastic heat trap walls. An absorber plate having fluid pipes therein is positioned underneath the heat trap and a first layer of fiberglass, and a second layer of polyurethane foam are positioned below the absorber plate. The fiberglass layer prevents overheating of the polyurethane foam layer to in turn inhibit the formation of toxic fluids, which may condense upon the underside of the window to reduce the efficiency of the collector.
Root, E.F.; Kunica, S.; Simmons, H.M.
High heat flux engineering in solar energy applications
Solar thermal energy systems can produce heat fluxes in excess of 10,000 kW/m{sup 2}. This paper provides an introduction to the solar concentrators that produce high heat flux, the receivers that convert the flux into usable thermal energy, and the instrumentation systems used to measure flux in the solar environment. References are incorporated to direct the reader to detailed technical information.
Cameron, C.P.
Compact and highly efficient laser pump cavity
A new, compact, side-pumped laser pump cavity design which uses non-conventional optics for injection of laser-diode light into a laser pump chamber includes a plurality of elongated light concentration channels. In one embodiment, the light concentration channels are compound parabolic concentrators (CPC) which have very small exit apertures so that light will not escape from the pumping chamber and will be multiply reflected through the laser rod. This new design effectively traps the pump radiation inside the pump chamber that encloses the laser rod. It enables more uniform laser pumping and highly effective recycle of pump radiation, leading to significantly improved laser performance. This new design also effectively widens the acceptable radiation wavelength of the diodes, resulting in a more reliable laser performance with lower cost.
Chang, Jim J. (Dublin, CA); Bass, Isaac L. (Castro Valley, CA); Zapata, Luis E. (Livermore, CA)
Chang, J.J.; Bass, I.L.; Zapata, L.E.
High Efficiency, Ultra-Low Emission, Integrated Process Heater System
The team of TIAX LLC, ExxonMobil Research and Engineering Company, and Callidus Technologies, LLC conducted a six-year program to develop an ultra-low emission process heater burner and an advanced high efficiency heater design. This project addresses the critical need of process heater operators for reliable, economical emission reduction technologies to comply with stringent emission regulations, and for heater design alternatives that reduce process heater energy requirements without significant cost increase. The key project targets were NOx emissions of 10 ppm (@ 3% O2), and a heater thermal efficiency of 95 percent. The ultra low NOx burner was developed through a series of pilot-scale and field tests combined with computational fluid dynamic modeling to arrive at simultaneous low emissions and suitable flame shape and stability. Pilot scale tests were run at TIAX, at the 2 MMBtu/hr scale, and at Callidus at 8 MMBtu/hr. The full scale burner was installed on a 14 burner atmospheric pipestill furnace at an ExxonMobil refinery. A variety of burner configurations, gas tips and flame stabilizers were tested to determine the lowest emissions with acceptable flame shape and stability. The resulting NOx emissions were 22 ppm on average. Starting in 2001, Callidus commercialized the original ultra low NOx burner and made subsequent design improvements in a series of commercial burners evolving from the original concept and/or development. Emissions in the field with the ultra low-NOx burner over a broad spectrum of heater applications have varied from 5 ppm to 30 ppm depending on heater geometry, heater service, fuel and firing capacity. To date, 1550 of the original burners, and 2500 of subsequent generation burners have been sold by Callidus. The advanced heater design was developed by parametric evaluations of a variety of furnace and combustion air preheater configurations and technologies for enhancing convective and radiative heat transfer. The design evolution relied heavily on computational fluid dynamic predictions of design alternatives. The final design features modular separate radiant cells, each with one and two-side fired vertical tubes. The convection section configuration is vertical tube banks enclosed in the radiant channels. Commercial modular plate air preheaters are used. The predicted performance for the integrated advanced heater and Callidus burner is 95 percent efficiency with 9 ppm NOx emissions firing natural gas, and 12 ppm firing refinery gas. The total erected cost is less than a conventional heater with combustion air preheat.
Mason, Howard; Boral, Anindya; Chhotray, San; Martin, Matthew
Compressor performance at high suction temperatures with application to solar heat pump
As part of the study of Solar Assisted Heat Pump (SAHP) Systems, the performance of the heat pump itself and its components under conditions attendant to series solar input to the evaporator is being investigated at Brookhaven National Laboratory (BNL). Particular emphasis has been placed on the details of the compressor performance, since in order to properly exploit the thermodynamic potential of high solar input temperatures (40 to 100/sup 0/F), the compressor must operate efficiently over a wide range of (saturated) suction temperatures most of which are well above those for which present compressors are designed. A systematic series of experiments is being conducted at evaporating temperatures in the range from 45 to 100/sup 0/F using a Solar Heat Pump Simulator and a specially designed Laboratory Model Heat Pump assembled from off-the-shelf components. Two reciprocating compressors have been tested thus far - an open type driven by a 2-speed motor and a hermetic 2-speed, the multi-speed feature providing capacity control, which is a virtual necessity for effective use of solar source. Thorough and highly accurate instrumentation is used in the simulator and in the heat pump refrigeration loop. The results to date of the compressor aspects of the solar heat pump experiments at BNL are described, and the general application of heat pumps and their compressors to use with solar input are discussed.
Kush, E A
Highly Energy Efficient Wall Systems Research Project | Department of
Highly Energy Efficient Wall Systems Highly Energy Efficient Wall Systems Research Project Highly Energy Efficient Wall Systems Research Project The Department of Energy is currently conducting research into highly energy efficient wall systems. Walls with high R-values are better insulators, and their development can help buildings come closer to having zero net energy consumption. Project Description This project seeks to develop a commercially viable wall system up to R-40 through integration of vacuum technology with the exterior insulated façade system (EIFS). Dow Corning will develop a wall system configuration of expanded polystyrene vacuum isolation panels that can be specified for R-values of 20, 30, and 40. This project also aims to develop a unitized protection system of vacuum isolation panels and to validate current code
Department of Energy Lauds Highly Efficient Industrial Technology |
Lauds Highly Efficient Industrial Technology Lauds Highly Efficient Industrial Technology Department of Energy Lauds Highly Efficient Industrial Technology November 30, 2007 - 4:45pm Addthis DOE Celebrates One-Year Anniversary of Operation of the Energy Efficient "Super Boiler" WASHINGTON, DC - Representing important technology transfer from Department of Energy (DOE) labs to the marketplace, DOE today announced the successful one-year operation of the first generation "Super Boiler," which can deliver 94 percent thermal efficiency, while producing fewer emissions than conventional boiler technologies. By 2020, this technology could save more than 185 trillion British Thermal Units (Btus) of energy - equivalent to the natural gas consumed by more than two million households. The
Department of Energy Lauds Highly Efficient Industrial Technology Department of Energy Lauds Highly Efficient Industrial Technology Department of Energy Lauds Highly Efficient Industrial Technology November 30, 2007 - 4:45pm Addthis DOE Celebrates One-Year Anniversary of Operation of the Energy Efficient "Super Boiler" WASHINGTON, DC - Representing important technology transfer from Department of Energy (DOE) labs to the marketplace, DOE today announced the successful one-year operation of the first generation "Super Boiler," which can deliver 94 percent thermal efficiency, while producing fewer emissions than conventional boiler technologies. By 2020, this technology could save more than 185 trillion British Thermal Units (Btus) of energy - equivalent to the natural gas consumed by more than two million households. The
Energy Efficiency Indicators for High Electric-Load Buildings
Energy Efficiency Indicators for High Electric-Load Buildings Energy Efficiency Indicators for High Electric-Load Buildings Speaker(s): Bernard Aebischer Date: February 6, 2003 - 12:00pm Location: Bldg. 90 Seminar Host/Point of Contact: Kristina LaCommare Energy per unit of floor area is not an adequate indictor for energy efficiency in high electric-load buildings. For two activities, restaurants and computer centres, alternative indicators for energy efficiency are discussed. Prerequisites in order to be able to use these indicators in energy efficiency programmes are discussed. The opportunity of an internationally coordinated research activity is also presented. Since 1999, Dr. Bernard Aebischer has served as a senior scientist at CEPE (Centre for Energy Policy and Economics) of the Swiss Federal Institutes of
Improving efficiency of high-concentrator photovoltaics by cooling with
Improving efficiency of high-concentrator photovoltaics by cooling with Improving efficiency of high-concentrator photovoltaics by cooling with two-phase forced convection Title Improving efficiency of high-concentrator photovoltaics by cooling with two-phase forced convection Publication Type Journal Article Year of Publication 2010 Authors Ho, Tony, Samuel S. Mao, and Ralph Greif Journal International Journal of Energy Research Volume 34 Start Page 1257 Issue 14 Pagination 1257-1271 Date Published 11/2010 Keywords high-concentrator photovoltaic efficiency, two-phase flow cooling applications Abstract The potential of increasing high-concentrator photovoltaic cell efficiency by cooling with two-phase flow is analyzed. The governing energy equations were used to predict cell temperature distributions and cell efficiencies for a photovoltaic cell under 100 suns' concentration. Several design conditions were taken into consideration in the analysis, including cooling channel height, working fluid type (between water and R134a), working fluid inlet temperature, pressure, and mass flow rate. It was observed that the dominant parameter for increasing cell efficiency was the working fluid saturation temperature, which itself is affected by a number of the aforementioned design parameters. The results show R134a at low inlet pressures to be highly effective in this two-phase cooling design.
Ongoing Commissioning of a high efficiency supermarket with a ground coupled carbon dioxide refrigeration plant
A significant reduction in the energy consumption and greenhouse gas emissions of supermarkets can be reached by the combination of several innovative components and the continuous optimization of their operation. A German food retail chain developed a new supermarket concept combining several innovative solutions for the refrigeration, lighting and heating/ventilation with the goal to reduce the energy consumption by about 30% compared to a standard subsidiary. A highly insulated building envelope, the use of daylight and covered refrigeration units contribute jointly to reach the goals. The key component of the concept is a carbon dioxide refrigeration plant with waste heat recovery. To reduce the efficiency losses in supercritical operation, carbon dioxide is cooled through a borehole heat exchanger using the ground as a heat sink. In the paper the design concept, the results of simulation studies and of the first monitoring year are presented and discussed.
Rehault, N.; Kalz, D.
Calculation of heating values for the high flux isotope reactor
Calculating the amount of energy released by a fission reaction (fission Q value) and the heating rate distribution in a nuclear reactor is an important part of the safety analysis. However, these calculations can become very complex. One of the codes that can be used for this type of analyses is the Monte Carlo transport code MCNP5. Currently it is impossible to calculate the Q value and heating rate disposition for delayed beta and delayed gamma particles directly from MCNP5. The purpose of this paper is to outline a rigorous method for indirectly calculating the Q values and heating rates in the High Flux Isotope Reactor (HFIR), based on previous similar studies carried out for very high-temperature reactor configurations. This method has been applied in this study to calculate heating rates for the beginning of cycle (BOC) and end-of-cycle (EOC) states of HFIR. In addition, the BOC results obtained for HFIR are compared with corresponding results for the Advanced Test Reactor. The fission Q value for HFIR was calculated as 200.2 MeV for the BOC and 201.3 MeV for the EOC. It was also determined that 95.1% and 95.4% of the heat was deposited within the HFIR fuel plates for the BOC and EOC models, respectively. This methodology can also be used for heating rate calculations for HFIR experiments. (authors)
Peterson, J.; Ilas, G. [Oak Ridge National Laboratory, 1 Bethel Valley Road, Oak Ridge, TN 37831-6172 (United States)
Calculation of Heating Values for the High Flux Isotope Reactor
Calculating the amount of energy released by a fission reaction (fission Q value) and the heating rate distribution in a nuclear reactor is an important part of the safety analysis. However, these calculations can become very complex. One of the codes that can be used for this type of analyses is the Monte Carlo transport code MCNP5. Currently it is impossible to calculate the Q value and heating rate disposition for delayed beta and delayed gamma particles directly from MCNP5. The purpose of this paper is to outline a rigorous method for indirectly calculating the Q values and heating rates in the High Flux Isotope Reactor (HFIR), based on previous similar studies carried out for very high-temperature reactor configurations. This method has been applied in this study to calculate heating rates for the beginning of cycle (BOC) and end-of-cycle (EOC) states of HFIR. In addition, the BOC results obtained for HFIR are compared with corresponding results for the Advanced Test Reactor. The fission Q value for HFIR was calculated as 200.2 MeV for the BOC and 201.3 MeV for the EOC. It was also determined that 95.1% and 95.4% of the heat was deposited within the HFIR fuel plates for the BOC and EOC models, respectively. This methodology can also be used for heating rate calculations for HFIR experiments.
Peterson, Joshua L [ORNL; Ilas, Germina [ORNL
High frequency parametric wave phenomena and plasma heating: a review
A survey of parametric instabilities in plasma, and associated particle heating, is presented. A brief summary of linear theory is given. The physical mechanism of decay instability, the purely growing mode (oscillating two-stream instability) and soliton and density cavity formation is presented. Effects of density gradients are discussed. Possible nonlinear saturation mechanisms are pointed out. Experimental evidence for the existence of parametric instabilities in both unmagnetized and magnetized plasmas is reviewed in some detail. Experimental observation of plasma heating associated with the presence of parametric instabilities is demonstrated by a number of examples. Possible application of these phenomena to heating of pellets by lasers and heating of magnetically confined fusion plasmas by high power microwave sources is discussed. (auth)
Porkolab, M.
NGNP/HTE full-power operation at reduced high-temperature heat exchanger temperatures.
Operation of the Next Generation Nuclear Plant (NGNP) with reduced reactor outlet temperature at full power was investigated for the High Temperature Electrolysis (HTE) hydrogen-production application. The foremost challenge for operation at design temperature is achieving an acceptably long service life for heat exchangers. In both the Intermediate Heat Exchanger (IHX) and the Process Heat Exchanger (PHX) (referred to collectively as high temperature heat exchangers) a pressure differential of several MPa exists with temperatures at or above 850 C. Thermal creep of the heat exchanger channel wall may severely limit heat exchanger life depending on the alloy selected. This report investigates plant performance with IHX temperatures reduced by lowering reactor outlet temperature. The objective is to lower the temperature in heat transfer channels to the point where existing materials can meet the 40 year lifetime needed for this component. A conservative estimate for this temperature is believed to be about 700 C. The reactor outlet temperature was reduced from 850 C to 700 C while maintaining reactor power at 600 MWt and high pressure compressor outlet at 7 MPa. We included a previously reported design option for reducing temperature at the PHX. Heat exchanger lengths were adjusted to reflect the change in performance resulting from coolant property changes and from resizing related to operating-point change. Turbomachine parameters were also optimized for the new operating condition. An integrated optimization of the complete system including heat transfer equipment was not performed. It is estimated, however, that by performing a pinch analysis the combined plant efficiency can be increased from 35.5 percent obtained in this report to a value between 38.5 and 40.1 percent. Then after normalizing for a more than three percent decrease in commodities inventory compared to the reference plant, the commodities-normalized efficiency lies between 40.0 and 41.3. This compares with a value of 43.9 for the reference plant. This latter plant has a reactor outlet temperature of 850 C and the two high temperature heat exchangers. The reduction in reactor outlet temperature from 850 C to 700 C reduces the tritium permeability rate in the IHX metal by a factor of three and thermal creep by five orders of magnitude. The design option for reducing PHX temperature from 800 C to 200 C reduces the permeability there by three orders of magnitude. In that design option this heat exchanger is the single 'choke-point' for tritium migration from the nuclear to the chemical plant.
VIlim, R.; Nuclear Engineering Division
III-V High-Efficiency Multijunction Photovoltaics (Fact Sheet)
Capabilities fact sheet that includes scope, core competencies and capabilities, and contact/web information for III-V High-Efficiency Multijunction Photovoltaics at the National Center for Photovoltaics.
Durable and Highly Efficient Energy-harvesting Electrochromic ...
The resulting device performed three states: solar cell, transparent, and dark, and ... Anatase Nanostructures for High Efficiency Photocatalysis Application ... EBSD Study of Electromigration Damage in Idealized SnAgCu 305 Interconnects.
Energy Efficiency Indicators for High Electric-Load Buildings Speaker(s): Bernard Aebischer Date: February 6, 2003 - 12:00pm Location: Bldg. 90 Seminar HostPoint of Contact:...
Conversion efficiency, scaling and global optimization of high harmonic generation
Closed form expressions for the high harmonic generation (HHG) conversion efficiency in the plateau and cut-off region are derived showing agreement with previous observations. Application of these results to optimal ...
Falcao-Filho, Edilson L.
Highly efficient blue polyfluorene-based polymer light-emitting...
of Physics Volume 42 Pagination 5 Abstract A highly efficient blue polymer light-emitting diode based on poly(9,9-di(2-(2-(2-methoxy-ethoxy)ethoxy)ethyl)fluorenyl-2,7-diyl)...
Phase II Final Project Report SBIR Project: "A High Efficiency PV to Hydrogen Energy System"
The innovative research conducted for this project contributed greatly to the understanding of generating low-cost hydrogen from solar energy. The project�s research identified two highly leveraging and complementary pathways. The first pathway is to dramatically increase the efficiency of converting sunlight into electricity. Improving solar electric conversion efficiency directly increases hydrogen production. This project produced a world record efficiency for silicon solar cells and contributed to another world record efficiency for a solar concentrator module using multijunction solar cells. The project�s literature review identified a second pathway in which wasted heat from the solar concentration process augments the electrolysis process generating hydrogen. One way to do this is to use a �heat mirror� that reflects the heat-producing infrared and transmits the visible spectrum to the solar cells; this also increases solar cell conversion efficiency. An economic analysis of this concept confirms that, if long-term concentrator photovoltaic (CPV) and solid-oxide electrolyzer cost goals can be achieved, hydrogen will be produced from solar energy cheaper than the cost of gasoline. The potential public benefits from this project are significant. The project has identified a potential energy source for the nation�s future electricity and transportation needs that is entirely �home grown� and carbon free. As CPV enter the nation�s utility markets, the opportunity for this approach to be successful is greatly increased. Amonix strongly recommends further exploration of this project�s findings.
Slade, A; Turner, J; Stone, K; McConnell, R
ECUT energy data reference series: high-temperature materials for advanced heat engines
Information that describes the use of high-temperature materials in advanced heat engines for ground transportation applications is summarized. Applications discussed are: automobiles, light trucks, and medium and heavy trucks. The information provided on each of these modes includes descriptions of the average conversion efficiency of the engine, the capital stock, the amount of energy used, and the activity level as measured in ton-miles.
Abarcar, R.B.; Hane, G.J.; Johnson, D.R.
High Performance Trays and Heat Exchangers in Heat Pumped Distillation Columns
Vapor recompression of distillation columns overheads, followed by subsequent condensation in the reboiler results in substantial operating cost savings compared to conventional steam driven reboiler systems. The use of high performance heat exchangers and distillation trays permits additional energy savings by lower reboiler temperature differences, and reduced reflux requirements for a fixed column height, due to closer tray spacings. This paper surveys the heat pump systems currently in operation using high performance UCC MD trays and High Flux tubing. Design considerations for high or low pressure level towers, with single or dual stage compression equipment are discussed, along with the various control methods. Factors affecting startup, part load, and off design operation of the equipment are also reviewed.
Wisz, M. W.; Antonelli, R.; Ragi, E. G.
Test and Evaluation of a High Efficiency Residential Fuel Cell System
A confluence of industry drivers, including the availability of low-cost natural gas, is creating new market opportunities for natural gas-based distributed generation. Solid oxide fuel cell systems (SOFC) are a potentially attractive option because of their high electrical efficiency (50�60% lower heating value (LHV)). This report documents two years of testing and evaluation of a 1.5 kW SOFC residential system provided by Ceramics Fuel Cell Limited. Tests were conducted in collaboration with ...
Coal plasticity at high heating rates and temperatures
The broad objective of this project is to obtain improved, quantitative understanding of the transient plasticity of bituminous coals under high heating rates and other reaction and pretreatment conditions of scientific and practical interest. To these ends the research plan is to measure the softening and resolidification behavior of two US bituminous coals with a rapid-heating, fast response, high-temperature coal plastometer, previously developed in this laboratory. Specific measurements planned for the project include determinations of apparent viscosity, softening temperature, plastic period, and resolidificationtime for molten coal: (1) as a function of independent variations in coal type, heating rate, final temperature, gaseous atmosphere (inert, 0{sub 2} or H{sub 2}), and shear rate; and (2) in exploratory runs where coal is pretreated (preoxidation, pyridine extraction, metaplast cracking agents), before heating. The intra-coal inventory and molecular weight distribution of pyridine extractables will also be measured using a rapid quenching, electrical screen heater coal pyrolysis reactor. The yield of extractables is representative of the intra-coal inventory of plasticing agent (metaplast) remaining after quenching. Coal plasticity kinetics will then be mathematically modeled from metaplast generation and depletion rates, via a correlation between the viscosity of a suspension and the concentration of deformable medium (here metaplast) in that suspension. Work during this reporting period has been concerned with re-commissioning the rapid heating rate plastometer apparatus.
Darivakis, G.S.; Peters, W.A.; Howard, J.B.
Heat exchangers for high-temperature thermodynamic cycles
The special requirements of heat exchangers for high temperature thermodynamic cycles are outlined and discussed with particular emphasis on cost and thermal stress problems. Typical approaches that have been taken to a comprehensive solution intended to meet all of the many boundary conditions are then considered by examining seven typical designs including liquid-to-liquid heat exchangers for nuclear plants, a heater for a closed cycle gas turbine coupled to a fluidized bed coal combustion chamber, steam generators for nuclear plants, a fossil fuel-fired potassium boiler, and a potassium condenser-steam generator. (auth)
Fraas, A.P.
High average power CW FELs (Free Electron Laser) for application to plasma heating: Designs and experiments
A short period wiggler (period {approximately} 1 cm), sheet beam FEL has been proposed as a low-cost source of high average power (1 MW) millimeter-wave radiation for plasma heating and space-based radar applications. Recent calculation and experiments have confirmed the feasibility of this concept in such critical areas as rf wall heating, intercepted beam ( body'') current, and high voltage (0.5 - 1 MV) sheet beam generation and propagation. Results of preliminary low-gain sheet beam FEL oscillator experiments using a field emission diode and pulse line accelerator have verified that lasing occurs at the predicted FEL frequency. Measured start oscillation currents also appear consistent with theoretical estimates. Finally, we consider the possibilities of using a short-period, superconducting planar wiggler for improved beam confinement, as well as access to the high gain, strong pump Compton regime with its potential for highly efficient FEL operation.
Booske, J.H.; Granatstein, V.L.; Radack, D.J.; Antonsen, T.M. Jr.; Bidwell, S.; Carmel, Y.; Destler, W.W.; Latham, P.E.; Levush, B.; Mayergoyz, I.D.; Zhang, Z.X. (Maryland Univ., College Park, MD (USA). Lab. for Plasma Research); Freund, H.P. (Science Applications International Corp., McLean, VA (USA))
Principles of energy efficiency in high performance computing
High Performance Computing (HPC) is a key technology for modern researchers enabling scientific advances through simulation where experiments are either technically impossible or financially not feasible to conduct and theory is not applicable. However, ... Keywords: HPC, PUE, energy efficiency, high performance computing, power usage effectiveness
Axel Auweter; Arndt Bode; Matthias Brehm; Herbert Huber; Dieter Kranzlm�ller
ENTRY LOBBY ENERGY EFFICIENCY Clerestory windows provide natural day-lighting.· Exterior roof SUSTAINABILITY FEATURES #12;ADMINISTRATION ENERGY EFFICIENCY High performance window glazing· minimizes heat gain. Skylights provide natural day-lighting.· High-efficiency lighting reduces energy· costs and heat gain
Escher, Christine
High-efficiency solar cells using HEM silicon
Developments in Heat Exchanger Method (HEM) technology for production of multicrystalline silicon ingot production have led to growth of larger ingots (55 cm square cross section) with lower costs and reliability in production. A single reusable crucible has been used to produce 18 multicrystalline 33 cm square cross section 40 kg ingots, and capability to produce 44 cm ingots has been demonstrated. Large area solar cells of 16.3% (42 cm{sup 2}) and 15.3% (100 cm{sup 2}) efficiency have been produced without optimization of the material production and the solar cell processing.
Khattak, C.P.; Schmid, F. [Crystal Systems, Inc., Salem, MA (United States); Schubert, W.K. [Sandia National Labs., Albuquerque, NM (United States)
High efficiency shale oil recovery. Final report, January 1, 1992--June 30, 1993
The Adams Counter-current shale oil recovery process is an improved retorting technology enabling highly efficient oil recovery from oil shale. The high efficiency results primarily from the following facts: it (1) recovers the ash heat to preheat the feed ore; (2) burns and uses the coke energy and (3) operates without using hot ash recycling as a heat carrier. This latter feature is doubly important, contributing to high oil yield and to the generation of highly reactive coke which can be burned below 1000{degree}F, avoiding the endothermal calcination of the mineral carbonates and helping to clean the ash of contaminants. This project demonstrates that oil shale can be retorted under the specified conditions and achieve the objectives of very high efficiency. The project accomplished the following: 51 quartz sand rotary kiln runs provided significant engineering data. A heat transfer value of 107 Btu/hr/ft{sup 2}/{degree}F was obtained at optimum RPM; eight oil shale samples were obtained and preliminary shakedown runs were made. Five of the samples were selected for kiln processing and twelve pyrolysis runs were made on the five different oil shales;average off recovery was 109% of Fisher Assay; retorted residue from all five samples was oxidized at approximately 1000{degree}F. The ash from these runs was oxidized to varying extents, depending on the oil shale and oxidizing temperatures. While 1000{degree}F is adequately hot to provide process heat from coke combustion for these ores, some Eastern oil shales, without mineral carbonates, may be oxidized at higher temperatures, perhaps 100--300 degrees hotter, to obtain a more complete oxidation and utilization of the coke.
Remote high-temperature insulatorless heat-flux gauge
A remote optical heat-flux gauge for use in extremely high temperature environments is described. This application is possible because of the use of thermographic phosphors as the sensing media, and the omission of the need for an intervening layer of insulator between phosphor layers. The gauge has no electrical leads, but is interrogated with ultraviolet or laser light. The luminescence emitted by the two phosphor layers, which is indicative of the temperature of the layers, is collected and analyzed in order to determine the heat flux incident on the surface being investigated. The two layers of thermographic phosphor must be of different materials to assure that the spectral lines collected will be distinguishable. Spatial heat-flux measurements can be made by scanning the light across the surface of the gauge.
Noel, Bruce W. (Espanola, NM)
A remote optical heat-flux gauge for use in extremely high temperature environments is described. This application is possible because of the use of thermographic phosphors as the sensing media, and the omission of the need for an intervening layer of insulator between phosphor layers. The gauge has no electrical leads, but is interrogated with ultraviolet or laser light. The luminescence emitted by the two phosphor layers, which is indicative of the temperature of the layers, is collected and analyzed in order to determine the heat flux incident on the surface being investigated. The two layers of thermographic phosphor must be of different materials to assure that the spectral lines collected will be distinguishable. Spatial heat-flux measurements can be made by scanning the light across the surface of the gauge. 3 figures.
Noel, B.W.
Remote high temperature insulatorless heat-flux gauge
A remote optical heat-flux gauge for use in high temperature environments. This application is possible because of the use of thermographic phosphors as the sensing media, and the omission of the need for an intervening layer of insulator between phosphor layers. The gauge has no electrical leads, but is interrogated with ultraviolet light. The luminescence emitted by the two thermographic-phosphor layers, which is indicative of the temperature of the layers, is collected and analyzed in order to determine the heat flux incident on the surface being investigated. The two layers of thermographic phosphor must be of different materials to assure that the spectral lines collected will be distinguishable. Spatial heat flux measurements can be made by scanning the light across the surface of the gauge.
High-temperature process heat applications with an HTGR
An 842-MW(t) HTGR-process heat (HTGR-PH) design and several synfuels and energy transport processes to which it could be coupled are described. As in other HTGR designs, the HTGR-PH has its entire primary coolant system contained in a prestressed concrete reactor vessel (PCRV) which provides the necessary biological shielding and pressure containment. The high-temperature nuclear thermal energy is transported to the externally located process plant by a secondary helium transport loop. With a capability to produce hot helium in the secondary loop at 800/sup 0/C (1472/sup 0/F) with current designs and 900/sup 0/C (1652/sup 0/F) with advanced designs, a large number of process heat applications are potentially available. Studies have been performed for coal liquefaction and gasification using nuclear heat.
Quade, R.N.; Vrable, D.L.
High Efficiency Solar Power via Separated Photo and Voltaic Pathways
This project demonstrates a novel nanostructured solar cell architecture capable of achieving high efficiency levels that is relatively simple and inexpensive to manufacture. The high efficiency will be achieved by the novel structure that separates the path of the photons from the path of the generated charge carriers. In this way, the photon path can be long for maximum light absorption, while the path for carriers can be short for maximum electronic energy harvesting. The combination of maximum light absorption coupled with maximum carrier harvesting is the basis for the expected high efficiency. The project will develop high efficiency solar cell prototypes utilizing this unique nanostructured architecture. The project addresses the fundamental limitation inherent in all current solar cell designs, and which opens a pathway to development for high efficiency solar cells at low cost. Realizing this goal will result in a levelized cost of electricity in the range of 10�/kWh, which would achieve the long-sought goal of making photovoltaic electricity cost competitive with fossil-fuel generated electricity without any governmental subsidies. This breakthrough would spur the already rapid growth in the photovoltaic industry to an explosive pace, with significant, widespread benefit to the national economy and the nation�s energy security. The initial target of the program is to develop single-junction solar cells using ultrathin amorphous silicon with the performance approaching that of single crystal silicon cells.
Michael J. Naughton
This Low Friction (High Efficiency Roller Bearing) Engine (LFE) report presents the work done by The Timken Company to conduct a technology demonstration of the benefits of replacing hydrodynamic bearings with roller bearings in the crankshaft and camshaft assemblies of an internal combustion engine for the purpose of collecting data sufficient to prove merit. The engines in the present study have been more extensively converted to roller bearings than any previous studies (40 needle roller bearings per engine) to gain understanding of the full potential of application of bearing technology. The project plan called for comparative testing of a production vehicle which was already respected for having demonstrated low engine friction levels with a rollerized version of that engine. Testing was to include industry standard tests for friction, emissions and fuel efficiency conducted on instrumented dynamometers. Additional tests for fuel efficiency, cold start resistance and other measures of performance were to be made in the actual vehicle. Comparative measurements of noise, vibration and harshness (NVH), were planned, although any work to mitigate the suspected higher NVH level in the rollerized engine was beyond the scope of this project. Timken selected the Toyota Avalon with a 3.5L V-6 engine as the test vehicle. In an attempt to minimize cost and fabrication time, a �made-from� approach was proposed in which as many parts as possible would be used or modified from production parts to create the rollerized engine. Timken commissioned its test partner, FEV Engine Technology, to do a feasibility study in which they confirmed that using such an approach was possible to meet the required dimensional restrictions and tolerances. In designing the roller bearing systems for the crank and cam trains, Timken utilized as many production engine parts as possible. The crankshafts were produced from production line forgings, which use Timken steel, modified with special machining and heat treatment. Timken designed and manufactured all of the roller bearing related components such as the thrust bearing package. The production connecting rods and camshafts could not be used for the roller bearing engine, so new ones were produced according to the team�s designs using Timken steel. The remaining miscellaneous components were designed and procured by FEV. Timken prepared a display version of the crankshaft portion of the production engine without connecting rods which could be driven by a motor through a cogged-belt and electrically actuated clutch arrangement. A modified version was also made in which the engine was outfitted with roller bearings on the main bearing positions. Preliminary tests showed that the rollerized engine was running with 1/3 less friction than the standard display engine. Additional friction testing and noise characterization was cut short because of shipping damage to the rollerized engine display and because of other project priorities. The team did successfully demonstrate the ability to package roller bearings satisfactorily in numerous locations in a typical automotive engine. The scope of this project did not include durability demonstration and that subject would have to be addressed in any follow-on work. In the actual test phase, the rollerized engine did show significantly less friction in motored dynamometer tests compared to its production equivalent. The 5-10% improvement measured in this study was about half that seen in other studies. However, the fired test results did not show a reduction in friction which did not match prior experience or expectations. Subsequent teardown and inspection of the rollerized engine revealed potential sources of excessive friction in the experimental application. These features would be eliminated in a design not based on modification of production parts. The team is confident (based on experience) that friction reduction would be realized with proper modifications.
Kolarik, Robert V. II; Shattuck, Charles W.; Copper, Anthony P.
Demonstration and Performance Monitoring of Foundation Heat Exchangers in Low Load, High Performance Research Homes
Demonstration and Performance Monitoring of Foundation Heat Exchangers (FHX) in Low Load, High Performance Research Homes Piljae Im, Ph.D. Oak Ridge National Laboratory Building America Technical Update Meeting April 29 - 30, Denver, Colorado ACKNOWLEDGEMENT * This project was sponsored by the Building Technologies Office of the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy and the Tennessee Valley Authority (TVA). Managed by UT-Battelle for the U.S. Department of Energy 2 PRESENTATION OVERVIEW * INTRODUCTION * FIELD TEST OF THE FOUNDATION HEAT EXCHANGER (FHX) CONCEPT * FOUNDATION HEAT EXCHANGER PERFORMANCE MEASUREMENTS * ADDITIONAL FINDINGS AND COST COMPARISON * SUMMARY Managed by UT-Battelle for the U.S. Department of Energy
High Energy Density Thermal Batteries: Thermoelectric Reactors for Efficient Automotive Thermal Storage
HEATS Project: Sheetak is developing a new HVAC system to store the energy required for heating and cooling in EVs. This system will replace the traditional refrigerant-based vapor compressors and inefficient heaters used in today�s EVs with efficient, light, and rechargeable hot-and-cold thermal batteries. The high energy density thermal battery�which does not use any hazardous substances�can be recharged by an integrated solid-state thermoelectric energy converter while the vehicle is parked and its electrical battery is being charged. Sheetak�s converters can also run on the electric battery if needed and provide the required cooling and heating to the passengers�eliminating the space constraint and reducing the weight of EVs that use more traditional compressors and heaters.
High Efficiency and High Rate Deposited Amorphous Silicon-Based Solar Cells
of a triple cell showing 10.7% stable efficiency. Figure 4-1 Schematic diagram of the Hot Wire CVD deposition. Task 7: High-rate deposition of a-Si based solar cells We have conducted extensive research using a hot1 High Efficiency and High Rate Deposited Amorphous Silicon-Based Solar Cells PHASE I Annual
Deng, Xunming
SunShot Initiative: High-Efficiency Thermal Energy Storage System for CSP
High-Efficiency Thermal Energy Storage System for CSP High-Efficiency Thermal Energy Storage System for CSP ANL logo Photo of a black and white porous material magnified 50 times by a microscope. Microstructure of the highly thermal conductive foam that will be used for the prototype TES system. Image from ANL Argonne National Laboratory and project partner Ohio Aerospace Institute, under the National Laboratory R&D competitive funding opportunity, will design, develop, and test a prototype high-temperature and high-efficiency thermal energy storage (TES) system with rapid charging and discharging times. By increasing the efficiency of TES systems, this project aims to lower the capital costs of concentrating solar power (CSP) systems. Approach The research team is developing and evaluating a novel approach for TES at temperatures greater than 700˚C for CSP systems. The approach uses high thermal conductivity and high-porosity graphite foams infiltrated with a phase change material (PCM) to provide TES in the form of latent heat.
High efficiency III-nitride light-emitting diodes
Tailored doping of barrier layers enables balancing of the radiative recombination among the multiple-quantum-wells in III-Nitride light-emitting diodes. This tailored doping enables more symmetric carrier transport and uniform carrier distribution which help to reduce electron leakage and thus reduce the efficiency droop in high-power III-Nitride LEDs. Mitigation of the efficiency droop in III-Nitride LEDs may enable the pervasive market penetration of solid-state-lighting technologies in high-power lighting and illumination.
Crawford, Mary; Koleske, Daniel; Cho, Jaehee; Zhu, Di; Noemaun, Ahmed; Schubert, Martin F; Schubert, E. Fred
Heat pipe array heat exchanger
A heat pipe arrangement for exchanging heat between two different temperature fluids. The heat pipe arrangement is in a ounterflow relationship to increase the efficiency of the coupling of the heat from a heat source to a heat sink.
Reimann, Robert C. (Lafayette, NY)
Low Cost, High Efficiency, High Pressure Hydrogen Storage
A technical and design evaluation was carried out to meet DOE hydrogen fuel targets for 2010. These targets consisted of a system gravimetric capacity of 2.0 kWh/kg, a system volumetric capacity of 1.5 kWh/L and a system cost of $4/kWh. In compressed hydrogen storage systems, the vast majority of the weight and volume is associated with the hydrogen storage tank. In order to meet gravimetric targets for compressed hydrogen tanks, 10,000 psi carbon resin composites were used to provide the high strength required as well as low weight. For the 10,000 psi tanks, carbon fiber is the largest portion of their cost. Quantum Technologies is a tier one hydrogen system supplier for automotive companies around the world. Over the course of the program Quantum focused on development of technology to allow the compressed hydrogen storage tank to meet DOE goals. At the start of the program in 2004 Quantum was supplying systems with a specific energy of 1.1-1.6 kWh/kg, a volumetric capacity of 1.3 kWh/L and a cost of $73/kWh. Based on the inequities between DOE targets and Quantum�s then current capabilities, focus was placed first on cost reduction and second on weight reduction. Both of these were to be accomplished without reduction of the fuel system�s performance or reliability. Three distinct areas were investigated; optimization of composite structures, development of �smart tanks� that could monitor health of tank thus allowing for lower design safety factor, and the development of �Cool Fuel� technology to allow higher density gas to be stored, thus allowing smaller/lower pressure tanks that would hold the required fuel supply. The second phase of the project deals with three additional distinct tasks focusing on composite structure optimization, liner optimization, and metal.
Mark Leavitt
High Performance Healthcare Buildings: A Roadmap to Improved Energy Efficiency
technologies such as ground source heat pumps. Advisors Highrecovery chillers, ground-source heat pumps (newer designs
Singer, Brett C.
Heat-pipe development for high-temperature recuperator application
Heat pipes have been developed for operation in oxidizing atmospheres at temperatures above 1100/sup 0/K. The heat pipes comprise a metallic liner and wick structure with a protective outer shell of an oxidation resistant material. The working fluids used in the heat pipes are alkali metals. A number of configurations have been evaluated, ranging from pipes using a metallic inner liner of a chemically vapor deposited (CVD) refractory metal applied to ceramic tubing, to one utilizing ferrous materials with an outer layer of a developed oxide. A promising intermediate configuration consisting of free-standing refractory tubing covered with a layered structure of fine grain, equi-axed CVD silicon carbide has also been evaluated. The test heat pipe was fabricated using low-carbon, arc-cast molybdenum tubing and a wick composed of 150 mesh molybdenum screen. Hafnium gettering was used with sodium working fluid. Assembly of the pipe was by electron beam welding. Following closure and capping of the fill tube the assembly was operated in a vacuum for several hours prior to the chemical vapor deposition of the exterior ceramic coating. After coating, the pipe was operated in air and in combustion gases for performance evaluation. The use of iron-chromium-aluminum alloys as container materials for operating in high temperature oxidizing and sulfiding gas streams has been investigated. Alloys of this type develop heavy, protective oxide surface layers when exposed to high temperature oxidizing atmospheres, and are commonly used in electrical heating elements because of their exceptional oxidation resistance.
Merrigan, M.; Dunwoody, W.; Lundberg, L.
A method to determine stratification efficiency of thermal energy storage processes independently from storage heat losses
A new method for the calculation of a stratification efficiency of thermal energy storages based on the second law of thermodynamics is presented. The biasing influence of heat losses is studied theoretically and experimentally. Theoretically, it does not make a difference if the stratification efficiency is calculated based on entropy balances or based on exergy balances. In practice, however, exergy balances are less affected by measurement uncertainties, whereas entropy balances can not be recommended if measurement uncertainties are not corrected in a way that the energy balance of the storage process is in agreement with the first law of thermodynamics. A comparison of the stratification efficiencies obtained from experimental results of charging, standby, and discharging processes gives meaningful insights into the different mixing behaviors of a storage tank that is charged and discharged directly, and a tank-in-tank system whose outer tank is charged and the inner tank is discharged thereafter. The new method has a great potential for the comparison of the stratification efficiencies of thermal energy storages and storage components such as stratifying devices. (author)
Haller, Michel Y.; Streicher, Wolfgang [Institute of Thermal Engineering, Graz University of Technology, Inffeldgasse 25/B, 8010 Graz (Austria); Yazdanshenas, Eshagh; Andersen, Elsa; Furbo, Simon [Department of Civil Engineering, Technical University of Denmark, Brovej, Building 118, DK-2800, Kgs. Lyngby (Denmark); Bales, Chris [Solar Energy Research Center SERC, Hoegskolan Dalarna, 781 88 Borlaenge (Sweden)
Energy Efficiency Loan Program (Pennsylvania) | Open Energy Informatio...
Summary The Keystone HELP Energy Efficiency Loan Program is designed to help homeowners improve energy efficiency with special financing for high-efficiency heating, air...
Bandgap Engineering in High-Efficiency Multijunction Concentrator Cells
This paper discusses semiconductor device research paths under investigation with the aim of reaching the milestone efficiency of 40%. A cost analysis shows that achieving very high cell efficiencies is crucial for the realization of cost-effective photovoltaics, because of the strongly leveraging effect of efficiency on module packaging and balance-of systems costs. Lattice-matched (LM) GaInP/ GaInAs/ Ge 3-junction cells have achieved the highest independently confirmed efficiency at 175 suns, 25?C, of 37.3% under the standard AM1.5D, low-AOD terrestrial spectrum. Lattice-mismatched, or metamorphic (MM), materials offer still higher potential efficiencies, if the crystal quality can be maintained. Theoretical efficiencies well over 50% are possible for a MM GaInP/ 1.17-eV GaInAs/ Ge 3-junction cell limited by radiative recombination at 500 suns. The bandgap - open circuit voltage offset, (Eg/q) - Voc, is used as a valuable theoretical and experimental tool to characterize multijunction cells with subcell bandgaps ranging from 0.7 to 2.1 eV. Experimental results are presented for prototype 6-junction cells employing an active {approx}1.1-eV dilute nitride GaInNAs subcell, with active-area efficiency greater than 23% and over 5.3 V open-circuit voltage under the 1-sun AM0 space spectrum. Such cell designs have theoretical efficiencies under the terrestrial spectrum at 500 suns concentration exceeding 55% efficiency, even for lattice-matched designs.
King, R. R.; Sherif, R. A.; Kinsey, G. S.; Kurtz, S.; Fetzer, C. M.; Edmondson, K. M.; Law, D. C.; Cotal, H. L.; Krut, D. D.; Ermer, J. H.; Karam, N. H.
Comparison of energy efficiency between variable refrigerant flow systems and ground source heat pump systems
Performance of ground source heat pump system in a near-zerosimulation tool for ground- source heat pump system designflow systems and ground source heat pump systems Abstract
Hong, Tainzhen
Properties of High Efficiency CIGS Thin Film Solar Cells
We present experimental results in three areas. Solar cells with an efficiency of 19% have been fabricated with an absorber bandgap in the range of 1.1-1.2 eV. Properties of solar cells fabricated with and without an undoped ZnO layer were compared. The data show that high efficiency cells can be fabricated without using the high-resistivity or undoped ZnO layer. Properties of CIGS solar cells were fabricated from thin absorbers (1 {micro}m) deposited by the three-stage process and simultaneous co-deposition of all the elements. In both cases, solar cells with efficiencies of 16%-17% are obtained.
Ramanathan, K.; Keane, J.; Noufi, R.
Desalination of seawater using a high-efficiency jet ejector
The ability to produce potable water economically is the primary focus of seawater desalination research. There are numerous methods to desalinate water, including reverse osmosis, multi-stage flash distillation, and multi-effect evaporation. These methods cost more than potable water produced from natural resources; hence an attempt is made in this research project to produce potable water using a modified high-efficiency jet ejector in vapor-compression distillation. The greater efficiency of the jet ejector is achieved by properly mixing propelled and motive streams. From experiments conducted using air, the pressure rise across the jet ejector is better in case of one or two mixing vanes and the highest back pressure (pinch valve closed 83.33%). At other pinch valve closings, the air velocity through the jet ejector was high, so the extra surface area from the mixing vanes caused excessive friction and lowered the efficiency.
Vishwanathappa, Manohar D.
Area-efficient high-throughput MAP decoder architectures
Iterative decoders such as turbo decoders have become integral components of modern broadband communication systems because of their ability to provide substantial coding gains. A key computational kernel in iterative decoders is the maximum a posteriori ... Keywords: area efficient, block-interleaved pipelining, high throughput, parallel processing, pipeline, symbol-based decoding, turbo decoder, turbo equalizer
Seok-Jun Lee; Naresh R. Shanbhag; Andrew C. Singer
Motor voltage high harmonics influence to efficient energy usage
Analysis of the effect of non-sinusoidal voltages on the three-phase induction motor is presented in the paper. When the induction motors are supplied by a rectangular shape of the voltage inverter with high levels of harmonic voltage (Uh,i ... Keywords: energy efficiency, harmonics, induction motor, non-sinusoidal voltage, power losses
Miloje M. Kostic; Branka B. Kostic
Basic studies of 3-5 high efficiency cell components
This project's objective is to improve our understanding of the generation, recombination, and transport of carriers within III-V homo- and heterostructures. The research itself consists of fabricating and characterizing solar cell building blocks'' such as junctions and heterojunctions as well as basic measurements of material parameters. A significant effort is also being directed at characterizing loss mechanisms in high-quality, III-V solar cells fabricated in industrial research laboratories throughout the United States. The project's goal is to use our understanding of the device physics of high-efficiency cell components to maximize cell efficiency. A related goal is the demonstration of new cell structures fabricated by molecular beam epitaxy (MBE). The development of measurement techniques and characterization methodologies is also a project objective. This report describes our progress during the fifth and final year of the project. During the past five years, we've teamed a great deal about heavy doping effects in p[sup +] and n[sup +] GaAs and have explored their implications for solar cells. We have developed an understanding of the dominant recombination losses in present-day, high-efficiency cells. We've learned to appreciated the importance of recombination at the perimeter of the cell and have developed techniques for chemically passivating such edges. Finally, we've demonstrated that films grown by molecular beam epitaxy are suitable for high-efficiency cell research.
Lundstrom, M.S.; Melloch, M.R.; Pierret, R.F.; Carpenter, M.S.; Chuang, H.L.; Dodd, P.E.; Keshavarzi, A.; Klausmeier-Brown, M.E.; Lush, G.B.; Stellwag, T.B. (Purdue Univ., Lafayette, IN (United States))
Second Generation Biofuels: High-Efficiency Microalgae for Biodiesel Production
it as chemical energy. This presents a route for renewable and carbon-neutral fuel production. However, currentSecond Generation Biofuels: High-Efficiency Microalgae for Biodiesel Production Peer M. Schenk that are not only renewable, but also capable of sequestering atmospheric CO2. Currently, nearly all renewable
Kudela, Raphael M.
High-quantum efficiency, long-lived luminescing refractory oxides
A crystal having a high-quantum efficiency and a long period of luminescence is formed of an oxide selected from the group consisting of magnesium oxide and calcium oxide and possessing a concentration ratio of H.sup.- ions to F centers in the range of about 0.05 to about 10.
Chen, Yok (Oak Ridge, TN); Gonzalez, Roberto (Knoxville, TN); Summers, Geoffrey P. (Stillwater, OK)
Technology Development Roadmap for the Advanced High Temperature Reactor Secondary Heat Exchanger
This Technology Development Roadmap (TDRM) presents the path forward for deploying large-scale molten salt secondary heat exchangers (MS-SHX) and recognizing the benefits of using molten salt as the heat transport medium for advanced high temperature reactors (AHTR). This TDRM will aid in the development and selection of the required heat exchanger for: power production (the first anticipated process heat application), hydrogen production, steam methane reforming, methanol to gasoline production, or ammonia production. This TDRM (a) establishes the current state of molten salt SHX technology readiness, (b) defines a path forward that systematically and effectively tests this technology to overcome areas of uncertainty, (c) demonstrates the achievement of an appropriate level of maturity prior to construction and plant operation, and (d) identifies issues and prioritizes future work for maturing the state of SHX technology. This study discusses the results of a preliminary design analysis of the SHX and explains the evaluation and selection methodology. An important engineering challenge will be to prevent the molten salt from freezing during normal and off-normal operations because of its high melting temperature (390�C for KF ZrF4). The efficient transfer of energy for industrial applications depends on the ability to incorporate cost-effective heat exchangers between the nuclear heat transport system and industrial process heat transport system. The need for efficiency, compactness, and safety challenge the capabilities of existing heat exchanger technology. The description of potential heat exchanger configurations or designs (such as printed circuit, spiral or helical coiled, ceramic, plate and fin, and plate type) were covered in an earlier report (Sabharwall et al. 2011). Significant future work, much of which is suggested in this report, is needed before the benefits and full potential of the AHTR can be realized. The execution of this TDRM will focuses research efforts on the near-term qualification, selection, or maturation strategy as detailed in this report. Development of the integration methodology feasibility study, along with research and development (R&D) needs, are ongoing tasks that will be covered in the future reports as work progresses. Section 2 briefly presents the integration of AHTR technology with conventional chemical industrial processes., See Idaho National Laboratory (INL) TEV-1160 (2011) for further details
P. Sabharwall; M. McCllar; A. Siahpush; D. Clark; M. Patterson; J. Collins
Research on stable, high-efficiency amorphous silicon multijunction modules
This report describes research to improve the understanding of amorphous silicon alloys and other relevant non-semiconductor materials for use in high-efficiency, large-area multijunction modules. The research produced an average subcell initial efficiency of 8.8% over a 1-ft{sup 2} area using same-band-gap, dual-junction cells deposited over a ZnO/AlSi back reflector. An initial efficiency of 9.6% was achieved using a ZnO/Ag back reflector over smaller substrates. A sputtering machine will be built to deposit a ZnO/Ag back reflector over a 1-ft{sup 2} area so that a higher efficiency can also be obtained on larger substrates. Calculations have been performed to optimize the grid pattern, bus bars, and cell interconnects on modules. With our present state of technology, we expect a difference of about 6% between the aperture-area and active-area efficiencies of modules. Preliminary experiments show a difference of about 8%. We can now predict the performance of single-junction cells after long-term light exposure at 50{degree}C by exposing cells to short-term intense light at different temperatures. We find that single-junction cells deposited on a ZnO/Ag back reflector show the highest stabilized efficiency when the thickness of the intrinsic layers is about 2000 {angstrom}. 8 refs.
Guha, S. (United Solar Systems Corp., Troy, MI (United States))
Toward high-energy-density, high-efficiency, and moderate-temperature chip-scale thermophotovoltaics
The challenging problem of ultra-high-energy-density, high-efficiency, and small-scale portable power generation is addressed here using a distinctive thermophotovoltaic energy conversion mechanism and chip-based system ...
Pilawa-Podgurski, R. C. N.
The origins of the hot solar corona and the supersonically expanding solar wind are still the subject of debate. A key obstacle in the way of producing realistic simulations of the Sun�heliosphere system is the lack of a physically motivated way of specifying the coronal heating rate. Recent one-dimensional models have been found to reproduce many observed features of the solar wind by assuming the energy comes from Alfv�n waves that are partially reflected, then dissipated by magnetohydrodynamic turbulence. However, the nonlocal physics of wave reflection has made it difficult to apply these processes to more sophisticated (three-dimensional) models. This paper presents a set of robust approximations to the solutions of the linear Alfv�n wave reflection equations. A key ingredient of the turbulent heating rate is the ratio of inward-to-outward wave power, and the approximations developed here allow this to be written explicitly in terms of local plasma properties at any given location. The coronal heating also depends on the frequency spectrum of Alfv�n waves in the open-field corona, which has not yet been measured directly. A modelbased assumption is used here for the spectrum, but the results of future measurements can be incorporated easily. The resulting expression for the coronal heating rate is self-contained, computationally efficient, and applicable directly to global models of the corona and heliosphere. This paper tests and validates the approximations by comparing the results to exact solutions of the wave transport equations in several cases relevant to the fast and slow solar wind. Key words: interplanetary medium � magnetohydrodynamics (MHD) � solar wind � Sun: corona � turbulence � waves Online-only material: tar file of source code 1.
Steven R. Cranmer
Efficiency Efficiency Opportunities in Federal High Performance Computing Data Centers Prepared for the U.S. Department of Energy Federal Energy Management Program By Lawrence Berkeley National Laboratory Rod Mahdavi, P.E. LEED A.P. September 2013 2 Contacts Rod Mahdavi, P.E. LEED AP Lawrence Berkeley National Laboratory (510) 495-2259 email@example.com For more information on FEMP: Will Lintner, P.E. Federal Energy Management Program U.S. Department of Energy (202) 586-3120 email@example.com 3 Contents Executive Summary .................................................................................................... 6 Overview .................................................................................................................... 7
High-efficiency multidetector system for tumor scanning
A high-efficiency detector system developed especially for medical imaging has three specially cut Ge(Li) coaxial detectors (total volume 249 cm$sup 3$). At 122 keV, the peak efficiency is 93 percent of that of a 7.6 x 7.6 cm NaI (Tl) detector. Degradation of the paralleled energy resolution is avoided and resolution is improved by 35 percent over that of conventional output-summing techniques by gating the detector outputs. In effect this multiplexes them to a single line output. (auth)
Kirby, J.A.; Phelps, P.L.; Armantrout, G.A.; Sawyer, D.; Beck, R.N.
High Efficiency LED Lamp for Solid-State Lighting
This report contains a summary of technical achievements during a three-year project to demonstrate high efficiency, solid-state lamps based on gallium nitride/silicon carbide light-emitting diodes. Novel chip designs and fabrication processes are described for a new type of nitride light-emitting diode with the potential for very high efficiency. This work resulted in the demonstration of blue light-emitting diodes in the one watt class that achieved up to 495 mW of light output at 350 mA drive current, corresponding to quantum and wall plug efficiencies of 51% and 45%, respectively. When combined with a phosphor in Cree's 7090 XLamp package, these advanced blue-emitting devices resulted in white light-emitting diodes whose efficacy exceeded 85 lumens per watt. In addition, up to 1040 lumens at greater than 85 lumens per watt was achieved by combining multiple devices to make a compact white lamp module with high optical efficiency.
James Ibbetson
A Perspective on the Future of High Efficiency Engines
New fuel economy standards and emissions regulations are accelerating the development of new engine technologies, sensors, and on-board computing. These developments will enable unprecedented engine control, which will in turn enable real-world implementations of low temperature combustion, high-speed controls, and other high efficiency engine technologies. With this expanded flexibility in engine design and control, the challenge will now be the exponential increase in the design and calibration space and the need for the development of new simulations, optimization methods, and self-learning control methodologies. This manuscript provides historical and future perspectives on the opportunities and challenges of this unparalleled technology growth on the next generation of high efficiency engines.
Wagner, Robert M [ORNL; Curran, Scott [ORNL; Green Jr, Johney Boyd [ORNL
High Quality Down Lighting Luminaire with 73% Overall System Efficiency
This report summarizes work to develop a high flux, high efficiency LED-based downlight at OSRAM SYLVANIA under US Department of Energy contract DE-FC26-08NT01582. A new high power LED and electronic driver were developed for these downlights. The LED achieved 100 lumens per watt efficacy and 1700 lumen flux output at a correlated color temperature of 3500K. The driver had 90% electrical conversion efficiency while maintaining excellent power quality with power factor >0.99, and total harmonic distortion LED and driver were shown to exceed the project targets for steady-state luminous efficacy and flux of 70 lumens per watt and 1300 lumens, respectively. Compared to similar existing downlights using compact fluorescent or LED sources, these downlights had much higher efficacy at nearly the same luminous flux.
Robert Harrison; Steven C. Allen; Joseph Bernier; Robert Harrison
This report summarizes work to develop a high flux, high efficiency LED-based downlight at OSRAM SYLVANIA under US Department of Energy contract DE-FC26-08NT01582. A new high power LED and electronic driver were developed for these downlights. The LED achieved 100 lumens per watt efficacy and 1700 lumen flux output at a correlated color temperature of 3500K. The driver had 90% electrical conversion efficiency while maintaining excellent power quality with power factor >0.99, and total harmonic distortion <10%. Two styles of downlights using the LED and driver were shown to exceed the project targets for steady-state luminous efficacy and flux of 70 lumens per watt and 1300 lumens, respectively. Compared to similar existing downlights using compact fluorescent or LED sources, these downlights had much higher efficacy at nearly the same luminous flux.
Materials development and field demonstration of high-recycled-content concrete for energy-efficient building construction
The project developed high-recycled-content concrete material with balanced structural and thermal attributes for use in energy-efficient building construction. Recycled plastics, tire, wool, steel and concrete were used as replacement for coarse aggregates in concrete and masonry production. With recycled materials the specific heat and thermal conductivity of concrete could be tailored to enhance the energy-efficiency of concrete buildings. A comprehensive field project was implemented which confirmed the benefits of high-recycled-content concrete for energy-efficient building construction.
Ostowari, Ken; Nosson, Ali
Development and Demonstration of a New Generation High Efficiency 10kW Stationary Fuel Cell System
The overall project objective is to develop and demonstrate a polymer electrolyte membrane fuel cell combined heat and power (PEMFC CHP) system that provides the foundation for commercial, mass produced units which achieve over 40% electrical efficiency (fuel to electric conversion) from 50-100% load, greater than 70% overall efficiency (fuel to electric energy + usable waste heat energy conversion), have the potential to achieve 40,000 hours durability on all major process components, and can be produced in high volumes at under $400/kW (revised to $750/kW per 2011 DOE estimates) capital cost.
Howell, Thomas Russell
Investigating potential efficiency improvement for light-duty transportation applications through simulation of an organic Rankine cycle for waste-heat recovery
Modern diesel engines used in light-duty transportation applications have peak brake thermal efficiencies in the range of 40-42% for high-load operation with substantially lower efficiencies at realistic road-load conditions. Thermodynamic energy and exergy analysis reveals that the largest losses from these engines are due to heat loss and combustion irreversibility. Substantial improvement in overall engine efficiency requires reducing or recovering these losses. Unfortunately, much of the heat transfer either occurs at relatively low temperatures resulting in large entropy generation (such as in the air-charge cooler), is transferred to low-exergy flow streams (such as the oil and engine coolant), or is radiated or convected directly to the environment. While there are significant opportunities for recovery from the exhaust and EGR cooler for heavy-duty applications, the potential benefits of such a strategy for light-duty applications are unknown due to transient operation, low-load operation at typical driving conditions, and the added mass of the system. We have developed an organic Rankine cycle model using GT-Suite to investigate the potential for efficiency improvement through waste-heat recovery from the exhaust and EGR cooler of a light-duty diesel engine. Results from steady-state and drive-cycle simulations are presented, and we discuss strategies to address operational difficulties associated with transient drive cycles and competition between waste-heat recovery systems, turbochargers, aftertreatment devices, and other systems for the limited thermal resources.
Edwards, Kevin Dean [ORNL; Wagner, Robert M [ORNL
High efficiency vapor-fed AMTEC system for direct conversion. Final report
The Alkali Metal Thermal to Electric Converter (AMTEC) is a high temperature, high efficiency system for converting thermal to electrical energy, with no moving parts. It is based on the unique properties of {beta}{double_prime}-alumina solid electrolyte (BASE), which is an excellent conductor of sodium ions, but an extremely poor conductor of electrons. When the inside of the BASE is maintained at a higher temperature and pressure, a concentration gradient is created across the BASE. Electrons and sodium atoms cannot pass through the BASE. However, the sodium atoms are ionized, and the sodium ions move through the BASE to the lower potential (temperature) region. The electrons travel externally to the AMTEC cell, providing power. There are a number of potential advantages to a wick-pumped, vapor-fed AMTEC system when compared with other designs. A wick-pumped system uses capillary forces to passively return liquid to the evaporator, and to distribute the liquid in the evaporator. Since the fluid return is self-regulating, multiple BASE tubes can use a single remote condenser, potentially improving efficiency in advanced AMTEC designs. Since the system is vapor-fed, sodium vapor is supplied at a uniform temperature and flux to the BASE tube, even with non-uniform heat fluxes and temperatures at the evaporator. The primary objective of the Phase 2 program was to develop wick-pumped AMTEC cells. During the program, procedures to fabricate wicks with smaller pore sizes were developed, to allow operation of an AMTEC cell at 800 C. A revised design was made for a High-Temperature, Wick-Fed AMTEC cell. In addition to the smaller wick pore size, several other changes were made to increase the cell efficiency: (1) internal artery return of condensate; (2) high temperature electrical feedthrough; and (3) separate heat pipe for providing heat to the BASE.
Anderson, W.G.; Bland, J.J.
High-efficiency cadmium and zinc-telluride-based thin-film solar cells
This report describes research into polycrystalline CdTe solar cells grown by metal-organic chemical vapor deposition. Efficiencies of {approximately}10% were achieved using both p-i-n and p-n structures. A pre-heat treatment of CdS/SnO{sub 2}/glass substrates at 450{degrees}C in hydrogen atmosphere prior to the CdTe growth was found to be essential for high performance because this heat treatment reduces oxygen-related defects from the CdS surface. However, this treatment also resulted in a Cd-deficient CdS surface, which may in part limit the CdTe cell efficiency to 10% due to Cd vacancy-related interface defects. Preliminary model calculations suggest that removing these states can increase the cell efficiency from 10% to 13.5%. Photon absorption in the CdS film also limits the cell performance, and eliminating this loss mechanism can result in CdTe efficiencies in excess of 18%. Polycrystalline, 1.7-e, CdZnTe films were also grown for tandem-cell applications. CdZnTe/CdS cells processed using the standard CdTe cell fabrication procedure resulted in 4.4% efficiency, high series resistance, and a band-gap shift to 1.55 eV. The formation of Zn-O at and near the CdZnTe surface is the source of high contact resistance. A saturated dichromate each prior to contact deposition was found to solve the contact resistance problem. The CdCl{sub 2} treatment was identified as the cause of the observed band-gap shift due to the preferred formation of ZnCl{sub 2}. 59 refs.
Rohatgi, A.; Sudharsanan, R.; Ringel, S. (Georgia Inst. of Tech., Atlanta, GA (United States))
This report describes the progress made during Phase 1 of research and development program to obtain high-efficiency amorphous silicon alloy multijunction modules. Using a large-area deposition system, double-and triple-junction cells were made on stainless steel substrates of over 1 ft{sup 2} area with Ag and ZnO predeposited back reflector. Modules of over 1 ft{sup 2} were produced with between 9.2% and 9.9 initial aperture-area efficiencies as measured under a USSC Spire solar simulator. Efficiencies as measured under the NREL Spire solar simulator were found to be typically 15% to 18% lower. The causes for this discrepancy are now being investigated. The modules show about 15% degradation after 600 hours of one-sun illumination at 50{degrees}C. To optimize devices for higher stabilized efficiency, a new method was developed by which the performance of single-junction cells after long-term, one-sun exposure at 50{degrees}C can be predicted by exposing cells to short-term intense light at different temperatures. This method is being used to optimize the component cells of the multijunction structure to obtain the highest light-degraded efficiency.
Banerjee, A.; Chen, E.; Clough, R.; Glatfelter, T.; Guha, S.; Hammond, G.; Hopson, M.; Jackett, N.; Lycette, M.; Noch, J.; Palmer, T.; Pawlikiewicz, A.; Rosenstein, I.; Ross, R.; Wolf, D.; Xu, X.; Yang, J.; Younan, K.
High-efficiency solar cell and method for fabrication
A high-efficiency 3- or 4-junction solar cell is disclosed with a theoretical AM0 energy conversion efficiency of about 40%. The solar cell includes p-n junctions formed from indium gallium arsenide nitride (InGaAsN), gallium arsenide (GaAs) and indium gallium aluminum phosphide (InGaAlP) separated by n-p tunnel junctions. An optional germanium (Ge) p-n junction can be formed in the substrate upon which the other p-n junctions are grown. The bandgap energies for each p-n junction are tailored to provide substantially equal short-circuit currents for each p-n junction, thereby eliminating current bottlenecks and improving the overall energy conversion efficiency of the solar cell. Additionally, the use of an InGaAsN p-n junction overcomes super-bandgap energy losses that are present in conventional multi-junction solar cells. A method is also disclosed for fabricating the high-efficiency 3- or 4-junction solar cell by metal-organic chemical vapor deposition (MOCVD).
Hou, Hong Q. (Albuquerque, NM); Reinhardt, Kitt C. (Albuquerque, NM)
A high-efficiency 3- or 4-junction solar cell is disclosed with a theoretical AM0 energy conversion efficiency of about 40%. The solar cell includes p-n junctions formed from indium gallium arsenide nitride (InGaAsN), gallium arsenide (GaAs) and indium gallium aluminum phosphide (InGaAlP) separated by n-p tunnel junctions. An optional germanium (Ge) p-n junction can be formed in the substrate upon which the other p-n junctions are grown. The bandgap energies for each p-n junction are tailored to provide substantially equal short-circuit currents for each p-n junction, thereby eliminating current bottlenecks and improving the overall energy conversion efficiency of the solar cell. Additionally, the use of an InGaAsN p-n junction overcomes super-bandgap energy losses that are present in conventional multi-junction solar cells. A method is also disclosed for fabricating the high-efficiency 3- or 4-junction solar cell by metal-organic chemical vapor deposition (MOCVD). 4 figs.
Hou, H.Q.; Reinhardt, K.C.
Test Program for High Efficiency Gas Turbine Exhaust Diffuser
This research relates to improving the efficiency of flow in a turbine exhaust, and thus, that of the turbine and power plant. The Phase I SBIR project demonstrated the technical viability of �strutlets� to control stalls on a model diffuser strut. Strutlets are a novel flow-improving vane concept intended to improve the efficiency of flow in turbine exhausts. Strutlets can help reduce turbine back pressure, and incrementally improve turbine efficiency, increase power, and reduce greenhouse gas emmission. The long-term goal is a 0.5 percent improvement of each item, averaged over the US gas turbine fleet. The strutlets were tested in a physical scale model of a gas turbine exhaust diffuser. The test flow passage is a straight, annular diffuser with three sets of struts. At the end of Phase 1, the ability of strutlets to keep flow attached to struts was demonstrated, but the strutlet drag was too high for a net efficiency advantage. An independently sponsored followup project did develop a highly-modified low-drag strutlet. In combination with other flow improving vanes, complicance to the stated goals was demonstrated for for simple cycle power plants, and to most of the goals for combined cycle power plants using this particular exhaust geometry. Importantly, low frequency diffuser noise was reduced by 5 dB or more, compared to the baseline. Appolicability to other diffuser geometries is yet to be demonstrated.
Norris, Thomas R.
Integration of High Efficiency Solar Cells on Carriers for Concentrating System Applications .
??High efficiency multi-junction (MJ) solar cells were packaged onto receiver systems. The efficiency change of concentrator cells under continuous high intensity illumination was done. Also,� (more)
Chow, Simon Ka Ming
According to The Hydronics Institute, the surge in gas-fired boiler shipments brought about 3 years ago by high oil prices and the availability of natural gas after years of curtailment has almost competely subsided. Gas prices continue to escalate and the threat of decontrol by 1985 continues. Likewise, the Gas Appliance Manufacturers Association reports that shipments of gas-fired unit heaters, duct furnaces, and wall furnaces have also dropped as homeowners adopt a wait-and-see attitude toward conversion. However, the market for high- and ultra-high-efficiency furnaces appears to hold potential for expansion. Because of the rebounding home market, a steady replacement market, and increased sales for reasons of efficiency, GAMA expects the total (gas, oil, and electric) central furnace market to increase by 16% in 1983.
High Magnetic Field Processing - A Heat-Free Heat Treating Method
The High and Thermal Magnetic Processing/Electro-magnetic Acoustic Transducer (HTMP/EMAT) technology has been shown to be an enabling disruptive materials processing technology, that can achieve significant improvements in microstructure and consequently material performance beyond that achievable through conventional processing, and will lead to the next generation of advanced performance structural and functional materials. HTMP exposure increased the reaction kinetics enabling refinement of microstructural features such as finer martensite lath size, and finer, more copious, homogeneous dispersions of strengthening carbides leading to combined strength and toughness improvements in bainitic steels. When induction heating is applied in a high magnetic field environment, the induction heating coil is configured so that high intensity acoustic/ultrasonic treatment occurs naturally. The configuration results in a highly effective electromagnetic acoustical transducer (EMAT). HTMP combined with applying high-field EMAT, produce a non-contact ultrasonic treatment that can be used to process metal alloys in either the liquid state resulting in significant microstructural changes over conventional processing. Proof-of-principle experiments on cast irons resulted in homogeneous microstructures in small castings along with improved casting surface appearance. The experiment showed that by exposing liquid metal to the non-contact acoustic/ultrasonic processing technology developed using HMFP/EMAT wrought-like microstructures were developed in cast components. This Energy Intensive Processes (EIP) project sponsored by the DOE EERE Advanced Manufacturing Office (AMO) demonstrated the following: (1) The reduction of retained austenite in high carbon/high alloy steels with an ambient temperature HTMP process, replacing either a cryogenic or double tempering thermal process normally employed to accomplish retained austenite transformation. HTMP can be described as a 'heat-free', heat treating technology. Lower residual stresses in HTMP treated materials are anticipated since no thermal strains are involved in inducing the transformation of retained austenite to martensite in high alloy steel. (2) The simultaneous increase of 12% in yield strength and 22% in impact energy in a bainitic alloy using HTMP processing. This is a major breakthrough in materials processing for the next generation of structural materials since conventionally processed materials show a reduction in impact toughness with an increase in yield strength. HTMP is a new paradigm to beneficially increase both yield strength and impact energy absorption simultaneously. (3) HTMP processing refined both the martensite lath population and the carbide dispersion in a bainitic steel alloy during Gausstempering. The refinement was believed to be responsible for the simultaneous increase in strength and toughness. Hence, HTMP significantly impacts nucleation and growth phenomenon. (4) HTMP processing developed comparable ultimate tensile strength and twice the impact energy in a lower cost, lower alloy content ({approx}8% alloy content) steel, compared to highly alloyed, (31% alloy elements involving Ni, Co, and Mo) 250-grade margining steel. Future low-cost HTMP alloys appear viable that will exceed the structural performance of highly alloyed materials that are conventionally processed. This economic benefit will enable U.S. industry to reduce cost (better more competitive worldwide) while maintaining or exceeding current performance. (5) EMAT processed cast iron exhibits significantly higher hardness (by 51% for a 9T condition) than a no-field processed sample. (6) EMAT produced microstructures in cast iron resulted in an unique graphite nodule morphology, a modified pearlite content, and unique carbide types, that formed during solidification and cooling. (7) EMAT processed nanoparticle dispersions in Mg resulted in a very fine, unagglomerated distribution of the nanoparticles in the magnesium matrix. This provides a breakthrough technology to make the next generation of
Ludtka, Gerard Michael [ORNL; Ludtka, Gail Mackiewicz- [ORNL; Wilgen, John B [ORNL; Kenik, Edward A [ORNL; Parish, Chad M [ORNL; Rios, Orlando [ORNL; Rogers, Hiram [ORNL; Manuel, Michele [University of Florida, Gainesville; Kisner, Roger A [ORNL; Watkins, Thomas R [ORNL; Murphy, Bart L [ORNL
High Energy-Efficiency Retrofits to Baltimore's Row Homes
The purpose of the research project is to develop high-perfommnce, energy-eflicient retrofits of existing row homes in Baltimore, Maryland. These efficiency enhancements are to optimize building envelope improvements, mechanical equipment improvements and operational improvements to the highest cost-effective level. Furthermore, this project is to investigate and demonstrate the impact of high-performance energy-efficiency retrofit improvements on row homes in the Historic East area of Baltimore. Three homes awaiting renovation are planned to receive building envelope, mechanical system, and electrical system improvements that will improve their energy petiormance. An incremental additional cost ceiling of $4000 for the energy eftlciency improvements, beyond those normally installed, has been set by the project.
Chalk, J.; Johnson, A.L.; Lipscomb, L.; Wendt, R.
High-Efficiency Solar Cell Concepts: Physics, Materials, and Devices
Over the past three decades, significant progress has been made in the area of high-efficiency multijunction solar cells, with the effort primarily directed at current-matched solar cells in tandem. The key materials issues here have been obtaining semiconductors with the required bandgaps for sequential absorption of light in the solar spectrum and that are lattice matched to readily available substrates. The GaInP/GaAs/Ge cell is a striking example of success achieved in this area. Recently, several new approaches for high-efficiency solar cell design have emerged, that involve novel methods for tailoring alloy bandgaps, as well as alternate technologies for hetero-epitaxy of III-V's on Si. The advantages and difficulties expected to be encountered with each approach will be discussed, addressing both the materials issues and device physics whilst contrasting them with other fourth-generation solar cell concepts.
Mascarenhas, A.; Francoeur, S.; Seong, M. J.; Fluegel, B.; Zhang, Y.; Wanlass, M. W.
Prototyping Energy Efficient Thermo-Magnetic & Induction Hardening for Heat Treat & Net Shape Forming Applications
Within this project, Eaton undertook the task of bringing about significant impact with respect to sustainability. One of the major goals for the Department of Energy is to achieve energy savings with a corresponding reduction in carbon foot print. The use of a coupled induction heat treatment with high magnetic field heat treatment makes possible not only improved performance alloys, but with faster processing times and lower processing energy, as well. With this technology, substitution of lower cost alloys for more exotic alloys became a possibility; microstructure could be tailored for improved magnetic properties or wear resistance or mechanical performance, as needed. A prototype commercial unit has been developed to conduct processing of materials. Testing of this equipment has been conducted and results demonstrate the feasibility for industrial commercialization.
Aquil Ahmad
SunShot Initiative: High Operating Temperature Liquid Metal Heat Transfer
High Operating Temperature Liquid Metal Heat Transfer Fluids High Operating Temperature Liquid Metal Heat Transfer Fluids UCLA logo University of California Berkeley logo Yale logo Four graphics in a grid that represent the sputtering technique being used in this project. Combinatorial screening and high throughput characterization of materials will be used to identify, develop, and demonstrate metal alloys that meet the MURI HOT Fluids targets suitable for CSP applications. The University of California, Los Angeles, the University of California, Berkeley, and Yale University The University of California, Los Angeles (UCLA), along with partners at the University of California, Berkeley, and Yale University, under the 2012 Multidisciplinary University Research Initiative (MURI): High Operating Temperature (HOT) Fluids funding opportunity, is investigating the use of metal alloys as a heat transfer fluid (HTF) in concentrating solar power (CSP) systems operating at temperatures in excess of 800°C. By allowing higher temperature operation, CSP systems can achieve greater efficiencies and thereby reduce the overall cost of electricity production.
Fabrication and Design Aspects of High-Temperature Compact Diffusion Bonded Heat Exchangers
The very high temperature reactor (VHTR), using gas-cooled reactor technology, is one of the six reactor concepts selected by the Generation IV International Forum and is anticipated to be the reactor type for the next generation nuclear plant (NGNP). In this type of reactor with an indirect power cycle system, a high-temperature and high integrity intermediate heat exchanger (IHX) with high effectiveness is required to efficiently transfer the core thermal output to secondary fluid for electricity production, process heat, or hydrogen cogeneration. The current Technology Readiness Level status issued by NGNP to all components associated with the IHX for reactor core outlet temperatures of 750-800oC is 3 on a scale of 1 to 10 with 10 being the most ready. At present, there is no proven high-temperature IHX concept for VHTRs. Amongst the various potential IHX concepts available, diffusion bonded heat exchangers (henceforth called printed circuit heat exchangers, or PCHEs) appear promising for NGNP applications. The design and fabrication of this key component of NGNP is the primary focus of this paper. In the current study, two PCHEs were fabricated using Alloy 617 plates and will be experimentally investigated for their thermal-hydraulic performance in a high-temperature helium test facility (HTHF). The HTHF was primarily designed and constructed to test the thermal-hydraulic performance of PCHEs The test facility is primarily of Alloy 800H construction and is designed to facilitate experiments at temperatures and pressures up to 800oC and 3 MPa, respectively. The PCHE fabrication related processes, i.e., photochemical machining and diffusion bonding are briefly discussed for Alloy 617 plates. Diffusion bonding of Alloy 617 plates with and without a Ni interlayer is discussed. Furthermore, preliminary microstructural and mechanical characterization studies of representative diffusion bonded Alloy 617 specimens are presented.
Mylavarapu, Sai K. [Ohio State University; Sun, Xiaodong [Ohio State University; Christensen, Richard N. [Ohio State University; Glosup, Richard E. [Ohio State University; Unocic, Raymond R [ORNL
Enhancing Condensers for Geothermal Systems: the Effect of High Contact Angles on Dropwise Condensation Heat Transfer
Phase change heat transfer is notorious for increasing the irreversibility of, and therefore decreasing the efficiency of, geothermal power plants. Its significant contribution to the overall irreversibility of the plant makes it the most important source of inefficiency in the process. Recent studies here have shown the promotion of drop wise condensation in the lab by means of increasing the surface energy density of a tube with nanotechnology. The use of nanotechnology has allowed the creation of surface treatments which discourage water from wetting a tube surface during a static test. These surface treatments are unique in that they create high- contact angles on the condensing tube surfaces to promote drop wise condensation.
Kennedy, John M.; Kim, Sunwoo; Kim, Kwang J.
Symmetric quantum dots as efficient sources of highly entangled photons
An ideal source of entangled photon pairs combines the perfect symmetry of an atom with the convenient electrical trigger of light sources based on semiconductor quantum dots. We create a naturally symmetric quantum dot cascade that emits highly entangled photon pairs on demand. Our source consists of strain-free GaAs dots self-assembled on a triangular symmetric (111)A surface. The emitted photons strongly violate Bell's inequality and reveal a fidelity to the Bell state as high as 86 (+-2) % without postselection. This result is an important step towards scalable quantum-communication applications with efficient sources.
T. Kuroda; T. Mano; N. Ha; H. Nakajima; H. Kumano; B. Urbaszek; M. Jo; M. Abbarachi; Y. Sakuma; K. Sakoda; I. Suemune; X. Marie; T. Amand
Design and demonstration of heat pipe cooling for NASP and evaluation of heating methods at high heating rates
An evaluation of two heating methods for demonstration of NASP leading edge heat pipe technology was conducted. The heating methods were and rf induction heated plasma jet and direct rf induction. Tests were conducted to determine coupling from the argon plasma jet on a surface physically similar to a heat pipe. A molybdenum tipped calorimeter was fabricated and installed in an rf induction heated plasma jet for the test. The calorimetric measurements indicated a maximum power coupling of approximately 500 W/cm{sup 2} with the rf plasma jet. The effect of change in gas composition on the heating rate was investigated using helium. An alternative to the plasma heating of a heat pipe tip, an rf concentrator was evaluated for coupling to the hemispherical tip of a heat pipe. A refractory metal heat pipe was designed, fabricated, and tested for the evaluation. The heat pipe was designed for operation at 1400 to 1900 K with power input to 1000 W/cm{sup 2} over a hemispherical nose tip. Power input of 800 W/cm{sup 2} was demonstrated using the rf concentrator. 2 refs., 13 figs.
Merrigan, M.A.; Sena, J.T.
High temperature solid lubricant materials for heavy duty and advanced heat engines
Advanced engine designs incorporate higher mechanical and thermal loading to achieve efficiency improvements. This approach often leads to higher operating temperatures of critical sliding elements (e.g. piston ring/cylinder wall contacts and valve guides) which compromise the use of conventional and even advanced synthetic liquid lubricants. For these applications solid lubricants must be considered. Several novel solid lubricant composites and coatings designated PS/PM200 have been employed to dry and marginally oil lubricated contacts in advanced heat engines. These applications include cylinder kits of heavy duty diesels, and high temperature sterling engines, sidewall seals of rotary engines and various exhaust valve and exhaust component applications. The following paper describes the tribological and thermophysical properties of these tribomaterials and reviews the results of applying them to engine applications. Other potential tribological materials and applications are also discussed with particular emphasis to heavy duty and advanced heat engines.
DellaCorte, C.; Wood, J.C.
technologies include absorption chillers that utilizeinclude use of absorption chillers when heat sources are
RF heating and current drive on NSTX with high
NSTX is a small aspect ratio tokamak (R = 0.85 m, a = 0.65 m). The High Harmonic Fast Wave (HHFW) system is a 30 MHz, 12-element array capable of launching both symmetric and directional wave spectra for plasma heating and non-inductive current drive. It has delivered up to 6 MW for short pulses and has routinely operated at ~3 MW for 100-400 ms pulses. Results include strong, centrally-peaked electron heating in both D and He plasmas for both high and low phase velocity spectra. H-modes were obtained with application of HHFW power alone, with stored energy doubling after the L-H transition. Beta poloidal as large as unity has been obtained with significant fractions (0.4) of bootstrap current. Differences in the loop voltage are observed depending on whether the array is phased to drive current in the co- or counter-current directions. A fast ion tail with energies extending up to 140 keV has been observed when HHFW interacts with 80 keV neutral beams; neutron rate and lost ion measurements, as well as modeling, indicate significant power absorption by the fast ions. Radial rf power deposition and driven current profiles have been calculated with ray tracing and kinetic full-wave codes and compared with measurements.
Ryan, Philip Michael [ORNL; Peng, Yueng Kay Martin [ORNL
In-Plant Testing of High-Efficiency Hydraulic Separators
Hydraulic separators are commonly used for particle size classification and gravity concentration of minerals and coal. Unfortunately, the efficiency of these processes can be quite low due to poor equipment design and variations in feed consistency. To help alleviate these problems, an industry-driven R&D program has been undertaken to develop a new generation of hydraulic separators that are more efficient and less costly to operate and maintain. These units, which are commercially called the CrossFlow separator and HydroFloat separator, have the potential to improve performance (separation efficiency and throughput) and reduce operating costs (power consumption, water and reagent usage). In Phase I of this project, laboratory and pilot-scale test units were evaluated at various industrial sites in both the coal and mineral industries. Based on promising results obtained from Phase I, full-scale prototypes were purchased and installed by a major U.S. phosphate producer and a large eastern U.S. coal company. The test data obtained from these sites demonstrate that significant performance improvements can be realized through the application of these high-efficiency separators.
G. H. Luttrell; R. Q. Honaker; R. C. Bratton; T. C. Westerfield; J. N. Kohmuench
G.H. Luttrell; R.Q. Honaker; R.C. Bratton; T.C. Westerfield; J.N. Kohmuench
Wound tube heat exchanger
What is disclosed is a wound tube heat exchanger in which a plurality of tubes having flattened areas are held contiguous adjacent flattened areas of tubes by a plurality of windings to give a double walled heat exchanger. The plurality of windings serve as a plurality of effective force vectors holding the conduits contiguous heat conducting walls of another conduit and result in highly efficient heat transfer. The resulting heat exchange bundle is economical and can be coiled into the desired shape. Also disclosed are specific embodiments such as the one in which the tubes are expanded against their windings after being coiled to insure highly efficient heat transfer.
Ecker, Amir L. (Duncanville, TX)
BSA 09-27: Synthesis of High-Efficiency Thermoelectric Materials
Thermoelectric materials must exhibit both high electrical conductivity and low thermal conductivity in order to usefully convert heat to electricity ...
Efficiency United (Gas) - Residential Efficiency Program | Department of
Efficiency United (Gas) - Residential Efficiency Program Efficiency United (Gas) - Residential Efficiency Program Efficiency United (Gas) - Residential Efficiency Program < Back Eligibility Low-Income Residential Multi-Family Residential Residential Savings Category Heating & Cooling Commercial Heating & Cooling Heating Home Weatherization Commercial Weatherization Sealing Your Home Appliances & Electronics Construction Design & Remodeling Other Ventilation Manufacturing Water Heating Windows, Doors, & Skylights Maximum Rebate Weatherization Measures: 50% of the cost Windows: $150 Water Heaters/Clothes Washers: 1 Pipe Wrap: Limit of 10 linear ft. Faucet Aerators: 2 High Efficiency Shower Head: 2 Program Info State Michigan Program Type Utility Rebate Program Rebate Amount Boiler: $200 Furnace: $100 - $200
Comparison of energy efficiency between variable refrigeranttheir superior energy efficiency. The variable refrigerantfew studies reporting the energy efficiency of VRF systems
Design of high efficiency blowers for future aerosol applications
High efficiency air blowers to meet future portable aerosol sampling applications were designed, fabricated, and evaluated. A Centrifugal blower was designed to achieve a flow rate of 100 L/min (1.67 x 10^-3 m^3/s) and a pressure rise of WC " 4 (1000 PA). Commercial computational fluid dynamics (CFD) software, FLUENT 6.1.22, was used extensively throughout the entire design cycle. The machine, Reynolds number (Re) , was around 10^5 suggesting a turbulent flow field. Renormalization Group (RNG) �?ºâ�?�?�?µ turbulent model was used for FLUENT simulations. An existing design was scaled down to meet the design needs. Characteristic curves showing static pressure rise as a function of flow rate through the impeller were generated using FLUENT and these were validated through experiments. Experimentally measured efficiency (�?·EXP) for the base-design was around 10%. This was attributed to the low efficiency of the D.C. motor used. CFD simulations, using the �?ºâ�?�?�?µ turbulent model and standard wall function approach, over-predicted the pressure rise values and the percentage error was large. Enhanced wall function under-predicted the pressure rise but gave better agreement (less than 6% error) with experimental results. CFD predicted a blower scaled 70% in planar direction (XZ) and 28% in axial direction (Y) and running at 19200 rpm (email@example.com) as the most appropriate choice. The pressure rise is 1021 Pa at the design flow rate of 100 L/min. FLUENT predicts an efficiency value based on static head (�?·FLU) as 53.3%. Efficiency value based on measured static pressure rise value and the electrical energy input to the motor (�?·EXP) is 27.4%. This is almost a 2X improvement over the value that one gets with the hand held vacuum system blower.
Chadha, Raman
This study confirms the feasibility of a natural gas fueled, 20 MW M-C Power integrated pressurized molten carbonate fuel cell combined in a topping cycle with a gas turbine generator plant. The high efficiency fossil power plant (HEFPP) concept has a 70% efficiency on a LHV basis. The study confirms the HEFPP has a cost advantage on a cost of electricity basis over the gas turbine based combined cycle plants in the 20 MW size range. The study also identifies the areas of further development required for the fuel cell, gas turbine generator, cathode blower, inverter, and power module vessel. The HEFPP concept offers an environmentally friendly power plant with minuscule emission levels when compared with the combined cycle power plant.
J.L. Justice
Heat transfer issues in high-heat-load synchrotron x-ray beams
In this paper, a short description of the synchrotron radiation x-ray sources and the associated power loads is given, followed by a brief description of typical synchrotron components and their heat load. It is emphasized that the design goals for most of these components is to limit (a) temperature, (b) stresses, or (c) strains in the system. Each design calls for a different geometry, material selection, and cooling scheme. Cooling schemes that have been utilized so far are primarily single phase and include simple macrochannel cooling, microchannel cooling, contact cooling, pin-post cooling, porous-flow cooling, jet cooling, etc. Water, liquid metals, and various cryogenic coolants have been used. Because the trend in x-ray beam development is towards brighter (i.e., more powerful) beams and assuming that no radical changes in the design of x-ray generating machines occurs in the next few years, it is fair to state that the utilization of various effective cooling schemes and, in particular, two-phase flow (e.g., subcooled boiling) warrants further investigation. This, however, requires a thorough examination of stability and reliability of two-phase flows for high-heat-flux components operating in ultrahigh vacuum with stringent reliability requirements.
Khounsary, A.M.; Mills, D.M.
The deterioration in heat transfer to fluids at supercritical pressure and high heat fluxes
At slightly supercritical pressure and in the neighborhood of the pseudo-critical temperature (defined as the temperature corresponding to the peak in specific heat at the operating pressure), the heat transfer coefficient ...
Shiralkar, B. S.
Heat pipe technology development for high temperature space radiator applications
Technology requirements for heat pipe radiators, potentially among the lightest weight systems for space power applications, include flexible elements, and improved specific radiator performance(kg/kW). For these applications a flexible heat pipe capable of continuous operation through an angle of 180/sup 0/ has been demonstrated. The effect of bend angle on the heat pipe temperature distribution is reviewed. An analysis of lightweight membrane heat pipe radiators that use surface tension forces for fluid containment has been conducted. The design analysis of these lightweight heat pipes is described and a potential application in heat rejection systems for space nuclear power plants outlined.
Merrigan, M.A.; Keddy, E.S.; Sena, J.T.; Elder, M.G.
High-Temperature Experiments using a Resistively-Heated High-Pressure Membrane Diamond Anvil Cell
A reliable high-performance heating method using resistive heaters and a membrane driven diamond anvil cell (mDAC) is presented. Two micro-heaters are mounted in a mDAC and use electrical power of less than 150 W to achieve sample temperatures up to 1200 K. For temperature measurement we use two K-type thermocouples mounted near the sample. The approach can be used for in-situ Raman spectroscopy and x-ray diffraction at high pressures and temperatures. A W-Re alloy gasket material permits stable operation of mDAC at high temperature. Using this method, we made an isothermal compression at 900 K to pressures in excess of 100 GPa and isobaric heating at 95 GPa to temperatures in excess of 1000 K. As an example, we present high temperature Raman spectroscopy measurements of nitrogen at high pressures.
Jenei, Z; Visbeck, K; Cynn, H; Yoo, C; Evans, W
High Operating Temperature Liquid High Operating Temperature Liquid Metal Heat Transfer Fluids to someone by E-mail Share SunShot Initiative: High Operating Temperature Liquid Metal Heat Transfer Fluids on Facebook Tweet about SunShot Initiative: High Operating Temperature Liquid Metal Heat Transfer Fluids on Twitter Bookmark SunShot Initiative: High Operating Temperature Liquid Metal Heat Transfer Fluids on Google Bookmark SunShot Initiative: High Operating Temperature Liquid Metal Heat Transfer Fluids on Delicious Rank SunShot Initiative: High Operating Temperature Liquid Metal Heat Transfer Fluids on Digg Find More places to share SunShot Initiative: High Operating Temperature Liquid Metal Heat Transfer Fluids on AddThis.com... Concentrating Solar Power Systems Components Competitive Awards
Air flow in a high aspect ratio heat sink
The increasing heat output of modern electronics requires concomitant advances in heat sinking technology: reductions in thermal resistance and required pumping power are necessary. This research covers the development of ...
Allison, Jonathan Michael
A High Efficiency PSOFC/ATS-Gas Turbine Power System
A study is described in which the conceptual design of a hybrid power system integrating a pressurized Siemens Westinghouse solid oxide fuel cell generator and the Mercury{trademark} 50 gas turbine was developed. The Mercury{trademark} 50 was designed by Solar Turbines as part of the US. Department of Energy Advanced Turbine Systems program. The focus of the study was to develop the hybrid power system concept that principally would exhibit an attractively-low cost of electricity (COE). The inherently-high efficiency of the hybrid cycle contributes directly to achieving this objective, and by employing the efficient, power-intensive Mercury{trademark} 50, with its relatively-low installed cost, the higher-cost SOFC generator can be optimally sized such that the minimum-COE objective is achieved. The system cycle is described, major system components are specified, the system installed cost and COE are estimated, and the physical arrangement of the major system components is discussed. Estimates of system power output, efficiency, and emissions at the system design point are also presented. In addition, two bottoming cycle options are described, and estimates of their effects on overall-system performance, cost, and COE are provided.
W.L. Lundberg; G.A. Israelson; M.D. Moeckel; S.E. Veyo; R.A. Holmes; P.R. Zafred; J.E. King; R.E. Kothmann
Process Heat Exchanger Options for the Advanced High Temperature Reactor
The work reported herein is a significant intermediate step in reaching the final goal of commercial-scale deployment and usage of molten salt as the heat transport medium for process heat applications. The primary purpose of this study is to aid in the development and selection of the required heat exchanger for power production and process heat application, which would support large-scale deployment.
Piyush Sabharwall; Eung Soo Kim; Michael McKellar; Nolan Anderson
Process Heat Exchanger Options for Fluoride Salt High Temperature Reactor
Thin Film Packaging Solutions for High Efficiency OLED Lighting Products
The objective of the 'Thin Film Packaging Solutions for High Efficiency OLED Lighting Products' project is to demonstrate thin film packaging solutions based on SiC hermetic coatings that, when applied to glass and plastic substrates, support OLED lighting devices by providing longer life with greater efficiency at lower cost than is currently available. Phase I Objective: Demonstrate thin film encapsulated working phosphorescent OLED devices on optical glass with lifetime of 1,000 hour life, CRI greater than 75, and 15 lm/W. Phase II Objective: Demonstrate thin film encapsulated working phosphorescent OLED devices on plastic or glass composite with 25 lm/W, 5,000 hours life, and CRI greater than 80. Phase III Objective: Demonstrate 2 x 2 ft{sup 2} thin film encapsulated working phosphorescent OLED with 40 lm/W, 10,000 hour life, and CRI greater than 85. This report details the efforts of Phase III (Budget Period Three), a fourteen month collaborative effort that focused on optimization of high-efficiency phosphorescent OLED devices and thin-film encapsulation of said devices. The report further details the conclusions and recommendations of the project team that have foundation in all three budget periods for the program. During the conduct of the Thin Film Packaging Solutions for High Efficiency OLED Lighting Products program, including budget period three, the project team completed and delivered the following achievements: (1) a three-year marketing effort that characterized the near-term and longer-term OLED market, identified customer and consumer lighting needs, and suggested prototype product concepts and niche OLED applications lighting that will give rise to broader market acceptance as a source for wide area illumination and energy conservation; (2) a thin film encapsulation technology with a lifetime of nearly 15,000 hours, tested by calcium coupons, while stored at 16 C and 40% relative humidity ('RH'). This encapsulation technology was characterized as having less than 10% change in transmission during the 15,000 hour test period; (3) demonstrated thin film encapsulation of a phosphorescent OLED device with 1,500 hours of lifetime at 60 C and 80% RH; (4) demonstrated that a thin film laminate encapsulation, in addition to the direct thin film deposition process, of a polymer OLED device was another feasible packaging strategy for OLED lighting. The thin film laminate strategy was developed to mitigate defects, demonstrate roll-to-roll process capability for high volume throughput (reduce costs) and to support a potential commercial pathway that is less dependent upon integrated manufacturing since the laminate could be sold as a rolled good; (5) demonstrated that low cost 'blue' glass substrates could be coated with a siloxane barrier layer for planarization and ion-protection and used in the fabrication of a polymer OLED lighting device. This study further demonstrated that the substrate cost has potential for huge cost reductions from the white borosilicate glass substrate currently used by the OLED lighting industry; (6) delivered four-square feet of white phosphorescent OLED technology, including novel high efficiency devices with 82 CRI, greater than 50 lm/W efficiency, and more than 1,000 hours lifetime in a product concept model shelf; (7) presented and or published more than twenty internal studies (for private use), three external presentations (OLED workshop-for public use), and five technology-related external presentations (industry conferences-for public use); and (8) issued five patent applications, which are in various maturity stages at time of publication. Delivery of thin film encapsulated white phosphorescent OLED lighting technology remains a challenging technical achievement, and it seems that commercial availability of thin, bright, white OLED light that meets market requirements will continue to require research and development effort. However, there will be glass encapsulated white OLED lighting products commercialized in niche markets during the 2008 calendar year. This commercializ
The first high efficiency p�-n-n + bifacial solar cells are presented. Efficiencies of 15.7 % and 13.6 % were measured under front and back air mass one illumination respectively at 28 �C. At 7 air mass one illumination and 28 �C the front efficiency increases to 16.5%. A pilot production of 200 cells was made following a fabrication process as simple as that for conventional back surface field cells. Mean efficiencies of 13.4 % and 10.7 % were obtained under front and back illumination respectively. The production yield is higher than 80%. The advantages that bifacial cells present in some applications, compared with conventional cells, have been pointed out for static [1] and quasi-static [2] concentrating systems, for luminescent concentrators [3] and also for flat panels. A transistor-like structure (n+-p-n +) has already been developed as a bifacial cell [4]. We have also suggested [5] and theoretically analysed [6] the use of a back surface field (BSF) structure (n+-p-p � or p+-n-n +) as a bifacial cell. The purpose here is to demonstrate the feasibility of high efficiency bifacial BSF solar cells. p+-n-n � bifacial cells with a 5 cm 2 area were made on float-zone silicon wafers. The resistivity of the n-type base region was 10 ~2 cm and the thickness was 260 pm. The p � and n + regions were formed by open-tube diffusions using BBr3 and POC13 sources, the resulting sheet resistance being 45- 60 ~2/[:] for the p � layer and 20- 30 ~2/[:] for the n � layer. A TiOx antireflection (AR) coating was spun onto both sides of the cell; Ti-Pd-Ag grids were sputtered and lift-off defined also on both faces. The metallization pattern was designed for the cells to operate inside static compound parabolic mirrors with a concentration factor of 5 and a non-uniform distribution of light intensity on the cell surface. The optimum grid has ten fingers per centimetre (each finger is 50- 70 pm wide) and produces a coverage factor in the illuminated area of about 5.5%.
A. Cuevas; A. Luque; J. Eguren; J. Del Alamo
High-Efficiency Nitride-Base Photonic Crystal Light Sources
The research activities performed in the framework of this project represent a major breakthrough in the demonstration of Photonic Crystals (PhC) as a competitive technology for LEDs with high light extraction efficiency. The goals of the project were to explore the viable approaches to manufacturability of PhC LEDS through proven standard industrial processes, establish the limits of light extraction by various concepts of PhC LEDs, and determine the possible advantages of PhC LEDs over current and forthcoming LED extraction concepts. We have developed three very different geometries for PhC light extraction in LEDs. In addition, we have demonstrated reliable methods for their in-depth analysis allowing the extraction of important parameters such as light extraction efficiency, modal extraction length, directionality, internal and external quantum efficiency. The information gained allows better understanding of the physical processes and the effect of the design parameters on the light directionality and extraction efficiency. As a result, we produced LEDs with controllable emission directionality and a state of the art extraction efficiency that goes up to 94%. Those devices are based on embedded air-gap PhC - a novel technology concept developed in the framework of this project. They rely on a simple and planar fabrication process that is very interesting for industrial implementation due to its robustness and scalability. In fact, besides the additional patterning and regrowth steps, the process is identical as that for standard industrially used p-side-up LEDs. The final devices exhibit the same good electrical characteristics and high process yield as a series of test standard LEDs obtained in comparable conditions. Finally, the technology of embedded air-gap patterns (PhC) has significant potential in other related fields such as: increasing the optical mode interaction with the active region in semiconductor lasers; increasing the coupling of the incident light into the active region of solar cells; increasing the efficiency of the phosphorous light conversion in white light LEDs etc. In addition to the technology of embedded PhC LEDs, we demonstrate a technique for improvement of the light extraction and emission directionality for existing flip-chip microcavity (thin) LEDs by introducing PhC grating into the top n-contact. Although, the performances of these devices in terms of increase of the extraction efficiency are not significantly superior compared to those obtained by other techniques like surface roughening, the use of PhC offers some significant advantages such as improved and controllable emission directionality and a process that is directly applicable to any material system. The PhC microcavity LEDs have also potential for industrial implementation as the fabrication process has only minor differences to that already used for flip-chip thin LEDs. Finally, we have demonstrated that achieving good electrical properties and high fabrication yield for these devices is straightforward.
James Speck; Evelyn Hu; Claude Weisbuch; Yong-Seok Choi; Kelly McGroddy; Gregor Koblmuller; Elison Matioli; Elizabeth Rangel; Fabian Rol; Dobri Simeonov
Roadmap to Improved Energy Efficiency iii 11-Sept-2009 ListA Roadmap to Improved Energy Efficiency 11-Sept-2009 Topic /A Roadmap to Improved Energy Efficiency 11-Sept-2009 Topic /
High efficiency shale oil recovery. Fifth quarterly report, January 1, 1993--March 31, 1993
The overall project objective is to demonstrate the high efficiency of the Adams Counter-Current shale oil recovery process. The efficiency will first be demonstrated on a small scale, in the current phase, after which the demonstration will be extended to the operation of a small pilot plant. Thus the immediate project objective is to obtain data on oil shale retorting operations in a small batch rotary kiln that will be representative of operations in the proposed continuous process pilot plant. Although an oil shale batch sample is sealed in the batch kiln from the start until the end of the run, the process conditions for the batch are the same as the conditions that an element of oil shale would encounter in a continuous process kiln. Similar chemical and physical conditions (heating, mixing, pyrolysis, oxidation) exist in both systems.The two most important data objectives in this phase of the project are to demonstrate (1) that the heat recovery projected for this project is reasonable and (2) that an oil shale kiln will run well and not plug up due to sticking and agglomeration. The following was completed this quarter. (1) Twelve pyrolysis runs were made on five different oil shales. All of the runs exhibited a complete absence of any plugging, tendency. Heat transfer for Green River oil shale in the rotary kiln was 84.6 Btu/hr/ft{sup 2}/{degrees}F, and this will provide for ample heat exchange in the Adams kiln. (2) One retorted residue sample was oxidized at 1000{degrees}F. Preliminary indications are that the ash of this run appears to have been completely oxidized. (3) Further minor equipment repairs and improvements were required during the course of the several runs.
High Performance Catalytic Heat Exchanger for SOFC Systems - FuelCell Energy
Catalytic Heat Catalytic Heat Exchanger for SOFC Systems-FuelCell Energy Background In a typical solid oxide fuel cell (SOFC) power generation system, hot (~900 °C) effluent gas from a catalytic combustor serves as the heat source within a high-temperature heat exchanger, preheating incoming fresh air for the SOFC's cathode. The catalytic combustor and the cathode air heat exchanger together represent the largest opportunity for cost
The Importance of Domain Size and Purity in High-Efficiency Organic...
The Importance of Domain Size and Purity in High-Efficiency Organic Solar Cells Print The efficiency of polymerorganic photovoltaic cells hinges on excitons-electronhole pairs...
Solid State Joining of High Temperature Alloy Tubes for USC and Heat-Exchanger Systems
The principal objective of this project was to develop materials enabling joining technologies for use in forward looking heat-exchanger fabrication in Brayton cycle HIPPS, IGCC, FutureGen concepts capable of operating at temperatures in excess of 1000{degree}C as well as conventional technology upgrades via Ultra Super-Critical (USC) Rankine-cycle boilers capable of operating at 760{degree}C (1400F)/38.5MPa (5500psi) steam, while still using coal as the principal fossil fuel. The underlying mission in Rankine, Brayton or Brayton-Rankine, or IGCC combined cycle heat engine is a steady quest to improving operating efficiency while mitigating global environmental concerns. There has been a progressive move to higher overall cycle efficiencies, and in the case of fossil fuels this has accelerated recently in part because of concerns about greenhouse gas emissions, notably CO{sub 2}. For a heat engine, the overall efficiency is closely related to the difference between the highest temperature in the cycle and the lowest temperature. In most cases, efficiency gains are prompted by an increase in the high temperature, and this in turn has led to increasing demands on the materials of construction used in the high temperature end of the systems. Our migration to new advanced Ni-base and Oxide Dispersion Strengthened (ODS) alloys poses significant fabrication challenges, as these materials are not readily weldable or the weld performs poorly in the high temperature creep regime. Thus the joining challenge is two-fold to a) devise appropriate joining methodologies for similar/dissimilar Ni-base and ODS alloys while b) preserving the near baseline creep performance in the welded region. Our program focus is on solid state joining of similar and dissimilar metals/alloys for heat exchanger components currently under consideration for the USC, HIPPS and IGCC power systems. The emphasis is to manipulate the joining methods and variables available to optimize joint creep performance compared to the base material creep performance. Similar and dissimilar butt joints were fabricated of MA956, IN740 alloys and using inertia welding techniques. We evaluated joining process details and heat treatments and its overall effect on creep response. Fixed and incrementally accelerated temperature creep tests were performed for similar and dissimilar joints and such incremental creep life data is compiled and reported. Long term MA956-MA556 joint tests indicate a firm 2Ksi creep stress threshold performance at 850{degree}C with a maximum exposure of over 9725 hours recorded in the current program. A Larsen Miller Parameter (LMP) of 48.50 for a 2Ksi test at 850{degree}C was further corroborated with tests at 2Ksi stress at 900{degree}C yielding a LMP=48.80. Despite this threshold the joints exhibit immense temperature sensitivity and fail promptly when test temperature raised above 900{degree}C. In comparison the performance of dissimilar joints was inferior, perhaps dictated by the creep characteristics of the mating nickel-base alloys. We describe a parametric window of joint development, and post weld heat treatment (PWHT) in dissimilar joints with solid solution (IN601, IN617) and precipitate strengthened (IN740) materials. Some concerns are evident regarding the diffusion of aluminum in dissimilar joints during high temperature recrystallization treatments. It is noted that aggressive treatments rapidly deplete the corrosion protecting aluminum reservoir in the vicinity of the joint interface. Subsequently, the impact of varying PWHT has been evaluated in the context on ensuing creep performance.
Bimal Kad
Novel Charging Station and Computational Modeling for High Thermal Conductivity Heat Pipe Thermal Ground Planes.
??Thermal ground planes (TGPs) are planar, thin (thickness of 3 mm or less) heat pipes which use two-phase heat transfer. TGPs are innovative high-performance, integrated� (more)
Ababneh, Mohammed
The Very High Temperature Reactor (VHTR) using gas-cooled reactor technology is anticipated to be the reactor type for the Next Generation Nuclear Plant (NGNP). In this reactor concept with an indirect power cycle system, a high-temperature and high integrity Intermediate Heat Exchanger (IHX) with high effectiveness is required to efficiently transfer the core thermal output to a secondary fluid for electricity generation, hydrogen production, and/or industrial process heat applications. At present, there is no proven IHX concept for VHTRs. The current Technology Readiness Level (TRL) status issued by NGNP to all components associated with the IHX for reduced nominal reactor outlet temperatures of 750�800 degrees C is 3 on a 1�10 scale, with 10 indicating omplete technological maturity. Among the various potential IHX concepts available, diffusion bonded heat exchangers (henceforth called printed circuit heat exchangers, or PCHEs) appear promising for NGNP applications. The design and fabrication of this key component of NGNP with Alloy 617, a candidate high-temperature structural material for NGNP applications, are the primary focus of this paper. In the current study, diffusion bonding of Alloy 617 has been demonstrated, although the optimum diffusion bonding process parameters to engineer a quasi interface-free joint are yet to be determined. The PCHE fabrication related processes, i.e., photochemical etching and diffusion bonding are discussed for Alloy 617 plates. In addition, the authors� experiences with these non-conventional machining and joining techniques are discussed. Two PCHEs are fabricated using Alloy 617 plates and are being experimentally investigated for their thermal-hydraulic performance in a High-Temperature Helium Facility (HTHF). The HTHF is primarily of Alloy 800H construction and is designed to facilitate experiments at temperatures and pressures up to 800 degrees C and 3 MPa, respectively. Furthermore, some preliminary microstructural and mechanical property characterization studies of representative diffusion bonded Alloy 617 specimens are presented. The characterization studies are restricted and less severe from an NGNP perspective but provide sufficient confidence to ensure safe operation of the heat exchangers in the HTHF. The test results are used to determine the design operating conditions for the PCHEs fabricated.
Sai K. Mylavarapu; Richard N. Christensen; Raymond R. Unocic; Richard E. Glosup; Mike W. Patterson
Optimal thermionic energy conversion with established electrodes for high-temperature topping and process heating
Advantages of thermionic energy conversion (TEC) have been counted and are recounted with emphasis on high-temperature service in coal-combustion products. Efficient, economical, nonpolluting utilization of coal here and now is a critically important national goal. And TEC can augment this capability not only by the often proposed topping of steam power plants but also by higher-temperature topping and process heating. For these applications, applied-research-and-technology (ART) work reveals that optimal TEC with approx. 1000-to approx. 1100 K collectors is possible using well-established tungsten electrodes. Such TEC with 1800 K emitters could approach 26.6% efficiency at 27.4 W/cm/sup 2/ with approx. 1000 K collectors and 21.7% at 22.6 W/cm/sup 2/ with approx. 1100 K collectors. These performances require 1.5- and 1.7-eV collector work functions (not the 1-eV ultimate) with nearly negligible interelectrode losses. Such collectors correspond to tungsten electrode systems in approx. 0.9-to approx. 6-torr cesium pressures with 1600-to-1900 K emitters. Because higher heat-rejection temperatures for TEC allow greater collector work functions, interelectrode-loss reduction becomes an increasingly important target for applications aimed at elevated temperatures. Studies of intragap modifications and new electrodes that will allow better electron emission and collection with lower cesium pressures are among the TEC-ART approaches to reduced interelectrode losses. These solutions will provide very effective TEC to serve directly in coal-combustion products for high-temperature topping and process heating. In turn this will help to use coal-and to use it well.
Morris, J.F.
Implications of Low Particulate Matter Emissions on System Fuel Efficiency for High Efficiency Clean Combustion
Advanced diesel combustion regimes such as High Efficiency Clean Combustion (HECC) offer the benefits of reduced engine out NOX and particulate matter (PM) emissions. Lower PM emissions during advanced combustion reduce the demand on diesel particulate filters (DPFs) and can, thereby, reduce the fuel penalty associated with DPF regeneration. In this study, a SiC DPF was loaded and regenerated on a 1.7-liter 4-cylinder diesel engine operated in conventional and advanced combustion modes at different speed and load conditions. A diesel oxidation catalyst (DOC) and a lean NOX trap (LNT) were also installed in the exhaust stream. Five steady-state speed and load conditions were weighted to estimate Federal Test Procedure (FTP) fuel efficiency. The DPF was loaded using lean-rich cycling with frequencies that resulted in similar levels of NOX emissions downstream of the LNT. The pressure drop across the DPF was measured at a standard point (1500 rpm, 5.0 bar) before and after loading, and a P rise rate was determined for comparison between conventional and advanced combustion modes. Higher PM emissions in conventional combustion resulted in a higher rate of backpressure rise across the DPF at all of the load points leading to more frequent DPF regenerations and higher fuel penalty. The fuel penalty during conventional combustion was 4.2% compared with 3.1% for a mixture of conventional and advanced modes.
Parks, II, James E [ORNL; Prikhodko, Vitaly Y [ORNL
Efficiency, Economic and Environmental Assessment of Ground Source Heat Pumps in Central Pennsylvania
The energy use of a ground-source heat pump (GSP) for heating, cooling and hot water in a Central Pennsylvania residence (namely, the author's house) is analyzed, compared to a simulation of electricity and a heating-oil furnace (with electric cooling) ...
Long titanium heat pipes for high-temperature space radiators
Titanium heat pipes are being developed to provide light weight, reliable heat rejection devices as an alternate radiator design for the Space Reactor Power System (SP-100). The radiator design includes 360 heat pipes, each of which is 5.2 m long and dissipates 3 kW of power at 775 K. The radiator heat pipes use potassium as the working fluid, have two screen arteries for fluid return, a roughened surface distributive wicking system, and a D-shaped cross-section container configuration. A prototype titanium heat pipe, 5.5-m long, has been fabricated and tested in space-simulating conditions. Results from startup and isothermal operation tests are presented. These results are also compared to theoretical performance predictions that were used to design the heat pipe initially.
Girrens, S.P.; Ernst, D.M.
Study on the Interfacial Heat Transfer Coefficient of High Pressure ...
The heat transfer behavior between an AM60B alloy casting and die during .... for Spent Nuclear Fuel and Measuring the Composition of Molten Salt by Using�...
Calibration of High Heat Flux Sensors at NIST
... sides and uniform distri- bution of flow across the tube cross section, the ... is beneficial in minimizing the stagnation point flow heat transfer effects on ...
Highly Efficient Small Form Factor LED Retrofit Lamp
This report summarizes work to develop a high efficiency LED-based MR16 lamp downlight at OSRAM SYLVANIA under US Department of Energy contract DE-EE0000611. A new multichip LED package, electronic driver, and reflector optic were developed for these lamps. At steady-state, the lamp luminous flux was 409 lumens (lm), luminous efficacy of 87 lumens per watt (LPW), CRI (Ra) of 87, and R9 of 85 at a correlated color temperature (CCT) of 3285K. The LED alone achieved 120 lumens per watt efficacy and 600 lumen flux output at 25 C. The driver had 90% electrical conversion efficiency while maintaining excellent power quality with power factor >0.90 at a power of only 5 watts. Compared to similar existing MR16 lamps using LED sources, these lamps had much higher efficacy and color quality. The objective of this work was to demonstrate a LED-based MR16 retrofit lamp for replacement of 35W halogen MR16 lamps having (1) luminous flux of 500 lumens, (2) luminous efficacy of 100 lumens per watt, (3) beam angle less than 40{sup o} and center beam candlepower of at least 1000 candelas, and (4) excellent color quality.
Steven Allen; Fred Palmer; Ming Li
Processes for producing low cost, high efficiency silicon solar cells
Processes which utilize rapid thermal processing (RTP) are provided for inexpensively producing high efficiency silicon solar cells. The RTP processes preserve minority carrier bulk lifetime .tau. and permit selective adjustment of the depth of the diffused regions, including emitter and back surface field (bsf), within the silicon substrate. In a first RTP process, an RTP step is utilized to simultaneously diffuse phosphorus and aluminum into the front and back surfaces, respectively, of a silicon substrate. Moreover, an in situ controlled cooling procedure preserves the carrier bulk lifetime .tau. and permits selective adjustment of the depth of the diffused regions. In a second RTP process, both simultaneous diffusion of the phosphorus and aluminum as well as annealing of the front and back contacts are accomplished during the RTP step. In a third RTP process, the RTP step accomplishes simultaneous diffusion of the phosphorus and aluminum, annealing of the contacts, and annealing of a double-layer antireflection/passivation coating SiN/SiO.sub.x. In a fourth RTP process, the process of applying front and back contacts is broken up into two separate respective steps, which enhances the efficiency of the cells, at a slight time expense. In a fifth RTP process, a second RTP step is utilized to fire and adhere the screen printed or evaporated contacts to the structure.
Rohatgi, Ajeet (Marietta, GA); Doshi, Parag (Altanta, GA); Tate, John Keith (Lawrenceville, GA); Mejia, Jose (Atlanta, GA); Chen, Zhizhang (Duluth, GA)
Processes which utilize rapid thermal processing (RTP) are provided for inexpensively producing high efficiency silicon solar cells. The RTP processes preserve minority carrier bulk lifetime {tau} and permit selective adjustment of the depth of the diffused regions, including emitter and back surface field (bsf), within the silicon substrate. In a first RTP process, an RTP step is utilized to simultaneously diffuse phosphorus and aluminum into the front and back surfaces, respectively, of a silicon substrate. Moreover, an in situ controlled cooling procedure preserves the carrier bulk lifetime {tau} and permits selective adjustment of the depth of the diffused regions. In a second RTP process, both simultaneous diffusion of the phosphorus and aluminum as well as annealing of the front and back contacts are accomplished during the RTP step. In a third RTP process, the RTP step accomplishes simultaneous diffusion of the phosphorus and aluminum, annealing of the contacts, and annealing of a double-layer antireflection/passivation coating SiN/SiO{sub x}. In a fourth RTP process, the process of applying front and back contacts is broken up into two separate respective steps, which enhances the efficiency of the cells, at a slight time expense. In a fifth RTP process, a second RTP step is utilized to fire and adhere the screen printed or evaporated contacts to the structure. 28 figs.
Rohatgi, A.; Doshi, P.; Tate, J.K.; Mejia, J.; Chen, Z.
Processes which utilize rapid thermal processing (RTP) are provided for inexpensively producing high efficiency silicon solar cells. The RTP processes preserve minority carrier bulk lifetime .tau. and permit selective adjustment of the depth of the diffused regions, including emitter and back surface field (bsf), within the silicon substrate. Silicon solar cell efficiencies of 16.9% have been achieved. In a first RTP process, an RTP step is utilized to simultaneously diffuse phosphorus and aluminum into the front and back surfaces, respectively, of a silicon substrate. Moreover, an in situ controlled cooling procedure preserves the carrier bulk lifetime .tau. and permits selective adjustment of the depth of the diffused regions. In a second RTP process, both simultaneous diffusion of the phosphorus and aluminum as well as annealing of the front and back contacts are accomplished during the RTP step. In a third RTP process, the RTP step accomplishes simultaneous diffusion of the phosphorus and aluminum, annealing of the contacts, and annealing of a double-layer antireflection/passivation coating SiN/SiO.sub.x.
Rohatgi, Ajeet (Marietta, GA); Chen, Zhizhang (Duluth, GA); Doshi, Parag (Atlanta, GA)
High Efficiency Driving Electronics for General Illumination LED Luminaires
New generation of standalone LED driver platforms developed, which are more efficient These LED Drivers are more efficient (?90%), smaller in size ( 0.15 in3/watt), lower in cost ( 12 cents/watt in high volumes in millions of units). And these products are very reliable having an operating life of over 50,000 hours. This technology will enable growth of LED light sources in the use. This will also help in energy saving and reducing total life cycle cost of LED units. Two topologies selected for next generation of LED drivers: 1) Value engineered single stage Flyback topology. This is suitable for low powered LED drivers up to 50W power. 2) Two stage boost power factor correction (PFC) plus LLC half bridge platform for higher powers. This topology is suitable for 40W to 300W LED drivers. Three new product platforms were developed to cover a wide range of LED drivers: 1) 120V 40W LED driver, 2) Intellivolt 75W LED driver, & 3) Intellivolt 150W LED driver. These are standalone LED drivers for rugged outdoor lighting applications. Based on these platforms number of products are developed and successfully introduced in the market place meeting key performance, size and cost goals.
Upadhyay, Anand
City of High Point Electric - Commercial Energy Efficiency Grant...
Technologies Lighting, Chillers, Furnaces, Boilers, Heat pumps, Central Air conditioners, Energy Mgmt. SystemsBuilding Controls, CaulkingWeather-stripping, DuctAir sealing,...
Controlled Photolytic Release of Biocides for High Efficiency ...
Abstract Scope, Airborne microorganisms�bacteria, viruses, and fungi�that enter heating, ventilation and air conditioning (HVAC) systems, and deposit on�...
Performance correlations for high temperature potassium heat pipes
Potassium heat pipes designed for operation at a nominal temperature of 775K have been developed for use in a heat pipe cooled reactor design. The heat pipes operate in a gravity assist mode with a maximum required power throughput of approximately 16 kW per heat pipe. Based on a series of sub-scale experiments with 2.12 and 3.2 cm diameter heat pipes the prototypic heat pipe diameter was set at 5.7 cm with a simple knurled wall wick used in the interests of mechanical simplicity. The performance levels required for this design had been demonstrated in prior work with gutter assisted wicks and emphasis in the present work was on the attainment of similar performance with a simplified wick structure. The wick structure used in the experiment consisted of a pattern of knurled grooves in the internal wall of the heat pipe. The knurl depth required for the planned heat pipe performance was determined by scaling of wick characteristic data from the sub-scale tests. These tests indicated that the maximum performance limits of the test heat pipes did not follow normal entrainment limit predictions for textured wall gravity assist heat pipes. Test data was therefore scaled to the prototype design based on the assumption that the performance was controlled by an entrainment parameter based on the liquid flow depth in the groove structure. This correlation provided a reasonable fit to the sub-scale test data and was used in scale up of the design from the 8.0 cm/sup 2/ cross section of the largest sub-scale heat pipe to the 25.5 cm/sup 2/ cross section prototype. Correlation of the model predictions with test data from the prototype is discussed.
Merrigan, M.A.; Keddy, E.S.; Sena, J.T.
Improved efficiency and precise temperature control of low-frequency induction-heating pure iron vapor source on ECR ion source
Multiply charged ions to be used prospectively are produced from solid pure material in an electron cyclotron resonance ion source (ECRIS). Recently a pure iron source is also required for the production of caged iron ions in the fullerene in order to control cells in vivo in bio-nano science and technology. We adopt directly heating iron rod by induction heating (IH) because it has non-contact with insulated materials which are impurity gas sources. We choose molybdenum wire for the IH coils because it doesn't need water cooling. To improve power efficiency and temperature control, we propose to the new circuit without previously using the serial and parallel dummy coils (SPD) for matching and safety. We made the circuit consisted of inductively coupled coils which are thin-flat and helix shape, and which insulates the IH power source from the evaporator. This coupling coils circuit, i.e. insulated induction heating coil transformer (IHCT), can be move mechanically. The secondary current can be adjusted precisely and continuously. Heating efficiency by using the IHCT is much higher than those of previous experiments by using the SPD, because leakage flux is decreased and matching is improved simultaneously. We are able to adjust the temperature in heating the vapor source around melting point. And then the vapor pressure can be controlled precisely by using the IHCT. We can control {+-}10K around 1500 Degree-Sign C by this method, and also recognize to controlling iron vapor flux experimentally in the extreme low pressures. Now we come into next stage of developing induction heating vapor source for materials with furthermore high temperature melting points above 2000K with the IHCT, and then apply it in our ECRIS.
Kato, Y.; Takenaka, T.; Yano, K.; Kiriyama, R.; Kurisu, Y.; Nozaki, D.; Muramatsu, M.; Kitagawa, A.; Uchida, T.; Yoshida, Y.; Sato, F.; Iida, T. [Osaka Univ., 2-1 Yamadaoka, Suita, Osaka, 565-0871 (Japan); National Institute of Radiological Science (NIRS), 4-9-1 Anagawa, Inage, Chiba, 263-8555 (Japan); Bio-Nano Electronics Research Centre, Toyo Univ., 2100 Kuzirai, Kawagoe, Saitama, 350-8585 (Japan); Osaka Univ., 2-1 Yamadaoka, Suita, Osaka, 565-0871 (Japan)
Demonstration of a Highly Efficient Solid Oxide Fuel Cell Power System Using Adiabatic Steam Reforming and Anode Gas Recirculation
Solid oxide fuel cells (SOFC) are currently being developed for a wide variety of applications because of their high efficiency at multiple power levels. Applications for SOFCs encompass a large range of power levels including 1-2 kW residential combined heat and power applications, 100-250 kW sized systems for distributed generation and grid extension, and MW-scale power plants utilizing coal. This paper reports on the development of a highly efficient, small-scale SOFC power system operating on methane. The system uses adiabatic steam reforming of methane and anode gas recirculation to achieve high net electrical efficiency. The anode exit gas is recirculated and all of the heat and water required for the endothermic reforming reaction are provided by the anode gas emerging from the SOFC stack. Although the single-pass fuel utilization is only about 55%, because of the anode gas recirculation the overall fuel utilization is up to 93%. The demonstrated system achieved gross power output of 1650 to 2150 watts with a maximum net LHV efficiency of 56.7% at 1720 watts. Overall system efficiency could be further improved to over 60% with use of properly sized blowers.
Powell, Michael R.; Meinhardt, Kerry D.; Sprenkle, Vincent L.; Chick, Lawrence A.; Mcvay, Gary L.
Method and Apparatus for High-Efficiency Direct Contact Condensation
clean energy. But continuing to produce geothermal power efficiently and economically requires innovative adjustments to the technology used to ...
High Efficiency Generation of Hydrogen Fuels using Nuclear Power Annual Report August, 2000 - July 2001
OAK B188 High Efficiency Generation of Hydrogen Fuels using Nuclear Power Annual Report August 2000 - July 2001. Currently no large scale, cost-effective, environmentally attractive hydrogen production process is available for commercialization nor has such a process been identified. Hydrogen is a promising energy carrier, which potentially could replace the fossil fuels used in the transportation sector of our economy. Carbon dioxide emissions from fossil fuel combustion are thought to be responsible for global warming. The purpose of this work is to determine the potential for efficient, cost-effective, large-scale production of hydrogen utilizing high temperature heat from an advanced nuclear power station. The benefits of this work will include the generation of a low-polluting transportable energy feedstock in an efficient method that has little or no implication for greenhouse gas emissions from a primary energy source whose availability and sources are domestically controlled. This will help to ensure energy for a future transportation/energy infrastructure that is not influenced/controlled by foreign governments. This report describes work accomplished during the second year (Phase 2) of a three year project whose objective is to ''define an economically feasible concept for production of hydrogen, by nuclear means, using an advanced high temperature nuclear reactor as the energy source.'' The emphasis of the first year (Phase 1) was to evaluate thermochemical processes which offer the potential for efficient, cost-effective, large-scale production of hydrogen from water, in which the primary energy input is high temperature heat from an advanced nuclear reactor and to select one (or, at most, three) for further detailed consideration. Phase 1 met its goals and did select one process, the sulfur-iodine process, for investigation in Phases 2 and 3. The combined goals of Phases 2 and 3 were to select the advanced nuclear reactor best suited to driving the selected thermochemical process and to define the selected reactor and process to the point that capital costs, operating costs and the resultant cost of hydrogen can be estimated. During original contract negotiation, it was necessary to reduce work scope to meet funding limits. As a result, the reactor interface and process will not be iterated to the point that only hydrogen is produced. Rather, hydrogen and electricity will be co-generated and the hydrogen cost will be stated as a function of the electricity sales price.
Brown, L.C.
High efficiency shale oil recovery. Fourth quarterly report, October 1, 1992--December 31, 1992
High-efficiency photovoltaics based on semiconductor nanostructures
The objective of this project was to exploit a variety of semiconductor nanostructures, specifically semiconductor quantum wells, quantum dots, and nanowires, to achieve high power conversion efficiency in photovoltaic devices. In a thin-film device geometry, the objectives were to design, fabricate, and characterize quantum-well and quantum-dot solar cells in which scattering from metallic and/or dielectric nanostructures was employed to direct incident photons into lateral, optically confined paths within a thin (~1-3um or less) device structure. Fundamental issues concerning nonequilibrium carrier escape from quantum-confined structures, removal of thin-film devices from an epitaxial growth substrate, and coherent light trapping in thin-film photovoltaic devices were investigated. In a nanowire device geometry, the initial objectives were to engineer vertical nanowire arrays to optimize optical confinement within the nanowires, and to extend this approach to core-shell heterostructures to achieve broadspectrum absorption while maintaining high opencircuit voltages. Subsequent work extended this approach to include fabrication of nanowire photovoltaic structures on low-cost substrates.
Yu, Paul K.L. [University of California, San Diego; Yu, Edward T. [University of Texas at Austin; Wang, Deli [University of California, San Diego
Boost Process Heating Efficiency, Software Tools for Industry, Industrial Technologies Program (ITP) (Fact Sheet)
This fact sheet describes how the Industrial Technologies Program Process Heating Assessment and Survey Tool (PHAST) can help industrial plants indentify opportunities to save energy.
Continuous flow microwave heating : evaluation of system efficiency and enzyme inactivation kinetics.
??A continuous flow microwave heating system was set up by using one domestic microwave oven (1000W nominal output at 2450MHz). Water was run through the� (more)
Lin, Man Guang, 1966-
Highly ordered Zn-doped mesoporous silica: An efficient catalyst for transesterification reaction
Designing highly ordered material with nanoscale periodicity is of great significance in the field of solid state chemistry. Herein, we report the synthesis of highly ordered 2D-hexagonal mesoporous zinc-doped silica using a mixture of anionic and cationic surfactants under hydrothermal conditions. Powder XRD, N{sub 2} sorption, TEM analysis revealed highly ordered 2D-hexagonal arrangements of the pores with very good surface area (762 m{sup 2} g{sup -1}) in this Zn-rich mesoporous material. Chemical analysis shows very high loading of zinc (ca. 12.0 wt%) in the material together with retention of hexagonal pore structure. Interestingly, high temperature calcination resulted into zinc silicate phase, unlike any ZnO phase, which otherwise is expected under heat treatments. High surface area together with Zn loading in this mesoporous material has been found useful for the catalytic activity of the materials in the acid-catalyzed transesterification reactions of various esters under mild liquid phase conditions. - Graphical abstract: Zn-rich 2D-hexagonal mesoporous materials are synthesized hydrothermally, which show very good catalytic activity in the transesterification reaction under mild liquid phase reaction conditions. Highlights: > Zn-rich 2D-hexagonal mesoporous silica. > High surface area material. > Efficient catalyst in liquid phase transesterification reaction. > Biodiesel production.
Pal, Nabanita; Paul, Manidipa [Department of Materials Science, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032 (India); Bhaumik, Asim, E-mail: firstname.lastname@example.com [Department of Materials Science, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032 (India)
Cost-efficient monitoring of water quality in district heating systems This article examines the monitoring strategy for water quality in a large Danish district
Cost-efficient monitoring of water quality in district heating systems This article examines the monitoring strategy for water quality in a large Danish district heating system and makes a proposal for a technical and economic improvement. Monitoring of water quality in district heating systems is necessary
High-Efficiency Thermal Energy High-Efficiency Thermal Energy Storage System for CSP to someone by E-mail Share SunShot Initiative: High-Efficiency Thermal Energy Storage System for CSP on Facebook Tweet about SunShot Initiative: High-Efficiency Thermal Energy Storage System for CSP on Twitter Bookmark SunShot Initiative: High-Efficiency Thermal Energy Storage System for CSP on Google Bookmark SunShot Initiative: High-Efficiency Thermal Energy Storage System for CSP on Delicious Rank SunShot Initiative: High-Efficiency Thermal Energy Storage System for CSP on Digg Find More places to share SunShot Initiative: High-Efficiency Thermal Energy Storage System for CSP on AddThis.com... Concentrating Solar Power Systems Components Competitive Awards CSP Research & Development Thermal Storage CSP Recovery Act
Keystone HELP- EnergyWorks Efficiency Loan Program
The Keystone HELP Program is designed to help homeowners improve energy efficiency with special financing for high-efficiency heating, air conditioning, insulation, windows, doors, and �whole house...
Keystone HELP - EnergyWorks Efficiency Loan Program (Pennsylvania...
12122012 References DSIRE1 Summary The Keystone HELP Program is designed to help homeowners improve energy efficiency with special financing for high-efficiency heating, air...
Heat transfer and pressure drop data for high heat flux densities to water at high subcritical pressures
Local surface ooeffioients of heat t-ansfer, overall pressure drop data and mean friction factor are presented for heat flamms up to 3.52106 BtuAr ft2 for water flowing in a nickel tabe isder the following conditions: mass ...
Rohsenow, Warren M.
High-Efficiency Nitride-Based Solid-State Lighting
In this final technical progress report we summarize research accomplished during Department of Energy contract DE-FC26-01NT41203, entitled ''High-Efficiency Nitride-Based Solid-State Lighting''. Two teams, from the University of California at Santa Barbara (Principle Investigator: Dr. Shuji Nakamura) and the Lighting Research Center at Rensselaer Polytechnic Institute (led by Dr. N. Narendran), pursued the goals of this contract from thin film growth, characterization, and packaging/luminaire design standpoints. The UCSB team initially pursued the development of blue gallium nitride (GaN)-based vertical-cavity surface-emitting lasers, as well as ultraviolet GaN-based light emitting diodes (LEDs). In Year 2, the emphasis shifted to resonant-cavity light emitting diodes, also known as micro-cavity LEDs when extremely thin device cavities are fabricated. These devices have very directional emission and higher light extraction efficiency than conventional LEDs. Via the optimization of thin-film growth and refinement of device processing, we decreased the total cavity thickness to less than 1 {micro}m, such that micro-cavity effects were clearly observed and a light extraction efficiency of over 10% was reached. We also began the development of photonic crystals for increased light extraction, in particular for so-called ''guided modes'' which would otherwise propagate laterally in the device and be re-absorbed. Finally, we pursued the growth of smooth, high-quality nonpolar a-plane and m-plane GaN films, as well as blue light emitting diodes on these novel films. Initial nonpolar LEDs showed the expected behavior of negligible peak wavelength shift with increasing drive current. M-plane LEDs in particular show promise, as unpackaged devices had unsaturated optical output power of {approx} 3 mW at 200 mA drive current. The LRC's tasks were aimed at developing the subcomponents necessary for packaging UCSB's light emitting diodes, and packaging them to produce a white light fixture. During the third and final year of the project, the LRC team investigated alternate packaging methods for the white LED device to achieve at least 25 percent more luminous efficacy than traditional white LEDs; conducted optical ray-tracing analyses and human factors studies to determine the best form factor for the white light source under development, in terms of high luminous efficacy and greater acceptance by subjects; and developed a new die encapsulant using silicone-epoxy resins that showed less yellowing and slower degradation. At the conclusion of this project, the LRC demonstrated a new packaging method, called scattered photon extraction (SPE), that produced an average luminous flux and corresponding average efficacy of 90.7 lm and 36.3 lm/W, respectively, compared with 56.5 lm and 22.6 lm/W for a similar commercial white LED package. At low currents, the SPE package emitted white light with an efficacy of over 80 lm/W and had chromaticity values very close to the blackbody locus. The SPE package showed an overall improvement of 61% for this particular comparison, exceeding the LRC's third-year goal of 25% improvement.
Paul T. Fini; Shuji Nakamura
Development of manufacturing capability for high-concentration, high-efficiency silicon solar cells
This report presents a summary of the major results from a program to develop a manufacturable, high-efficiency silicon concentrator solar cell and a cost-effective manufacturing facility. The program was jointly funded by the Electric Power Research Institute, Sandia National Laboratories through the Concentrator Initiative, and SunPower Corporation. The key achievements of the program include the demonstration of 26%-efficient silicon concentrator solar cells with design-point (20 W/cm{sup 2}) efficiencies over 25%. High-performance front-surface passivations; that were developed to achieve this result were verified to be absolutely stable against degradation by 475 days of field exposure at twice the design concentration. SunPower demonstrated pilot production of more than 1500 of these cells. This cell technology was also applied to pilot production to supply 7000 17.7-cm{sup 2} one-sun cells (3500 yielded wafers) that demonstrated exceptional quality control. The average efficiency of 21.3% for these cells approaches the peak efficiency ever demonstrated for a single small laboratory cell within 2% (absolute). Extensive cost models were developed through this program and calibrated by the pilot-production project. The production levels achieved indicate that SunPower could produce 7-10 MW of concentrator cells per year in the current facility based upon the cell performance demonstrated during the program.
Sinton, R.A.; Verlinden, P.J.; Crane, R.A.; Swanson, R.N. [SunPower Corp., Sunnyvale, CA (United States)
High Operating Temperature Heat Transfer Fluids for Solar Thermal...
Heat Transfer Fluids for Solar Thermal Power Generation UCLA, UCB, Yale Award Number: DE-EE0005941 | January 9, 2013 | Sungtaek Ju 1.1 Thermochemistry modeling Identified promising...
Failure Analysis of the Heat Exchanger Tubes Exposed to High ...
The bundle of the heat exchanger was removed from service after 8 years for metallurgical investigation. The tube side contains boiler feed water at 622oF and �...
Low Temperature Combustion Demonstrator for High Efficiency Clean Combustion
The project which extended from November 2005 to May of 2010 demonstrated the application of Low Temperature Combustion (LTC) with engine out NOx levels of 0.2 g/bhp-hr throughout the program target load of 12.6bar BMEP. The project showed that the range of loads could be extended to 16.5bar BMEP, therefore matching the reference lug line of the base 2007 MY Navistar 6.4L V8 engine. Results showed that the application of LTC provided a dramatic improvement over engine out emissions when compared to the base engine. Furthermore LTC improved thermal efficiency by over 5% from the base production engine when using the steady state 13 mode composite test as a benchmark. The key enablers included improvements in the air, fuel injection, and cooling systems made in Phases I and II. The outcome was the product of a careful integration of each component under an intelligent control system. The engine hardware provided the conditions to support LTC and the controller provided the necessary robustness for a stable combustion. Phase III provided a detailed account on the injection strategy used to meet the high load requirements. During this phase, the control strategy was implemented in a production automotive grade ECU to perform cycle-by-cycle combustion feedback on each of the engine cylinders. The control interacted on a cycle base with the injection system and with the Turbo-EGR systems according to their respective time constants. The result was a unique system that could, first, help optimize the combustion system and maintain high efficiency, and secondly, extend the steady state results to the transient mode of operation. The engine was upgraded in Phase IV with a Variable Valve Actuation system and a hybrid EGR loop. The impact of the more versatile EGR loop did not provide significant advantages, however the application of VVA proved to be an enabler to further extend the operation of LTC and gain considerable benefits in fuel economy and soot reduction. Finally, the transient demonstration was performed in Phase IV. The project demonstrated the achievement of meeting US10 emissions without NOx aftertreatment. The successful execution of the project has served to highlight the effectiveness of closely matched combustion predictive tools to engine testing. It has further served to highlight the importance of key technologies and future areas of research and development. In this regard, recommendations are made towards further improvements in the areas of engine hardware, fuel injection systems, controls and fuels.
Ojeda, William de
Project: Novel Working Fluids for High-Efficiency HVAC&R ...
... of the best replacements for high-GWP hydrofluorocarbon (HFC) refrigerants; and to demonstrate improved energy efficiency of chillers through ...
Highly efficient blue organic light emitting devices with indium-free transparent anode on flexible substrates
Indium-free transparent conducting oxides may provide a lower cost solution for the transparent anode in flexible displays and energy efficient solid state lighting. We report herein a near room temperature sputtering process for generating an indium-free transparent conductive oxide (TCO) coating on a flexible substrate. Specifically, we deposited gallium-doped zinc oxide (GZO) uniformly over a 12� diameter area at room temperature on polyethylene terephthalate (PET). During deposition, the system heats to about 60oC due to the energetic sputtering conditions, without any noticeable damage to the PET substrate. The GZO films exhibit excellent physical, optical and electrical properties: roughness ~7 nm, transmittance >85% and resistivity ~ 10-3 ohm� cm. Phosphorescent blue organic light-emitting devices (OLEDs) were fabricated on these substrates with comparable performance (16% external quantum efficiency and 33 lm/W power efficiency at 1mA/cm2) to that of devices fabricated on GZO (or ITO) deposited on glass substrates, suggesting flexible GZO/PET substrates may be used instead of high-cost and rigid ITO and glass for flexible displays and solid state lighting.
Wang, Liang; Swensen, James S.; Polikarpov, Evgueni; Matson, Dean W.; Bonham, Charles C.; Bennett, Wendy D.; Gaspar, Daniel J.; Padmaperuma, Asanga B.
Demonstration of High Efficiency Elastocaloric Cooling with Large Delta- T Using NiTi Wires
Vapor compression (VC) is by far the most dominant technology for meeting all cooling and refrigeration needs around the world. It is a mature technology with the efficiency of modern compressors approaching the theoretical limit, but its envi-ronmental footprint remains a global problem. VC refrigerants such as hydrochlo-roflurocarbons (HCFCs) and hydrofluorocarbons (HFCs) are a significant source of green house gas (GHG) emissions, and their global warming potential (GWP) is as high as 1000 times that of CO2. It is expected that building space cooling and re-frigeration alone will amount to {approx} 5% of primary energy consumption and {approx}5% of all CO2 emission in U.S. in 2030 . As such, there is an urgent need to develop an al-ternative high-efficiency cooling technology that is affordable and environmentally friendly. Among the proposed candidates, magnetocaloric cooling (MC) is currently received a lot of attention because of its high efficiency. However, MC is inherently expensive because of the requirement of large magnetic field and rare earth materi-als. Here, we demonstrate an entirely new type of solid-state cooling mechanism based on the latent heat of reversible martensitic transformation. We call it elasto-caloric cooling (EC) after the superelastic transformation of austenite it utilizes. The solid-state refrigerant of EC is cost-effective, and it completely eliminates the use of any refrigerants including HCFCs/HFCs. We show that the COP (coefficient of per-formance) of a jugular EC with optimized materials can be as high as > 10 with measured {Delta}T of 17 C.
Cui, Jun; Wu, Yiming; Muehlbauer, Jan; Hwang, Yunho; Radermacher, Reinhard; Fackler, Sean; Wuttig, Manfred; Takeuchi, Ichiro
Refrigerant Cooled using local water cooled refrigerant pumps SGI Altix 4700 Rear Door Heat Exchanger using central chilled water Site 2A SGI Altix Ice 8200 Air cooled Cray XT5...
Design of Bulk Nanocomposites as High Efficiency Thermoelectric...
structure as the host material breaks thermoelectric efficiency records by blocking thermal, but not electrical, conductivity. Significance and Impact A new strategy to design...
tools to evaluate cost and energy implications of efficiencytools to evaluate cost and energy implications of efficiencyand low first cost, not energy efficiency. Utilization of �
Rational Device Design for Highly Efficient Organic Photovoltaic Solar Cells.
??Abundant, scalable, environmentally-friendly organic photovoltaic (OPV) technology is increasingly promising in recent years. The power conversion efficiency (PCE) of OPVs has been raised to around� (more)
Yang, Bin
for efficient and meaningful sub-metering. � Develop&architecture to facilitate sub-metering � Include sub-metersintermingled, making sub-metering expensive and complicated.
High Efficiency Multiple-Junction Solar Cells - Energy ...
Technology Marketing Summary Single junction solar cells have limited efficiency and fail to extract maximum energy from photons outside of a specific ...
Available Technologies: Highly Efficient Multigap Solar Cell Materials
Scientists at Berkeley Lab have invented multiband gap semiconducting materials for developing solar cells that could achieve power conversion efficiencies of 50 ...
Southwest Gas Corporation - Commercial High-Efficiency Equipment...
who purchase energy efficient natural gas equipment. Eligible equipment includes natural gas storage and tankless water heaters, boiler equipment, griddles, fryers, conveyor ovens,...
Sandia National Laboratories High Efficiency Multiple-Junction ...
Sandia National Laboratories TECHNOLOGY SUMMARY Single junction solar cells have limited efficiency and fail to extract maximum energy from photons outside of a specific
Northwest Energy Efficient Manufactured Housing Program: High Performance Manufactured Home Prototyping and Construction Development
The Building America Partnership for Improved Residential Construction, the Bonneville Power Administration (BPA), and Northwest Energy Works (NEW), the current Northwest Energy Efficient Manufactured Housing Program (NEEM) administrator, have been collaborating to conduct research on new specifications that would improve on the energy requirements of a NEEM home. In its role as administrator, NEW administers the technical specs, performs research and engineering analysis, implements ongoing construction quality management procedures, and maintains a central database with home tracking. This project prototyped and assessed the performances of cost-effective high performance building assemblies and mechanical systems that are not commonly deployed in the manufacturing setting. The package of measures is able to reduce energy used for space conditioning, water heating and lighting by 50 percent over typical manufactured homes produced in the northwest.
Hewes, T.; Peeks, B.
In this second annual report we summarize the progress in the second-year period of Department of Energy contract DE-FC26-01NT41203, entitled ''High- Efficiency Nitride-Based Solid-State Lighting''. The two teams, from the University of California at Santa Barbara (Principle Investigator: Dr. Shuji Nakamura) and Rensselaer Polytechnic Institute (led by Dr. N. Narendran), are pursuing the goals of this contract from thin film growth, characterization, and packaging standpoints. The UCSB team has recently made significant progress in the development of light-emitting diodes (LEDs) with AlGaN active regions emitting in the ultraviolet (UV), resonant-cavity LEDs (RCLEDs), as well as lateral epitaxial overgrowth (LEO) techniques to obtain large-area non-polar GaN films with low average dislocation density. The Rensselaer team has benchmarked the performance of commercially available LED systems and has also conducted efforts to develop an optimized RCLED packaging scheme, including development of advanced epoxy encapsulant chemistries.
Heat transfer mechanism with thin filaments including ceramic high temperature heat exchanger
A radiative heat transfer mechanism in a furnace having burners through which pulverized coal and air are burned producing combustion gases and contaminants. A plurality of elongated conduits are positioned inside the furnace proximate to the burners generally parallel to the flow of combustion gases in the furnace. A plurality of thin filaments are inside each of the elongated hollow conduits, the filaments having diameters in the range of from about 1 micrometer to about 1,000 micrometers and having an infrared radiation cross-section sufficient to cause the filaments to heat upon exposure to infrared radiation. Blower mechanism is associated with the elongated conduits for limiting the amount of soot and ash which deposit on the conduits to preserve the radiative and convective transfer of heat energy from the combustion gases to the conduits.
Im, Kwan H. (Naperville, IL); Ahluwalia, Rajesh K. (Burr Ridge, IL)
A radiative heat transfer mechanism in a furnace is described having burners through which pulverized coal and air are burned producing combustion gases and contaminants. A plurality of elongated conduits are positioned inside the furnace proximate to the burners generally parallel to the flow of combustion gases in the furnace. A plurality of thin filaments are inside each of the elongated hollow conduits, the filaments having diameters in the range of from about 1 micrometer to about 1,000 micrometers and having an infrared radiation cross-section sufficient to cause the filaments to heat upon exposure to infrared radiation. Blower mechanism is associated with the elongated conduits for limiting the amount of soot and ash which deposit on the conduits to preserve the radiative and convective transfer of heat energy from the combustion gases to the conduits. 7 figs.
Im, K.H.; Ahluwalia, R.K.
Novel Morphology of Highly Efficient Two-phase Ferrite Cores for ...
This discovery may very well usher in a new chapter in high efficiency power cores for high frequency inductors, transformers, power supplies, converters, and
Device and method for electron beam heating of a high density plasma
A device and method for relativistic electron beam heating of a high density plasma in a small localized region. A relativistic electron beam generator produces a high voltage electron beam which propagates along a vacuum drift tube and is modulated to initiate electron bunching within the beam. The beam is then directed through a low density gas chamber which provides isolation between the vacuum modulator and the relativistic electron beam target. The relativistic beam is then applied to a high density target plasma which typically comprises DT, DD, hydrogen boron or similar thermonuclear gas at a density of 10.sup.17 to 10.sup.20 electrons per cubic centimeter. The target plasma is ionized prior to application of the electron beam by means of a laser or other preionization source. Utilizing a relativistic electron beam with an individual particle energy exceeding 3 MeV, classical scattering by relativistic electrons passing through isolation foils is negligible. As a result, relativistic streaming instabilities are initiated within the high density target plasma causing the relativistic electron beam to efficiently deposit its energy into a small localized region within the high density plasma target.
Thode, Lester E. (Los Alamos, NM)
Absorption heat pump system
An improvement in an absorption heat pump cycle is obtained by adding adiabatic absorption and desorption steps to the absorber and desorber of the system. The adiabatic processes make it possible to obtain the highest temperature in the absorber before any heat is removed from it and the lowest temperature in the desorber before heat is added to it, allowing for efficient utilization of the thermodynamic availability of the heat supply stream. The improved system can operate with a larger difference between high and low working fluid concentrations, less circulation losses, and more efficient heat exchange than a conventional system.
Grossman, Gershon (Oak Ridge, TN); Perez-Blanco, Horacio (Knoxville, TN)
Study of high energy ion loss during hydrogen minority heating in TFTR
High energy ion loss during hydrogen minority ICRF heating is measured and compared with the loss of the D-D fusion products. During H minority heating a relatively large loss of high energy ions is observed at 45{degrees} below the outer midplane, with or without simultaneous NBI heating. This increase is most likely due to a loss of the minority tail protons, a possible model for this process is described.
Park, J.; Zweben, S.J.
Numerical study of high heat ux pool boiling heat transfer Ying He a,*, Masahiro Shoji b
in saturated pool boiling. In this model the analysis of heat conduction within the heater is added on the heater surface itself [10]. Bhat et al. [11] put forward a theoretical model of macrolayer formation to their model and ob- tained the simulated boiling curve of water. In addition, they compared Haramura and Katto
Maruyama, Shigeo
Relative Efficiencies of Turbulent Transfer of Heat, Mass, and Momentum over a Patchy Urban Surface
This study uses observational data from a suburban site in Vancouver, British Columbia, Canada, to investigate the relative facility with which heat, water vapor, and momentum are transported by turbulence in the unstable surface layer. The ...
M. Roth; T. R. Oke
Handbook of radiative heat transfer in high-temperature gases
This work offers both an original method for calculating optical properties of low-temperature plasma at elevated densities ... and an effective new means for calculating radiative heat transfer in hot gases and plasma with arbitrary temperature and pressure distributions. These methods allow for automatic accounting of all details of the plasma spectrum, including the line structure. This volume contains radiant transfer in problems of heat transfer; integration over frequency; methods of partial characteristics; method of effective populations; calculation of partial characteristics; appendix: tabular data.
Soloukhin, R.I.; Golovnev, I.F.; Zamurayev, V.P.; Katsnelson, S.S.; Kovalskaya, G.A.; Sevastyanenko, V.G.; Soloukhin, R.I.
Use of the Dryer Off-gas Latent Heat for Improved Energy Efficiency ...
... resulting in further reduction in energy consumption by additional 20-30 %. Energy efficiency and technology of this new innovation is discussed in the paper
comparison of VAV and VRF air conditioning systems in anThe variable refrigerant flow (VRF) and ground source heatthe energy efficiency of VRF systems compared with GSHP
Device for plasma confinement and heating by high currents and nonclassical plasma transport properties
A toroidal plasma containment device having means for inducing high total plasma currents and current densities and at the same time emhanced plasma heating, strong magnetic confinement, high energy density containment, magnetic modulation, microwaveinduced heating, and diagnostic accessibility is described. (Official Gazette)
Coppi, B.; Montgomery, D.B.
Alternatives Generation and Analysis for Heat Removal from High Level Waste Tanks
This document addresses the preferred combination of design and operational configurations to provide heat removal from high-level waste tanks during Phase 1 waste feed delivery to prevent the waste temperature from exceeding tank safety requirement limits. An interim decision for the preferred method to remove the heat from the high-level waste tanks during waste feed delivery operations is presented herein.
Study on structure heat capacity of high-rise residences: (part 2) comparison by insulation methods
This paper follows the paper of Part 1. Here we examined Air-Conditioning loads (hereinafter referred to as AC loads) impact in several deferent cases of insulation methods in interior of super high-rise residences by using the dynamic simulation software ... Keywords: AC load, heat capacity, heat insulation method, high-rise residences, simulation
Yupeng Wang; Hiroatsu Fukuda; Akihiro Mitsumoto; Akihito Ozaki; Yuko Kuma
High Rayleigh number thermal convection in volumetrically heated spherical shells
parameterizations for the average temperature of the shell and for the temperature jump across the thermal boundary properties, cores and overlying shells (e.g., silicate mantles or ice layers) of rocky planets and icy moons, including the rheology of the material, the presence of phase transitions, and the mode of heating
Tackley, Paul J.
High temperature thermographic measurements of laser heated silica
In situ spatial and temporal surface temperature profiles of CO{sub 2} laser-heated silica were obtained using a long wave infrared (LWIR) HgCdTe camera. Solutions to the linear diffusion equation with volumetric and surface heating are shown to describe the temperature evolution for a range of beam powers, over which the peak surface temperature scales linearly with power. These solutions were used with on-axis steady state and transient experimental temperatures to extract thermal diffusivity and conductivity for a variety of materials, including silica, spinel, sapphire, and lithium fluoride. Experimentally-derived thermal properties agreed well with reported values and, for silica, thermal conductivity and diffusivity are shown to be approximately independent of temperature between 300 and 2800K. While for silica our analysis based on a temperature independent thermal conductivity is shown to be accurate, for other materials studied this treatment yields effective thermal properties that represent reasonable approximations for laser heating. Implementation of a single-wavelength radiation measurement in the semi-transparent regime is generally discussed, and estimates of the apparent temperature deviation from the actual outer surface temperature are also presented. The experimental approach and the simple analysis presented yield surface temperature measurements that can be used to validate more complex physical models, help discriminate dominant heat transport mechanisms, and to predict temperature distribution and evolution during laser-based material processing.
Elhadj, S; Yang, S T; Matthews, M J; Cooke, D J; Bude, J D; Johnson, M; Feit, M; Draggoo, V; Bisson, S E
New England Gas Company - Residential and Commercial Energy Efficiency
New England Gas Company - Residential and Commercial Energy New England Gas Company - Residential and Commercial Energy Efficiency Rebate Programs New England Gas Company - Residential and Commercial Energy Efficiency Rebate Programs < Back Eligibility Commercial Fed. Government Local Government Nonprofit Residential State Government Savings Category Heating & Cooling Commercial Heating & Cooling Heating Home Weatherization Commercial Weatherization Heat Pumps Appliances & Electronics Water Heating Program Info State Massachusetts Program Type Utility Rebate Program Rebate Amount Residential Furnace: $300 - $450 Boilers: $1000 - $1500 Combined High Efficiency Boiler/Water Heater: $1,200 Heat Recovery Ventilator: $500 High Efficiency Indirect Water Heater: $400 Condensing Gas Water Heater: $500 High Efficiency On-Demand, Tankless Water Heater: $500 - $800
Required Materials Properties for High-Efficiency CIGS Modules: Preprint
This paper discusses material properties required for each CIGS device layer so that large-area CIGS modules can achieve efficiencies of >15%, substantially higher than the current state of the art.
Repins, I.; Glynn, S.; Duenow, J.; Coutts, T. J.; Metzger, W.; Contreras, M. A.
Electric co-heating in the ASHRAE standard method of test for thermal distribution efficiency: Test results on two New York State homes
Electric co-heating tests on two single-family homes with forced-air heating systems were carried out in March 1995. The goal of these tests was to evaluate procedures being considered for incorporation in a Standard Method of Test for thermal distribution system efficiency now being developed by ASHRAE. Thermal distribution systems are the ductwork, piping, or other means used to transport heat or cooling effect from the building equipment that produces this thermal energy to the spaces in which it is used. Furthering the project goal, the first objective of the tests was to evaluate electric co-heating as a means of measuring system efficiency. The second objective was to investigate procedures for obtaining the distribution efficiency, using system efficiency as a base. Distribution