conventional solar cells last and the solar cells were relatively inefficient. Conventional solar cells can easily convert 15 percent of the energy in sunlight into electricity; Konarka's cells only converted up to 8.3%, the highest that the National Renewable Energy Laboratory has recorded for organic photovoltaic cells. Flexible batteries Konarka owned the rights to an organic-based solar-recharging flexible battery technology. However, as of April 2007, Konarka had no plans to produce these commercially itself. Flexible batteries have thin-solar cells which are held inside a flexible gas barrier to prevent them from degrading when exposed to air. At just two grams in weight and just one millimetre thick, the flexible battery is small enough to be used in low-wattage gadgets - including flat smart cards and mobile phones. The potential for this type of product was seen as large, given that there was a growing demand for portable self-rechargeable power supplies. Production Dye-sensitized solar cells Konarka Technologies and Renewable Capital announced the licensing and joint development of Konarka's dye-sensitized solar cell technology for large-scale production, scaling to several hundred megawatts. Polymer-fullerene solar cells Konarka opened a commercial-scale factory, with the capacity to produce enough polymer-fullerene solar cells every year to generate one gigawatt of electricity, the equivalent of a large nuclear reactor. The company planned to gradually ramp up production at its new factory, reaching full capacity in two to three years. Patents Konarka was issued a number of United States patents relating to its photovoltaics research: 6706963, Jan 25, 2002, "Photovoltaic cell interconnection" 6858158, Jan 24, 2003, "Low temperature interconnection of nanoparticles" 6900382, Jan 24, 2003, "Gel electrolytes for dye sensitized solar cells" 6913713, Jan 24, 2003, "Photovoltaic fibers" 6924427, Jan 24, 2003, "Wire interconnects for fabricating interconnected photovoltaic cells 6933436, Apr 27, 2001, "Photovoltaic cell" 6949400, Jan 24, 2003, "Ultrasonic slitting of photovoltaic cells and modules" 7022910, Mar 24, 2003, "Photovoltaic cells utilizing mesh electrodes" 7071139, Dec 20, 2002, "Oxynitride compounds, methods of preparation, and uses thereof" 7186911, Jan 24, 2003, "Methods of scoring for fabricating interconnected photovoltaic cells" See also Fullerene Low cost solar cell Oerlikon Solar Organic electronics References External links Official website of Konarka Technologies, Inc. Konarka Claims 1GW in Organic PV Production Solar energy companies of the United States Dye-sensitized solar cells Organic solar cells Thin-film cell manufacturers Defunct technology companies based in Massachusetts Companies based in Lowell, Massachusetts Energy companies established in 2001 Renewable