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UWA	activated or non-activated lithium samples, which are consistent with the observation in the SDT Q600 measurements. The BET analysis at 77 K for both the pre-activated lithium sample and the produced lithium nitride were conducted to measure the surface areas. The surface area of pre-activated lithium was too small to be detected; the surface area of the produced lithium nitride was estimated to be 1.37 m2/g. Figure 5.6 The uptakes of nitrogen and methane on non-activated and pre-activated lithium samples at 60°C and at a pressure range of 0 to 100 kPa 5.3.4 SEM-EDS Characterisation The SEM images of the lithium sample as-received and after being exposed to air for 5 minutes are shown in Figure 5.7. The areas marked by the dotted circles in the two images confirmed that these two images were taken on the same location of the same lithium sample. Before exposed to air, the as-received lithium sample already contains some grains, as shown on the top and bottom parts of Figure 5.7 (a). The EDS results (covering the entire image area) gave an oxygen content of 85.9 wt %, which suggests that the main impurities on the surface of the as-received lithium sample were oxygen- contained impurities. Because the EDS detector was not able to detect the element of lithium, the content of elements reported excluded the evident presence of lithium. After being exposed to air for 5 minutes, more grains appeared on the sample surface, as shown prominently in the center area of Figure 5.7 (b). The oxygen content increased to 94.5 wt %, which suggests that the newly appeared grains mainly consisted of oxygen. No nitrogen element was detected by EDS, which indicate that no detectable lithium nitride had been formed. These observations are consistent with the reported 113
UWA	studies which stated that upon exposure to air, the resulting products formed on the surface of lithium metal would be LiOH, and not lithium nitride.[42, 44] Another important observation is that the grains which have been previously existed remained in essentially the same morphology before and after being exposed to air for 5 minutes. It suggests that such areas are relatively inert to air, which explains the inert nature of as received lithium sample to dry nitrogen at moderate temperatures. In comparison, the surrounding area of the newly formed grains is expected to contain active edge sites which can initiate the reaction of activated lithium with dry nitrogen. Figure 5.7 SEM and EDS of (a) as received lithium sample and (b) air-exposed lithium sample. The circled area confirms the SEM pictures are taken at the same position of the lithium metal. The oxygen content on the surface of lithium increased from 85.9 wt% to 94.5 wt% after exposure to air for 5 minutes. The surface morphologies of the pre-activated lithium sample and the produced lithium nitride are shown in Figure 5.8. Compared to the surface of pre-activated lithium, the surface of the produced lithium nitride has apparent cracks (marked with red squares). This is consistent with the results of surface area measurement using ASAP2020, which state that lithium nitride has higher surface area than lithium metal. Such cracks are believed to provide channels for the diffusion of nitrogen. The formation of such cracks is due to the low Pilling-Bedworth ratio (PB ratio) of lithium nitride over lithium (Pilling-Bedworth ratio = 0.64).[42] Here, the Pilling–Bedworth Ratio stands for the ratio of the volume of the elementary cell of lithium nitride to the volume of the elementary cell of lithium metal, 114
UWA	5.3.5 Discussion The observed difference in the uptakes of nitrogen on non-activated and pre-activated lithium metal prompted us to consider the role of water moisture in the reaction. It has been reported that freshly made lithium with active edge sites can react with dry nitrogen under moderate temperatures.[42, 185, 186] However, freshly made metal is too expensive to produce in-situ and impractical to store. Additionally, the active edge sites on freshly make lithium is easily lost through reactions with various species during storage. As a result, it is not practical to use freshly made lithium for nitridation reaction in large-scale applications. When the moisture is present in the nitrogen stream or when lithium has been pre-activated in moisture, the lithium surface is covered by a layer of “black coating”. [41, 42] “The black coating” is the amorphous form of lithium metal covered by a thin and transparent coating of lithium hydroxide.[42] When exposed to dry nitrogen, the amorphous lithium metal regains the ability to react with the dry nitrogen at low temperatures. The role of water moisture is to create an amorphous layer on the surface of lithium metal, which produces active edges sites.[41] The presence of water moisture disrupts the normal body-centered cubic structure of lithium metal, and yields to additional active edge sites due to the reaction between lithium and water. Such active edge sites are similar to the ones on the freshly made lithium metal, and they are the key for the initiation of the reaction of lithium metal. Continuous flow while exposing the lithium metal to an atmosphere of water moisture is also crucial to stimulate the initiation process. In the synchrotron study, the surface of the lithium in the flow through cell was exposed to more moisture compared to the one in the static cell, resulting in a higher number of active edge sites, which led to the faster initiation time. The role of active edge sites was also confirmed with the results from the other two characterization methods: TGA and ASAP2020. The results from TGA experiments confirmed the importance of active edge sites, as the non-activated lithium, which is lacking active edge sites, remained inert to dry nitrogen within the experimental time scale (~200 mins) at the set temperature of 60 °C, while the pre-activated lithium samples, having freshly revealed additional active sites, reacted with dry nitrogen readily and take in nitrogen gas to its theoretical uptake value. Similarly, the results from ASAP 2020 showed that while the pre-activated lihium sample uptook nitrogen, there was a negligible amount of nitrogen uptaken by the non- activated lithium sample. A simplified proposed schematic of the initiation pathways for the reaction of lithium with dry nitrogen (containing less than 2 ppm water moisture) is shown in Figure 5.9. 116
UWA	Figure 5.9 Simplified schematic of the reaction routes of lithium with dry nitrogen. Route A has been proposed in the literature;[185, 186] Routes B and C are based on the tests conducted with the TGA and ASAP2020 in this work Once the reaction of lithium with dry nitrogen is initiated, the reaction becomes self-sustained and gives a sigmoid curve of weight growth with time.[42, 183, 185] The results from the experiments on the TGA shown in Figure 5.4 show that the rate of reaction ramped up rapidly upon the completion of the initiation phase, and then slowed down gradually, which agreed well with the reported results. [42, 183, 185] As the reaction proceeds, the crystals of lithium metal are constantly being disrupted and active edge sites were continuously generated on the surface of the lithium metal. Such active edge sites on the disrupted lithium crystal were similar to the ones on freshly made lithium and also those created by water moisture, which makes reaction self-sustained and thus the water moisture is not necessary beyond initiation. At the same time, cracks are forming on the newly produced lithium nitride layer due to the Pilling- Bedworth ratio of lithium nitride of 0.64 (less than 1),[41, 42], which is confirmed by the observation in Figure 5.8. The geometrical diameters of the produced lithium nitride particle and the original lithium particle remain essentially the same, as shown in Table 5.1, which indicates the void fraction of the produced lithium nitride is around 36 %, as calculated by Equation 5.13. The cracks are large enough to provide channels for nitrogen to diffuse through.[42, 185, 186] 117
UWA	Table 5.1 The geometrical diameters and the density of the original lithium sample and the produced lithium nitride. (The geometrical diameters were measured by a caliper with an uncertainty of 0.01 mm) Lithium Lithium Nitride Length (mm) 3.75 3.74 Diameter (mm) 2.24 2.24 Density (g/cm3) 0.534 1.27 Void Fraction - 36% Equation 5.13 𝑚𝑚𝐿𝐿𝑁𝑁 𝑚𝑚𝐿𝐿𝑁𝑁3𝑁𝑁 �⍴𝐿𝐿𝑁𝑁− �⍴𝐿𝐿𝑁𝑁3𝑁𝑁 𝑉𝑉𝑐𝑐𝑃𝑃𝑑𝑑 𝐹𝐹𝑟𝑟𝑎𝑎𝑐𝑐𝑡𝑡𝑃𝑃𝑐𝑐𝑛𝑛 = 𝑚𝑚𝐿𝐿𝑁𝑁 �⍴𝐿𝐿𝑁𝑁 In summary, through an activation method, commercially available lithium metal can be activated to react with dry nitrogen (water content less than 2 ppm) at moderate temperatures. Once activated, the reaction of lithium with dry nitrogen becomes self-sustained, producing a substantial uptake of nitrogen. 5.4 Separation of Nitrogen from A Binary Gas Mixture of Nitrogen and Methane Lithium Lithium performance for the separation of nitrogen from a binary gas mixture of nitrogen and methane was studied using a dynamic column breakthrough (DCB) apparatus. The tests were conducted under the following conditions: 10% nitrogen and 90% methane at 60 °C, the total pressure of 884 kPa, the total flow rate of 20 sccm ( ) and lithium sample mass of 0.80 g. 𝑓𝑓𝑁𝑁2 = 2 sccm; 𝑓𝑓𝑇𝑇𝐶𝐶4 = 18 sccm 118
UWA	Figure 5.10 Breakthrough curve of nitrogen (10 mol %) and methane (90 mol %) feed mixture passing through a lithium loaded column with, the total flow rate of 20 sccm and lithium sample mass of 0.80 g The breakthrough curves of nitrogen, methane and helium are shown in Figure 5.10. The nitrogen mole fraction in the effluent gas was significantly reduced from the loading composition of 10% to a low level of 2% for around 100 mins, and then slowly increased back to 10% after around 300 minutes. Meanwhile, methane broke through the lithium column immediately after the gas mixture was switched to feed the lithium column. The methane mole fraction reached 98% from the original 90% and was maintained at this high level for around 100 mins before decreasing slowly back to 90% at around 300 mins. The uptakes of nitrogen and methane are calculated by Equation 5.12: the uptake of nitrogen reached 19 mmol/g which is consistent with the uptake of nitrogen calculated by the weight change measured before and after the reaction; the uptake of methane was zero which was consistent with the results from the TGA and ASAP2020. In conclusion, this test of binary gas mixture breakthrough shows that lithium metal has substantial potential to separate nitrogen effectively from gas mixtures of nitrogen and methane. 5.5 Regeneration of Lithium from Lithium Nitride 5.5.1 Regeneration of Lithium by Thermal Decomposition of Lithium Nitride 5.5.1.1 Thermal Decomposition Calculation In principle, lithium metal could be regenerated from lithium nitride by thermal decomposition through a combination of pressure and temperature swing process, although the conditions of the regeneration are expected to be harsher than those normally applied in industry. The chemical 119
UWA	equation for the decomposition of lithium nitride to lithium and nitrogen is shown in Equation 5.14. The conditions for such thermal decomposition were investigated by both a thermodynamic calculation and an experimental exploration described in this section. The change of Gibbs free energy of a certain reaction is the thermodynamic indicator to evaluate this reaction`s feasibility and spontaneity: when , the reaction is spontaneous; when , the reaction is non-spontaneous. By definition, t ∆h 𝐺𝐺e𝑁𝑁 c <ha 0nge in the Gibbs free energy of the sy ∆s 𝐺𝐺te𝑁𝑁m > e 0quals to the change in the enthalpy of the system minus the change in the product of the temperature times the entropy of the system, shown in Equation 5.19. The enthalpy change of the system is the sum of the formation enthalpy of the products minus those of reactants, shown in Equation 5.17. The entropy change of the system is the sum of the formation entropy of the products minus those of the reactants, shown in Equation 5.18. The formation enthalpy and formation entropy of the studied chemicals are functions of temperature, and the thermochemical data and the calculation equation are shown in Table 5.2, Equation 5.15 and Equation 5.16. The predicted change of Gibbs energy of the thermal decomposition of lithium nitride as a function of temperature is plotted in Figure 5.11. It is clear from Figure 5.11 that only when the temperature is higher than 1250 °C, will the thermal decomposition of lithium nitride become spontaneous and produce 100 kPa nitrogen and lithium vapor. This extremely high temperature is not suitable to be employed in the natural gas processing plant. 120
UWA	Figure 5.11 Predicted Gibbs energy for the thermal decomposition of lithium nitride as a function of temperature. The calculation suggests that only when the temperature is above 1250 °C, will the thermal decomposition of lithium nitride become spontaneous. Regeneration conditions at low temperatures are preferred and could potentially be achieved by reducing the partial pressure of nitrogen and lithium vapor. To obtain the relationship between the change of Gibbs energy and the reaction equilibrium constant (K), the definition of Gibbs free energy change of reaction as shown in Equation 5.20 below is used. Equation 5.20 0 ∆𝐺𝐺𝑁𝑁 = ∆𝐺𝐺 +𝑅𝑅𝐴𝐴𝑅𝑅𝑛𝑛(𝐾𝐾) When , the reaction is at its equilibrium state. The change of Gibbs energy at standard condit i ∆on 𝐺𝐺s𝑁𝑁 i =s th 0en a function of the reaction equilibrium constant, as shown in Equation 5.21 below. Equation 5.21 0 𝐺𝐺 = −𝑅𝑅𝐴𝐴𝑅𝑅𝑛𝑛(𝐾𝐾) Assuming the activity coefficients for nitrogen and lithium are unity and lithium nitride stays in the solid state during the decomposition, the reaction equilibrium constant ( ) is correlated to the partial pressure of nitrogen and lithium vapor, as shown in Equation 5.22 𝐾𝐾 Equation 5.22 6 𝑃𝑃𝑁𝑁2 ∗𝑃𝑃𝐿𝐿𝑁𝑁 6 K = 0 = 𝑃𝑃𝑁𝑁2 ∗𝑃𝑃𝐿𝐿𝑁𝑁 𝑃𝑃𝐿𝐿𝑁𝑁3𝑁𝑁 Next, the partial equilibrium pressure of nitrogen and lithium vapor are assumed to follow the stoichiometric relation, as shown in Equation 5.23 below. 122
UWA	Equation 5.23 𝑃𝑃𝐿𝐿𝑁𝑁 = 6𝑃𝑃𝑁𝑁2 Finally, by combining Equation 5.21, Equation 5.22 and Equation 5.23, the partial pressure of nitrogen can be expressed as a function of temperature, as shown in Equation 5.24, Equation 5.24 0 ∆𝐺𝐺 𝑃𝑃𝑁𝑁2 = (𝑒𝑒− 𝑅𝑅𝑇𝑇 /(66 ))^7 Therefore, the temperature for the spontaneous thermal decomposition of lithium nitride as a function of the partial pressure of nitrogen can be estimated, as shown in Figure 5.12. Also shown is another thermodynamic calculation reported by Lian et al., 2009 and two sets of experimental data reported by Hitoshi et al., (1980) and Yonco et al., (1975).[192, 288, 289], Lian et al., (2009) also validated their thermodynamic calculation with one set of experimental data at 382 °C and 10-3 Pa[192]. Yonco et al.`s data showed the biggest deviation from the calculation shown here, which might be due to their misuse of total pressure (which equals the sum of the partial pressure of nitrogen and partial pressure of lithium) as the partial pressure of nitrogen. The other two reported data sets from Hitoshi et al. and Lian et al. match the calculation reasonably well. The calculation shown in Figure 5.12 indicates that it is possible to decompose lithium nitride at relatively low temperatures by decreasing the partial pressure of nitrogen. For example, the temperature of the decomposition of lithium nitride can be potentially reduced to 600 °C if the partial pressure of nitrogen can be reduced to 1.2 Pa. 123
UWA	5.5.1.2 Thermal Decomposition Experiments The feasibility of the regeneration of lithium metal from thermal decomposition of lithium nitride was experimentally investigated to confirm the prediction of the above calculation. Three sets of experiments were performed using the TGA Q50. In the first two sets of experiments, ceramic crucibles were chosen with a capacity of 90 μL, which is intended for the operation from ambient temperature to 1500 °C. The results are shown in Figure 5.14 (a) and (b). The temperature of the lithium nitride sample was increased to 500 °C at a ramp rate of 30 °C/min and then maintained at this temperature for 20 minutes. Helium with a nominal concentration of 99.999 vol. % (N < 4 ppm; 2 H O < 2 ppm) was used as the purge gas and the flow rate was set at 100 mL/min. The total pressure 2 of the helium purge gas was adjusted to 138 kPa, so the partial pressure of nitrogen was estimated to be 0.55 Pa. Theoretically, full decomposition of lithium nitride would lead to a decrease in the sample weight by 40 %, assuming that the released nitrogen was purged out and the produced lithium stayed in the crucible. However, within the duration of the experiment, the weight of lithium nitride sample essentially remained the same, indicating that no lithium nitride has decomposed. In a second experiment, as shown in Figure 5.14 (b), the furnace temperature was first increased to 500 °C and maintained at this temperature for 30 minutes, before being further increased with a target of 800 °C at a ramp rate of 30 °C/min. The helium purge gas was set to the same conditions with the previous experiment. The sample showed a 20% weight loss between temperatures of 600 °C and 800 °C, suggesting that the lithium nitride started to decompose at 600 °C: the 20% weight loss was equivalent to the decomposition of 20% of the lithium nitride. The decomposition temperature (600 °C) and the partial pressure of nitrogen (0.55 Pa) were consistent with the calculated relationship between decomposition temperature and pressure. However, cracking of the ceramic sample crucible in the following 20 mins forced the experiment to conclude prematurely. 125
UWA	(a) Ramp 30 °C/min; 500 °C; Pnitrogen < 0.55 Pa (b) Ramp 30 °C/min; 500 °C <T<800°C; Pnitrogen<0.55 Pa Figure 5.14 Thermal decomposition tests of lithium nitride on the thermogravimetric analyzer (TGA) with the ceramic crucible. The blue line corresponds to the weight change of the lithium nitride sample, shown on the left vertical axis. The red line corresponds to the temperature profile, shown on the right vertical axis. (a) Experiment 1 with a temperature target of 500 °C at a ramp rate of temperature of 30 °C/min; the partial pressure of nitrogen is estimated to be smaller than 0.55 Pa. (b) Experiment 2 with an initial temperature target of 500 °C at a ramp rate of 30 °C/min, and a second temperature target of 800 °C at the same ramp rate; the partial pressure of nitrogen is estimated to be smaller than 0.55 Pa. In a third experiment, a platinum crucible with a capacity of 100 μL, which is intended for operation from ambient temperature to 1000 °C, was used to try to overcome the cracking issue encountered with the ceramic crucible. In this test, the temperature of the lithium nitride sample was increased to 800 °C at a ramp rate of 5 °C/min and the helium purge gas was set to the same conditions with the 126
UWA	previous experiments. From the result shown in Figure 5.15, a 5% weight increase was observed, which might be due to side reactions of lithium nitride with impurities in the purge gas, such as moisture or carbon dioxide. When the temperature reached 800 °C, the weight of the sample dropped sharply and then increased again. The bottom of the platinum crucible was deformed and observed to be “melted”, as shown in Figure 5.16. This was most likely due to the formation of Li-Pt alloy at elevated temperatures.[295-298] While lithium metal might have been regenerated from lithium nitride at 800 °C, it is highly reactive at elevated temperature and would immediately react with any surrounding material, producing an alloy as a product of its reaction with the platinum crucible. Therefore, although lithium can be thermally regenerated from lithium nitride, a specially designed material is required to be able to handle the produced high-temperature lithium vapor. In conclusion, considering the harsh conditions required and the high reactivity of lithium reactivity toward conventional materials at elevated temperatures, the thermal decomposition of lithium nitride to recycle lithium using the described approach is concluded to be not feasible. Figure 5.15 Thermal decomposition of lithium nitride on the thermogravimetric analyzer (TGA) with the platinum crucible. The green line corresponds to the weight change of the lithium nitride sample, shown on the left vertical axis. The blue line corresponds to the temperature profile, shown on the right vertical axis. The target temperature was 800 °C at a ramp rate of 5 °C/min; the partial pressure of nitrogen was estimated to be smaller than 0.55 Pa. 127
UWA	Figure 5.16 Platinum crucible after the thermal decomposition of lithium nitride experiment at 800 °C. The bottom of the platinum crucible was “melted” by the produced lithium vapor, which was due to the formation of Li-Pt alloy. 5.5.2 Regeneration of Lithium by A Chemical Loop Lithium metal might alternatively be recycled from lithium nitride in a closed loop with a three-step regeneration process as shown in Figure 5.17. Step 1: The lithium nitride is first converted to LiOH by bringing it into contact with water. This step also produces ammonia, which is intrinsically a valuable material. Step 2: The resultant LiOH from Step 1 is converted to LiCl by adding hydrochloric acid. Step 3: The LiCl from Step 2 is converted to lithium metal by the mature commercial process of LiCl electrolysis[299-302], while the side product of chlorine gas can be recycled to form hydrochloric acid. Figure 5.17 Lithium recycle loop for the capture of nitrogen and production of NH 3 A brief economic analysis of the regeneration loop is given for the following case study: assuming the requirement is to remove nitrogen from a gas mixture with composition of 10 mol% nitrogen + 90 mol% methane to meet the specification for LNG (1 mol. % N + 99 mol. % CH ), and this LNG train 2 4 produces 5 million tonnes of LNG per annum. Based on the above assumptions, the amount of nitrogen which needs to be removed from the feed to be able to meet the LNG specification is 99 tonnes/hr. Subsequently, the required amount of lithium is 149 tonnes/hr, given that the lithium reacts with nitrogen according to the lithium/nitrogen reaction stoichiometry. To ensure continuous processing of the feed gas, three adsorption towers containing 128
UWA	the lithium would need to be used, where each of these towers would be used for 3 hours for the feed processing step and 6 hours for the regeneration step. Hence, each tower in the adsorption process would require 446 tonnes of lithium, assuming that the reaction kinetics are sufficiently fast. Therefore, the required initial one-off purchase of lithium metal would be 1338 tonnes. As the unit price of lithium metal is USD $110,000/tonne (Industrial grade), the total cost of the lithium required would be USD 147 million – assuming that the lithium could be fully recovered so that no further lithium metal purchase is required. Step 1 involves the conversion of Li N to LiOH. This conversion requires an additional reactant of water 3 and produces a side product ammonia, which has an economical value. The water required might be sourced by recycling the water produced in the natural gas production process, and therefore its cost could be considered as negligible. At the same time, the yearly production of 1.05 million tonnes of ammonia could be sold with a unit price of USD 400/tonne, producing an annual revenue of USD 421 million. In Step 2, the LiOH is converted to LiCl by adding HCl acid. As the HCl could be formed from the reaction of water with the chlorine gas produced from the electrolysis of LiCl, its cost could be considered as negligible. In Step 3, the LiCl produced in Step 2 will go through an electrolysis process to recycle the lithium metal. This electrolysis is a mature commercial process for extracting lithium metal from lithium compounds and energy consumption for the best performing process is about 8 kWh/kg. If the electricity is generated from a methane gas turbine, then the unit electricity price could be about USD 0.033/k Wh, which can be converted to USD 1.155/kg ($1155/tonne) of lithium produced. The total amount of lithium that needs to be electrolyzed each year is about 1.3 million tonnes. Therefore, the total cost of regenerating the lithium nitride to lithium metal is USD 344 million. When this total cost is offset against the revenue generated by the ammonia production, the process of removing nitrogen could make a profit of USD 88 per tonne of nitrogen removed. 5.6 Conclusion The reaction of lithium with dry nitrogen (H O < 2 ppm) under moderate temperatures has been 2 studied by TGA, ASAP2020 and synchrotron XRD. The mechanism of this reaction under moderate temperatures can be summarized by the following two points: (1) The reaction of lithium metal with dry nitrogen (moisture < 2 ppm) is initiated by active edge sites on the lithium metal. Such active edge sites can be either found on freshly made lithium metal or on commercially available lithium metal that has been activated by water moisture; (2) Once the reaction is initiated, it becomes self-sustained. 129
UWA	Active edge sites on lithium metal are continuously created through the reaction with nitrogen. The diffusion of nitrogen to the interface of lithium and lithium nitride occurs through the cracks in the layer of produced lithium nitride. A viable feasible and effective activation method for lithium metal toward the reaction with dry nitrogen was developed and demonstrated in this work. A case study of the separation of nitrogen from a binary gas mixture by lithium metal has been studied using the proposed activation method with a custom built apparatus. The lithium metal shows significant advantages compared to the normal adsorbents. First of all, the uptake of nitrogen on lithium metal consistently reached its theoretical value of 24 mmol/g, which is an order of magnitude higher than that of the best-reported nitrogen selective adsorbents. Moreover, as lithium metal remains inert to methane under the tested condition, it has a very large selectivity for nitrogen over methane, allowing for almost 100% methane recovery. Two approaches to the regeneration of lithium metal from lithium nitride have been considered in this chapter. Firstly, it would be ideal to regenerate lithium in-situ by a temperature and pressure swing from lithium nitride, analogous to the conventional temperature/pressure swing adsorption process. However, both the thermodynamic calculation and experimental results show that this approach is not feasible due to the extremely harsh conditions required for the thermal decomposition of lithium nitride. Such harsh conditions include but are not limited to high operation temperature, low nitrogen partial pressure and the need for specially designed furnace/tower material for handling high-temperature lithium. The second approach toward regeneration was using a closed chemical loop, which appears to be both technically and economically feasible. Each step of this loop can be handled by an industrial process that has already been well-established. A high-level economic analysis indicates that this chemical loop could potentially both recycle lithium from lithium nitride and make a profit of USD 88 per tonne of nitrogen from the conversion of nitrogen to ammonia. 130
UWA	Chapter 6: Conclusion and Future Work 6.1 Conclusion Natural gas is going to play a more important role in the worldwide energy market due to its relatively low emissions to the environment compared to oil and coal. It will serve as the bridging energy before the renewable energy technologies become mature and economically competitive. However, advanced separation technologies are required to upgrade raw natural gas to meet transportation and sale requirements. Nitrogen is one of the inherent impurities in raw natural gas and is considered to be the hardest impurity to remove efficiently and economically due to its similar physical properties to the main component of natural gas – methane. The current approach of removing nitrogen from natural gas is to liquefy nitrogen and methane together, and then separate the liquefied mixture by cryogenic distillation utilizing the difference in their volatility. Such nitrogen rejection units are energy- intensive to run because of the low boiling points of nitrogen (-195.8 °C) and methane (-161.5 °C). Technologies that can separate nitrogen from methane under moderate conditions are highly desired. A key contribution of this work has been to critically analyse the physical and chemical properties of nitrogen and methane, to review the conventional separation technologies that are mainly based on the difference in the physical properties of nitrogen and methane, and to assess emerging separation technologies that are mainly based on the difference in the chemical properties of nitrogen and methane. The adsorption process is one of the most attractive conventional separation processes for removing nitrogen from methane. Adsorption equilibria and kinetics are the two most crucial sets of properties to simulate and design an adsorption-based gas separation process. However, the availability of consistent kinetic data for each gas on various adsorbents is limited in literature, which leads to large uncertainties when using such data in process design. Motivated by this, the adsorption equilibria and kinetics data of nitrogen and methane on four commercial adsorbents are studied experimentally in this work using a commercial volumetric system (T = 273 and 303 K; P = 5 to 120 kPa). Two key elements were addressed: first, the dynamic uptake data acquired were corrected for the effects of gas expansion, which was done by calibrating the system response with helium to determine the initial condition; Second, a non-isothermal Fickian Diffusion (FD) model was used to analyse the kinetic data, which was able to describe the dynamic data with a deviation of only 1% for all the studied cases, compared to the commonly used isothermal linear driving force model with a relative root mean square deviation of 10%. 131
UWA	On MSC-3K 172 and zeolite 4A, a weak pressure dependence was observed for the sorption rate. On Norit RB3 and zeolite 13X, no pressure dependence was observed for the sorption rate. A clear temperature dependence was observed for all four adsorbents studied, and the Arrhenius type activation energies were all around (10 to 20) kJ⋅mol-1. Both Norit RB 3 and Zeolite 13X showed fast but similar kinetics for nitrogen and methane, and thus any separation of this gas mixture using these two adsorbents could only utilize their equilibrium selectivity, which was too small to be industrially feasible. Zeolite 4A and MSC-3K 172 show sufficiently faster uptake of nitrogen than that of methane, although they are still methane-selective at equilibrium. The kinetic selectivity of nitrogen over methane on Zeolite 4A and MSC-3K 172 are still moderate (1.4 to 2.2) compared to the reported best adsorbents such as Sr-UPRM-5 (25.42) or Sr-ETS-4 (21.62). However, the inexpensive price and the ease of availability of these two adsorbents play a huge contribution in giving them the potential to be scaled up for industrial application, particularly, with novel process design, such as dual-reflux pressure swing adsorption.[303-305] An absorption process operating at ambient temperature was proposed in this work as an alternative technology, which could be analogous to the process used to separate carbon dioxide from natural gas with an aqueous solution of amine. An aqueous solution of transition metal complexes (TMC) which can selectively absorb nitrogen is the key to differentiate this proposed absorption process from the conventional methane-selective absorption processes which use physical solvents. Mimicking nitrogenase enzymes in biological nitrogen fixation, TMCs have been studied intensively to fix nitrogen from the atmosphere and then to convert nitrogen to ammonia. The TMCs required to separate nitrogen from methane is relatively easier to study compared to those in the applications of fixation and conversion of nitrogen. The reason is that such TMCs only need to bond nitrogen molecules without cleaving the extremely strong triple bonds in nitrogen molecules which is the most challenging step in the conversion of nitrogen to ammonia. In this work, fourteen TMC systems have been studied to absorb nitrogen. Three Ru-based TMC systems showed the abilities to absorb nitrogen, with the best one being the K[RuII(EDTA)] aqueous solution, which gave eight times the higher capacity of nitrogen than that of water. The preparation of this TMC was done according to previously reported methods of synthesis.[244, 265] The structure of this TMC was confirmed by elemental analysis and infrared spectroscopy (IR). The absorption equilibria and associated uncertainties of nitrogen in this TMC solution were measured on a custom designed solubility apparatus under various conditions. The apparatus can measure the adoption equilibria ranging from 1E-3 to 1 mol/L, with a temperature ranging from 20 °C to 40 °C at pressures ranging from 0 kPa to 5,000 kPa. When the molar concentration of this Ru-based TMC was 0.1M, this 132
UWA	TMC solution showed an overall capacity of nitrogen of 6.11E-02 mol/L and selectivity of nitrogen over methane of 2 at ~30 °C and ~3000 kPa. The specific capacities of nitrogen per RuII were estimated to remain essentially the same at different TMC concentrations (0.1M and 0.25M). A desorption hysteresis was observed which is typical for chemisorption and a combination of pressure swing and temperature swing is required to generate the TMC solution. The enthalpy of absorption of nitrogen in this solution is estimated to be 30-60 kJ/mol N which varied with the loading of nitrogen. These 2 enthalpies of absorption of nitrogen are relatively low compared to the enthalpy of absorption of CO 2 in an aqueous solution of amine (around 100kJ/mol CO ), which implies that only moderate amount 2 of energy would be required to regenerate this solution of TMC. Overall, this work demonstrates the potential of using TMC solutions to absorb nitrogen from methane under moderate conditions. The high cost and the limited annual production of ruthenium impede the application of this Ru-based TMC solution on a large scale. However, this can be overcome by replacing ruthenium with more abundant transition metals, such as iron and vanadium. Several TMC candidates have been tested as well, but none of them can absorb nitrogen. Therefore, a fundamental understanding of the binding mechanism between nitrogen and TMCs and systematic screening of TMCs consisting of an abundant transition metal and low-cost ligands are highly desired. Lastly, a novel process using lithium to separate nitrogen from methane was proposed and investigated. Lithium metal has been studied to remove nitrogen from crude argon, but has not been applied to the separation of nitrogen from natural gas. The main challenge of adapting the lithium metal-based separation process to a natural gas processing plant has been to make the reaction of lithium with dry nitrogen happen at moderate temperatures. However, the mechanism of this reaction under moderate conditions remained a mystery. In this study, the reaction of lithium with dry nitrogen (water content < 2 ppm) was intensively studied at moderate temperatures by various methods, including TGA, ASAP2020, synchrotron XRD and a custom-built flow-through apparatus. Furthermore, two approaches of regenerating of lithium from lithium nitride were proposed and critically analysed. There are three contributions of this study to the separation of nitrogen from natural gas by lithium metal. First, a mechanism for the reaction of lithium with dry nitrogen was proposed and verified. Active edge sites on the lithium metal are mandatory to initiate the reaction. Such high free energy sites can be found either on freshly made lithium or on lithium metal that has been activated by water moisture. The reaction becomes self-sustained once initiated: the active edge sites are continuously created as the reaction proceeds; the cracks in the lithium nitride layer provides the channels for the diffusion of nitrogen molecules. Second of all, a simple and efficient method was discovered to activate contaminated lithium metal toward the reaction with nitrogen at moderate temperatures. 133
UWA	After exposure to water moisture, the contaminated lithium regains the ability to react with dry nitrogen. The results from TGA and ASAP2020 show that the uptake of nitrogen on activated lithium can be as high as the theoretical value of 24 mmol/g at temperatures from 30 to 90 °C and pressures from 30 to 100 kPa. Third, the performance of lithium metal to separate nitrogen from a binary gas mixture of nitrogen and methane was demonstrated on a flow-through apparatus. The results show that lithium metal can reduce the content of nitrogen from 10% to 2% in the binary gas mixture. Overall, lithium metal shows two significant advantages to capture nitrogen: (1) the uptake of nitrogen on lithium metal can reach the theoretical capacity of 24 mmol N /g, one order of magnitude higher 2 than the best reported nitrogen-selective adsorbents; (2) the selectivity of nitrogen over methane can be infinitely large due to the inert nature of lithium to methane. Two methods of recycling lithium from lithium nitride were discussed in this work as well: (1) regeneration of lithium by thermal decomposition of lithium nitride; (2) regeneration of lithium by a chemical loop. The thermal decomposition of lithium nitride was found to be unfeasible given that high operation temperatures, high purity purge gas, and specially designed furnace/tower material would be needed for handling high-temperature lithium. The chemical loop method is theoretically feasible, given that each step is already a part of mature industrial processes. Furthermore, the economic estimation showed that when taking the by-product of ammonia into account, a profit of USD 88 per tonne of nitrogen can be made through this process. Therefore, regeneration of lithium from lithium nitride by the chemical loop is both technically and economically feasible. 6.2 Recommendations and Future Work Among the physical properties of nitrogen and methane, the difference in the kinetic diameter is the most promising one in which to develop new separation processes that can separate nitrogen from methane as an alternative to distillation. Such new and alternative separation processes include membrane and adsorption processes. Inorganic membranes, such as zeolite, MOF or carbon molecular sieve membranes, can distinguish this physical property difference effectively. However, the major challenge for them remains the scale-up ability. Most of the inorganic membranes suffer poor mechanical properties and engineering problems. For adsorption process, Zeolite 4A and MSC-3K 172 remains the best candidates when taking availability and cost into account. Effective separation performance can be achieved through novel process design, such as dual-reflux pressure swing process (DRPSA). More effects should be focused on the optimization of the light/heavy reflux rate, feed time and purge pressure.[303-305] 134
UWA	The most promising chemical property of nitrogen that can be utilized to separate nitrogen from methane is its role as a weak ligand coordinating to the TMC. For adsorption, recent research has shown that unsaturated Cr sites on MIL-100 and MIL-101 (MOFs)[140, 141] and unsaturated Ni or Cu sites on ion-exchanged MFI and ZSM (zeolites)[306] can selectively bind nitrogen. The overall equilibria favour nitrogen over methane at relatively low pressure due to the high affinity of nitrogen to the unsaturated transition metal sites, although it becomes methane selective when the pressure increases. One way to overcome this problem is to design a material that combines the molecular sieve effect (with pore size locating between 3.68 and 3.8 A) and the nitrogen coordinating effect (with unsaturated transition metal sites for nitrogen bonding). There is no reported study focusing on this approach yet. For membrane process, one approach could be integrating nitrogen binding chemicals, either porous or non-porous TMCs, into the polymer matrix to make mixed matrix membrane, which has the advantage of being easy to scale up. Another approach is to make an inorganic membrane composed of the nitrogen binding porous zeolites or MOFs, but the processibility of such inorganic membranes could be challenging. Lastly, the lithium-based process is a promising process for the separation of nitrogen from natural gas. The activated lithium metal shows considerably high uptake of nitrogen and gives a significant large selectivity of nitrogen over methane. The regeneration of lithium from the produced lithium nitride by a proposed chemical loop is technically and economically feasible, proved by critical analyses. Future efforts can be focused on the process simulation and more detailed analysis of the feasibility of this process. Furthermore, the in-situ regeneration of lithium can be potentially achieved by direct electrolysis of the produced lithium nitride. Lithium nitride has small electrolysis potential of 4.6 eV and it is a good electron conductor, all of which make it theoretically feasible to recycle lithium metal from the electrolysis of lithium nitride.[43] So far, there have only been limited data available on the electrolysis of lithium nitride, hence new efforts in this electrolytic approach to recycling lithium from lithium nitride could prove to be highly beneficial for the advancements in this field. 135
UWA	• Strong reducing agent: Mg REQUIREMENTS • No partner needed Standard Operation Procedure Step 1 Prepare RuCl /water – solution (I) 3 1. Dissolve 1.0372 g (0.005 mol) RuCl into 20mL DI water in a centrifuge tube and swirl the 3 tube with hands to speed up the dissolving of RuCl until no apparent solid particles could be 3 seen. Step 2 Prepare Na EDTA/water – solution (II) 3 1 Dissolve 2.2127 g (0.005 mol) Na [EDTA] into 10mL DI water in a 100 mL glass beaker 3 2 Gently warm up the solution on a hot plate to 140 °C until the solid dissolves to give a clear solution. In this process, no magnetic stirrer rod is needed, just use hands to swirl the glass beaker on the hot plate. Step 3 Prepare RuIII[EDTA]/water – solution (III) 1. After the Na EDTA/water solution turns transparent, turn up the heating control of the hot 3 plate so that the solution maintains a simmering state. 2. Then, slowly add the RuCl /water solution (the 20mL RuCl solution in 2 minutes) to the 3 3 Na EDTA/water solution while swirling the beaker with Na EDTA/water solution. If there is a 3 3 significant amount of RuCl left in the centrifuge tube, another 20 mL of DI water can be 3 added to the tube to rinse out the leftover RuCl and add this RuCl solution to the 3 3 Na EDTA/water solution while swirling the beaker. 3 Step 4 RuIII[EDTA] powder 1. Turn up/down the hot plate temperature to keep the resulting solution at simmering state until the solution turns to a slurry state, and turns off the heating on the hot plate and leave the beaker to cool down naturally on the hot plate. 2. After the product cools down, collect the precipitate and dry it with suction filtration. 3. Wash the product thoroughly with ice water until it is free of RuIII ions. 138
UWA	Figure A.3 Synthesized RuII[EDTA]- aqueous solution. The preparation method of this solution is described above and the solution is stored in glove-box. Infrared Spectroscopy (IR) K[Ru(EDTA)] was synthesized according to the method reported in the literature [267, 311, 312] and was characterized with an infrared spectrometer to confirm its structure. Spectrum One FT-IR Spectrometer (PerkinElmer) equipped with a universal attenuated total reflection (ATR) sampler and a deuterated triglycine sulfate (DTGS) detector was used to record the IR spectra of both pure K [EDTA] 3 and the synthesized ruthenium complex. The IR results are shown in Figure A.4 The starting material, K [EDTA], is plotted by the red line, 3 showing two peaks at wavelengths of 1630 and 1597 cm-1. Two samples of K[RuII(EDTA)] synthesized from different batches are plotted by the solid green line and the orange line. On the IR spectra for the synthesized K[RuII(EDTA)], the two peaks at 1630 and 1597 cm-1 on IR spectrum for pure K [EDTA] 3 disappeared and two new peaks at 1724 (free -COOH) and 1610 cm-1 (coordinated –COO-). The IR spectrum of synthesized K[RuII(EDTA)] is consistent with literature reported IR spectra of the same material, confirming the structure of the synthesized material [266-268]. 140
UWA	4) Keep stirring until NaBH completely dissolved (fume hood) 4 Step 3 Fe(H) (P(OEt) ) _ethanol – solution (III) 2 3 4 1) Connect solution (I) flask to Schlenk Line with Ar flowing through and then put it into an ice bath (Schlenk Line) 2) Dropwise add solution (II) into solution (I) – a lot of H is supposed to be produced. (Schlenk 2 Line) 3) Keep stirring for 24 hours (Schlenk Line) Step 4 Fe(H) (P(OEt) ) powder 2 3 4 1) Connect a vacuum pump to solution (III) flask (Schlenk Line) 2) Set up a water bath with T=40 3) Evaporate all the ethanol from solution (III) and then back fill the flask with Ar (Schlenk Line) ℃ 4) Collect the powder (in glovebox) Step 5 Fe(H) (P(OEt) ) _TEG – solution (IV) 2 3 4 1) Calculate Fe(H) (P(OEt) ) yield on the base of Fe 2 3 4 2) Add 3 g Fe(H) (P(OEt) ) into 10 g TEG and keep the solution stirring for 24 hours (in 2 3 4 glovebox) 3) Filtrate any left sedimentation if there would be any and collect the filtrated solution. (in glovebox) 4) Transfer a certain amount of this TEG solution into solubility cell which is ready for N /CH 2 4 solubility tests. (in glovebox) 145
UWA	11 ABSTRACT The thesis develops an original model of asset management applicable to a wide range of work areas and business functions associated with the management of assets in the electricity transmission business. Central to the new model is a way in which those individual areas and functions, although widely used in other existing models and systems, are systematically integrated in a composite dynamic model including business function interactions encountered in transmission asset management. The model also serves to ensure that each of those areas is defined and executed on time and in alignment with all other relevant areas, with a proper and timely influence of each function to the other relevant functions. The model firstly identifies the main areas and functions of transmission business asset management. Secondly, it identifies and defines improvements and requirements for each of these work areas (model components). Thirdly, it defines the required asset management business functions and a proper mechanism for those functions to perform their work to cover all work areas of asset management in the transmission business. The developed model leads to an asset management environment where the individual model's functions and areas will be implemented in a coherent and integrated way. The model sets out the ongoing and timely interactions amongst the model functions, and then defines all required exchange information blocks and their contents for information they need to share among themselves during those bilateral or multilateral interactions.
UWA	iii It is recognised that some aspects of this new model have been known for some time, and have been explored in various ways in some organisations. The main work areas would be those activities that cover asset maintenance and repairs, replacement of assets, asset condition assessment, planning for new assets in network, asset failure reports, and asset reliability studies. Prior to the development of the new model, the thesis reports the results of a comprehensive survey of literature for existing approaches to asset management in general and to transmission asset management in particular. It also gives asset management and maintenance policies and practices in use in many national and international companies. Key deficiencies in the existing approaches have been identified. The work in these areas has been mainly performed in business functions independently of one another or with occasional individual interactions with one or a few other functions. However, full interactions and the timely transfer of information for work areas amongst different business functions have not been a focus in the existing asset management models. The existing models are still based on the functions individuality when they performing their work, and with significant time lags for any transfer of information between them where such an information transfer is being requested by any of them. The transfer is represented by a loose one-way street traffic, ie it might not even happen as it is based on a voluntary effort of other functions. The
UWA	IV significant lag in the case of an eventual access to the information could at best make the information irrelevant, where it has become redundant or even worse superseded. At the worst it could be misleading or even dangerous for the work outcomes in other areas if it is used without the knowledge of its possible obsolescence. In the past these areas and functions have previously not been developed with fully defined and documented requirements and procedures. They have also not been interconnected into an integrated dynamic model where there is full integration and almost an instant interaction of all individual functions that achieves the envisaged aim of this research. The thesis has searched for ways to remove those drawbacks, and new developments for functions and their links, that would lead to process improvements, have been investigated and incorporated in the new model. The thesis formulates a framework for the documentation necessary for the definition of all the required business functions, activities that these functions must perform to cover all work areas, and the process they need to follow in doing so. The thesis also sets out procedures and their sequence to link them in a dynamic integrated way to achieve all the objectives set up in this new model for successful asset management in the transmission business. Finally, the thesis formulates the above-referred documentation and procedures in sufficient details so that the developed asset management model may be fully implemented.
UWA	V STATEMENT OF ORIGINALITY The main original research contributions made in the thesis are as follows: (i) A new asset management model; (ii) The development of a general framework for any new model with general policy documents; (iii) The development of a comprehensive business case analysis; (iv) The development of databases together with data acquisition process for supporting functions; (v) The development of comprehensive documentation procedures. The new model developed in the thesis has the following key features: • Addressing the deficiencies of the existing models; • Including integrated and dynamic process presentation and optimisation; • Taking into account the interactions amongst business functions; • On-going linking of procedures for a continuous risk assessment. The thesis is supported by a series of fourteen publications published in the open literature, presented at conferences and at invited lectures on related subject area of the thesis, detailed in Chapter 18: 3 papers at National Conferences [1,2,14]; 3 papers at International Conferences [3,7,13]; 3 publications at Industry Forums [4,5,12]; 5 lectures and presentations at Technical Society Meetings and University Workshops [6,8,9,10,11].
UWA	1 /. INTRODUCTION The overall performance of an electricity system depends on the reliability of its transmission network, which in turn relies on the performance of its individual assets. The condition of the assets and their operational availability ultimately govern the performance of the relevant transmission network, as these assets are the building blocks of the transmission network itself. With the ageing of transmission network assets and rising expectations for an increase in the rate of utilising these assets and the reliability of their service performance, an organised and well executed management for those assets for the short- and long-term periods has therefore become the first priority for transmission network businesses. In addition, there are increasing political pressures and pressure from the electricity industry (national and international) with the introduction of external competition (through open access policy and general wheeling arrangements in the transmission networks), and an internal desire to achieve better management practices than those of other national and international companies. Transmission networks consist of many different assets (lines, substations, primary and secondary plant). They all have a definitive life expectancy, and some of them have a high capital cost. As their condition deteriorates with age and operation, it is reasonable to expect their failure in service at a certain point in time. When they actually fail, the impact of such a failure could be serious, from a major loss of supply and prolonged restoration
UWA	2 period, endangering of public and employees safety, serious environmental aspects, to significant unplanned maintenance and capital budget blow-outs. Assessment of the asset condition and planning of its replacement just before the failure is not a simple task. It requires the collection of much data from a number of sources through many procedures, often over a considerable period of time. Only then can any useful information be produced through various reporting formats for the necessary asset performance and condition reviews, which would enable meaningful solid decision making. The actual decision to replace an old or suspect asset is further complicated by a number of important influences to the relevant work areas from many other functions of the transmission business. Their inputs have to be taken into account with a particular emphasis on the timing of those influencing factors. The main influencing factors include: • current and future planning and reliability criteria; • current and future operational circumstances; • estimated load and fault level growths; • assessment of the future reliability levels and their impact on the transmission network and overall system; • subsequent possible liability risks; • repercussions of increased maintenance requirements on the maintenance costs;
UWA	3 • asset availability and impact on adjacent circuits; • future and present environment risks; • possible emerging technologies and their impact. Literature survey and research undertaken and presented in Chapter 2 found a few available references relevant to the area of transmission asset management, with most of the researched references based on conventional methods. Those references did not cover all of the aspects of asset problem identification, and subsequent decision making about the asset future. That prompted the need for the survey of other literature covering asset management modelling in general, and also placed more emphasis on the review of models currently in use by various transmission businesses around the world. It resulted in the candidate visiting and analysing a large number of relevant Australian and international electricity companies. The review of findings from those visits and a comparative study summary are presented in more detail in Chapter 3. At present, transmission asset management is most commonly performed in separate, often disjointed, areas of individual companies, where some of the required important functions are analysing or reviewing necessary work on a limited and separate basis. While some of the approaches are fairly sophisticated and detailed, two main aspects of the proper transmission asset management have not been covered.
UWA	4 One is the identification of all transmission business functions required for the asset management in a complete framework with a full definition of their parameters and requirements for their work and input and output information. That includes the databases and procedures necessary to maintain them to provide the defined information required in the asset management process. The other is the definition of links between the main asset management function and other relevant transmission business functions to integrate their defined interactions in a timely manner. The aim of thesis has been to produce a practical and streamlined transmission asset management process based on a new model that will address the above mentioned problems. It is necessary to define all relevant work areas and business functions that need to be included in the model process, and then to implement a number of procedures that will ensure those functions and areas are fully covered irrespective of the organisational structure of the transmission business. Extensive reviews and discussions with fellow engineers and university scholars, both nationally and internationally, during the above research, through other business visits, and attendance of relevant conferences and workshops have revealed no such encompassing model is currently available.
UWA	6 2. CRITICAL REVIEW OF THE PUBLISHED LITERATURE The need for taking care of one's assets becomes apparent to the uninitiated user of any asset only when the item fails. It is then that the unsuspecting user is confronted with two major facts: • the failed item requires repairs to hopefully return it back to service, or replacement; • the failed item also causes the failure of a part of or for the whole process that uses it to come to a halt until the failed item is repaired or replaced. The above situation has raised a number of questions about the issues of: • readiness and appropriateness of the response to failures and repairs (corrective response); • could the failure have been prevented (asset maintenance system by earlier attention to the item, or predicted (asset management system) so that action could have been planned prior to the failure. It is the awareness accumulated over time that there is an ultimate prize for the business in terms of financial, operational and legislative performances and other gains by: • knowing one's assets ongoing condition; • required adequate attention level and timing; • long-term asset maintenance plans, and their timely adjustments; • and long-term plans for a controlled asset renewal process.
UWA	7 The comprehensive review undertaken is not confined to the literature covering transmission electricity type businesses only. The review also covered a range of other available approaches in the field of managing assets in the areas of maintenance and renewal (intervention and replacement) that could be helpful in assessing the needs and options for managing assets in the transmission business environment. The researched literature can be split into five distinctive categories: a) dealing with maintenance and repair works, and their optimisation in a narrow sense of asset maintenance management; b) realisation that there is a need for asset replacement policies as all asset have a definite life expectancy and will fail in service eventually; c) how to achieve an optimal mix of the above requirements; d) information and use of databases and computer systems to collect and report on them; e) discussion about the need for and implementation of suitable systems in various companies, especially in electricity transmission businesses. The presentations in Sections 2.1 to 2.5 show the background, thinking, discussions and proposed solutions from the analysed literature about many aspects of the above areas with their critical review. The obtained and analysed information has been used to indicate where and what major improvements could be made when attempting to build a new complete model to ensure the model answers the questions, challenges and process gaps that have been identified throughout the research.
UWA	8 2.1. Maintenance A concept of maintenance management and the need to be prepared for repairs has been previously used mining operations, always perceived as being at the forefront of maintenance management. The presentation by Dyson[5] is a good starting point showing a number of areas that should be considered for asset maintenance. It is also a good example of a process where individual parts are not fully connected with clear links among them. Developments that took into account variations in the maintenance approach with the costs of corrective maintenance compared to that of applying only preventive and scheduled maintenance are given in paper by Sheu[26]. It presents an attempt to assess the cost impacts between the two approaches and then to decide which one to apply. This theme continues in paper byParikh[22] and with the acknowledgment of the importance of a structured approach to data collection to enable decision making for the area of maintenance itself. There is an awareness that condition monitoring helps with the appropriateness of the maintenance levels to be applied and of their correct timing. This indicates that, with most of the aspects of maintenance well defined, the next step would have to be to somehow integrate them into a framework that will link them and allow further work. An attempt is given in a presentation by Dekker[3] that clearly indicates such a need for integration of planning, setting and combining maintenance activities, with reference to their optimisation.
UWA	9 In further work by Dekker[4], the need for more work highlighting the need for proper data about maintenance activities is necessary to be able to apply such optimisation. Dekker's brief overview of objectives and history of asset maintenance in this paper is a good example of all the issues at the heart of the problems raised, and forms the heart of this thesis. The paper continues to discuss the many problems in maintenance management as compared to other known management areas, and the importance of setting correct asset and data hierarchies to be able to manage the assets properly. It further identifies the need for maintenance optimisation models and for the introduction of computer software applications to enable such optimisation. It also quite rightly highlights that this area will need much future work, as many more areas are likely to be identified and will need to be connected into a complete picture, with further economic pressures and when the need for change in the culture of asset management develops in the industry. Some literature deals with improvements in the maintenance area itself by reviewing different maintenance categories and their place in maintenance management. The discussion by Eby[9] is useful as it points out possible benefits of having correctly defined and used maintenance categories and the right mixture in their application. It also refers to various techniques used for analysing maintenance data to assess the asset condition and optimise its maintenance.
UWA	10 Similar area is detailed in the presentation by Pintelon[23] on improvements in maintenance management decision making by having proper classification and understanding of the maintenance work. It refers to management policy and objectives, a good point as it indicates that, for a successful maintenance outcome, there is the need to know the aimed targets up front. There is also a good suggestion on the need for performance reporting and computerised maintenance management systems support to be able to improve maintenance decision-making. Another approach to maintenance in this paper given by Langan[14] champions the importance of excellence in maintenance process management, as achieved by preparing, implementing, and ensuring a strict and constant use of relevant and easy to access documentation. It also acknowledges that information is the key to success, and that having a good information system and procedures in such a process are critical business issues. He stresses that further benefits for the business could be gained by the implementation and use of new computer maintenance management software packages that can offer quick information turnarounds. In addition to the above aspects, de Haas[3 3] brings into focus the integration of the maintenance and production functions within the company's business plan, and an alignment of its working areas to understand and support those functions. The paper identifies the need for some important elements for achieving a systematic model for maintenance work such as maintenance mission, strategy and policies.
UWA	11 It then concludes that there is the need to have a proper organisational structure, planning and scheduling process and support systems for understanding the process, so that other procedures, eg continuous improvements, can succeed. The summary by Moubray[18] is a good indicator of how to enable transformation of the maintenance management area into the asset management area. It deals with common perceptions in many companies of what constitutes maintenance, and what is expected of the maintenance management area to perform its function. It develops an argument to prove that all of the above is still not enough, by indicating the changes necessary to take the quality and outcome of this whole work to another level, bringing substantial benefits to the business. The paper also warns that the path is not an easy one, as it requires changes and a shift in the culture of thinking and working patterns to be able to overcome those entrenched paradigms. It will take time to do it properly, and each area should be fully covered. The final work arrangements should be set up in such a way that the set-up process makes improvements part of the journey, and not the one-off destination. This theme of efforts to transform a simple maintenance activity into an organised asset maintenance process, with a detailed asset and maintenance strategy documentation and links to corporate objectives, is shown in detail by Wilson[34]. It also indicates a possible way of developing, planning and implementing such an approach to the maintenance process.
UWA	12 2.2. Replacement Issues A partial or full replacement of an asset is a logical step in asset life, and a relevant decision to replace it or discard it will have to be reached at some point in its life. This step must be included in any complete model, together with the procedures to obtain the necessary information about the asset, its purpose and surroundings, and how to deal with the new step within the many business functions of the organisation. Jardine[ll] supports the issue of a complete approach, and gives aspects of replacement approach requirements. The paper documents the need for a defined framework to be able to reach such decisions with confidence. It also points out the requirements for information and proper tools, including decision-making software, required to optimise the process for the correct decision. A short review of the maintenance process and where and how it should start considering plant replacement as the part of the process is given by Lambert[16] as an aim in improving the asset performance (asset being the whole of plant operation). It is an analysis of the effects of the individual components and information about their performance, obtained from the proper registering and monitoring of performance of the individual components, on the operation of the whole system. That should eventually enable the asset operator and asset maintainer to make the right decisions about either completing further repairs on the asset or initiate its replacement.
UWA	13 In his editorial paper on models for maintenance management of assets, Van der Duyn Schouten[29] has elaborated on a number of papers dealing with the various aspects of that topic. But most importantly the paper makes a significant reference for the need to have better-suited asset replacement policies than those available, as most companies currently adopt mainly replacement policies based on asset age and general asset distribution. 2.3. Optimal Policy Mix It has become obvious to a number of authors that, having developed a replacement policy on the top of maintenance works, there needs to be a mix of both repairs and replacement, as in presentation byBorg[2], which shows how to apply marginal cost analysis. The presented model relies on cost analysis, but confirms that more is required in the form of planning availability of recommended replacements. There are also other presented factors that should be reviewed and addressed within an eventual complete model. A similar approach is taken by Dekker[6], in explaining that there is the need to adopt a better way of looking into the maintenance process and that by introduction of maintenance optimisation. It also highlights important requirements to have data specified and collected for a meaningful operation for any optimisation to work. It then supports clear requirements for proper and relevant software packages to enable such an optimisation between various aspects of maintenance works, which is supported in other papers discussed in Section 2.4.
UWA	14 Another good presentation about the need to achieve a proper mix of maintenance expenditure and capital funds for asset renewal projects is given by Kaiser[13] through the positioning of such work within the company. The presentation starts with useful explanation of commonly used terms in the asset management area, and continues to define how the problem of planning asset replacement has originated. It also presents comments on the size of the replacement problem, particularly if not dealt with for a long period of time. There is helpful insight into the approach of striking a balance between the required capital funds for asset renewal and the maintenance funds for planned and deferred maintenance work through a good asset management programme. The paper rightly draws the attention to the fact that long-term capital asset renewal plans are absolutely necessary to make such a programme successful. There also needs to be a good monitoring system in place to ensure the programme and all its activities achieve a target set-up when introducing such a programme. In the presentation about the need to move away from maintenance as an isolated process of fixing things as they happen, Newton[20] very effectively shows that many other areas should be involved in an expanded process. The presentation then explains the requirements for a good mix of all those areas to improve the whole process. In that way, the expanded maintenance process will better support the company's assets throughout their life, and truly achieve benefits to the business as a whole.
UWA	15 Thinking in a similar fashion is a presentation byTownsend[27], where the notion of incorporating the narrow asset maintenance management to a wider arena of asset management is correctly expanded. It supports the need to have a proper relationship established between the two areas, which will improve an overall contribution to the transmission business bottom line. It also briefly mentions the process of decommissioning and disposal of the asset, but without any more information about that process. There is an important and valuable observation that for any asset management system to be effective, properly defined responsibilities need to be placed on organisational areas whatever their outlook. 2.4. Information and Use of Databases and Computer Systems Even the earliest works acknowledge the difficulties for organisations when they attempt to implement an asset management strategy without having the right information to start with and then to waste time working on it afterwards. It is becoming obvious that for a good management of assets there is the need for good data and efficient systems to access necessary data quickly so that it always provides the right information on time for the proper decision making. To achieve those goals the basic maintenance management process must first be under control, as presented by Newby[21] in the work about integration of maintenance work control. Implementation of collection and assembly of all relevant data about the maintenance activities for its control, through a proper maintenance management software, serves initially only to enable proper planning and programming of maintenance work.
UWA	16 But the wealth of such information, once achieved, will form the basis for a more advanced asset management process to improve decision making between maintenance and other problem resolution options. Similarly, a project to have asset maintenance management under better control by designing and implementing a combined planning and control system has been explained by Ulusoy[28] through defining the required structure of the database, classification of assets and their maintenance tasks, and then running reports and analysing asset performance. Another example of the value of the development and implementation of an integrated technical information system to support maintenance work is presented by Lundberg[15] where he shows the experienced preparation and use of such a system. The previously used system had a number of independent procedures for planning, scheduling and for management of contractors, with very difficult and time limited data transfers between them. The new system enables efficient operation and maintenance recording so to achieve an improvement to the whole process. The paper concludes that developing optional graphic and geographical functions could make further improvements. Such individual systems (maintenance activities, technical support) later lead to a more complex approach to data management, especially in the area of transmission business assets, as shown in an elaboration by Drye[7]. It guides well through the main points to justify the need for such data management in the relevant asset management process.
UWA	17 It explains the asset data requirements must be defined as well as the performance and failures. It is therefore very important to determine what a failure is for a particular asset type and a coding to properly register it when it happens. It then highlights the need for proper information systems for the asset management business, and provides some leads for what those systems should cover. They include the registration of all assets, definition of the assets maintenance requirements and then setting them into a maintenance management application, and ensuring that the defined and required work is planned and executed through a suitable work management application. There is also a good reference to the importance of proper data flow and its sequences, ie acquisition, entering and processing data. An integrated and structured approach as an attempt to improve the maintenance procedure through setting up an information system to enable data recording, later reviews, and further analysis of asset performance and condition is shown in paper by Vanneste[30]. It presents the experience of implementation of such an information system in a typical manufacturing line. It supports the notion that such arrangements must be in place to have any real chance of understanding and controlling the above maintenance procedure. A more complex and sophisticated system for the collection and recording of the data and exchange of information is presented by McRae[19]as developed and implemented in one company. It shows how such a system is an absolute necessity for a business aiming to be truly successful in the management of its assets.
UWA	18 An important aspect in the benefits of collected data and output information through the use of business computer applications and databases to improve the overall asset management and maintenance standards is raised by Smith[25] in the presentation on the benefits of benchmarking. This is the process of taking relevant data from various similar companies, comparing them in agreed ways, and providing feedback on an industry average, existing best practices, and one's own standing in relation to those two yardsticks. It is essential that a proper baseline of areas intended for comparison is ensured so that the benchmarked companies can be compared accurately. That will sometimes call for significant time and effort in any business attempting to take part in the benchmarking to work out the necessary information and to present it in the right format. The benchmarking can be done internally and externally, and a deep and honest review of the results can reveal many opportunities for improvements in many areas in the business ways. But it is especially important to be very careful when examining results from the external benchmark studies. Many specific circumstances (whether one's own or those of other companies) may render good ideas and practices unsuitable, impractical or just too expensive to use. But it is clear that such tools should be incorporated in any complete model to ensure good auditing of the process, its functions and the results it produces, then making comparison with other companies to find the best solutions. An interesting contribution for the need to have as much information as possible about the asset maintenance process and asset itself to enable further inroads in the areas of maintenance optimisation, prediction of asset
UWA	19 end of life, and the correct mixture of maintenance and renewal asset activities is given by Noortwijk[31]. It shows how a complex expert judgement technique could eventually be introduced when enough data is available. 2.5. Need For a Whole System It is evident from the literature that there is a growing need for an integrated asset management system suitable for any complex business, and of course, specially the one suitable for an electricity transmission business. Paper by Moubray[17] points out some distinctive requirements for a complete solution. A maintenance mission statement should be a logical starting point that will clearly identify the main players (asset owner, operator and maintainer, and society as a whole represented through various government and other bodies) and their roles and responsibilities. Then defines different maintenance work categories and rules for the most cost-effective application that will satisfy all stakeholders. The next step would be the development and implementation of one's own maintenance strategy. The strategy should recognise several main factors; need for a maintenance policy for each asset, proper structure to cover all required work, and define, acquire, deploy and operate the systems needed to execute the strategy. The paper makes a brief reference to monitoring of asset performance that in turn requires a suitable computer maintenance management system, which should be selected with a due diligence and care only when the previously described documentation, systems and culture are in place. That covers some aspects of the issues already reviewed in Section 2.4.
UWA	20 It highlights the requirement for an audit of the asset management process and its functions and procedures, which has not been properly included and acted upon in asset management activities in the past. Any new model offering a complete approach should ensure that regular audits are included. It should also prove that not only the right things are being done, but also demonstrate in writing the reasons for doing them. It also shortly refers to the need for accounting and financial functions embedded in the asset management process and to work with them hand in hand for asset maintenance, repairs and replacement strategies. It is definitively something that any new complete model must achieve. A similar need for a new approach to asset management is given by Eyre- Jackson[8], with discussions on the merits of various new ideas about the planning and introduction of a full life-cycle asset management. The paper defines the asset itself and its position and role in the asset life-cycle. It correctly identifies the start and finish of asset life, and the possible steps in the asset life. It then explores various points regarding a strategy for adopting a modern business system to be able to achieve the benefits of the full life-cycle approach. It hints at the possible benefits that full utilisation of such a complete system might have on the bottom line of public utilities with long life assets and how it could assist them with their long-term plans to smooth their future expenditures. That is exactly what any new model should strive to achieve. Paper by Hancock[10] correctly identifies that the definition and the configuration of asset management programme is the main prerogative in achieving a proper control of operation and maintenance procedures and
UWA	21 costs. It is aiming for such a programme through the definition and implementation of a comprehensive documented process. Once in operation, it should provide significant dividends to the company. It is also important to consider that the final step of any good programme is that there is no final step. Instead, theprogramme itself, once working, should also receive the ongoing attention in some shape or form to cater for its own continual support and improvement. Integration of various steps and functions as a useful step forward to enable better maintenance of assets is shown by Powys[24] through an extensive presentation on improving the planned maintenance of assets within the public sector. The main focus is to assemble a complete picture with the input of community demands and government goals combined into the corporate plan to create an asset strategy to guide the asset manager. There is a good understanding and presentation of necessary major steps towards the implementation of maintenance from the above-agreed strategy, including the need to monitor and review performance based on developed performance indicators. There is also brief reference to renewals (adaptations) throughout the asset life and its final disposal somewhere down the line as categories in the asset life cycle, as a positive sign of understanding the importance of those categories. As no more information is provided, it is probably only an indicator of what should be done, so that in the future the renewals would be accounted for in the process. An excellent example of a successful system is given in paper byJones[12] in explaining the flow of process as adopted in an electricity business.
UWA	22 It begins with a decision to introduce an asset management culture, then produces an asset management mission and strategy, and then aims to implement an integrated approach to asset management process of the own making. There is a distinctive set-up of asset life-cycle phase and a strategy in place for each of the identified phases. The phases include many important aspects that are considered to be essential parts of a good asset management process, although links and requirements to other parts of the organisation are not given. There are brief references to the need to look into modelling of the impact of asset performance and decisions within asset management of the whole company, and to have cross-organisational reviews of results of asset maintenance and performance. Both of those references are valid and helpful as they point out the necessities of a complete model in order to be judged successful. Similar support from the reviewed literature for an integrated asset management system suitable for electricity transmission businesses is well explained in a presentation by Allison[l]. It points out some distinctive requirements of a complete solution, starting from a basic necessity to ensure monitoring of asset performance in service. That would obviously require data to analyse, which in turn requires a proper network for incident recording. The presentation also highlights the need for a suitable computer database and maintenance management computer system, which covers those needs as shown in other reviews in Section 2.4. The presentation then follows with a need to develop and implement a maintenance policy for the asset and to attempt to assess asset condition, to be able to make predictions about its life expectancy.
UWA	24 3. COMPARISON TO OTHER ORGANISATIONS There are many electricity supply companies currently operating in Australia and overseas that include the transmission business component and a selection of them have been visited in the course of this research. The visits have been used to review the way each operates, to assess their asset management process and its main work and business functions. Subsequently, a brief summary of findings has been prepared about the knowledge and information gained in each visit. The summary has also been used as a guide to identify improvements to the current process, which will improve their asset management and point out issues that any new model needs to address. The visited utilities are listed below: - National Grid Company (NGC), Coventry, UK; - Yorkshire Electricity, Leeds, UK; - Midland Electricity, Birmingham, UK; - London Electricity, London, UK; - Boston Edison, Boston, MA, US; - Duke Energy Company, Charlotte, NC, US; - Tennessee Valley Authority, Chattanooga, TN, US; - TransGrid, Sydney, NSW; - Powernet, Melbourne, VIC; - Hydro-Quebec, Montreal, Canada; - HEP, Zagreb, Croatia. A comparative summary of all findings from the individual visit briefs has been prepared to show:
UWA	25 - share commonalities and what they are; - drawbacks in the way they operate; - missing components and the links in the process; - what is missing in the sense of integration of the interlinking for feedback information, and in the proper timing for their feedback relevance; - requirements of a new model in order to address all of the above to lead to improvements, and the ability to properly manage the relevant areas as identified and explained in the comparative summary in Section 3.2. 3.1. Brief of Individual Companies The summary of findings from visits to the listed companies is presented in Sections 3.1.1 to 3.1.11. 3.1.1. National Grid Company One group looks after substation, switchgear and protection areas with the responsibility for maintenance management, ie to prepare an annual maintenance work plan and the corresponding required outage plan, and to prepare and submit proposed annual maintenance budget. Service providers have implemented a work management system for use in maintenance planning but many modules are not in use yet. There are no
UWA	26 links to the equipment register or to failures database, which are run independently on a separate indication system. The important asset management work (population and age statistics, failure investigations and failure statistics, asset condition investigations, and assessment of remaining life estimates) is done by other groups, ie substation and line design sections, also charged with producing maintenance policies. Refurbishment, modification and replacement recommendations, together with economical and technical aspects of business case preparation, with its financial evaluation for justifying asset replacement decisions (NPV timing and age profile of plant type) are again done by another group. There has been an attempt to provide an assessment of the importance for all active transmission circuits in a system by assigning a factor 1-5 to identify how critical they are in the system operations. No significant contingency planning to handle emergency power restoration and plant replacement arising from unexpected plant failures, apparently due to a lot of spare capacity. The purchasing group centrally registers all plant on order, and provides services for the plant data input in the equipment register. 3.1.2. Yorkshire Electricity Asset management group plans maintenance and has a service level agreement with field operations, supported by technical people in the
UWA	27 technical operations group, while the IT group produces reports to monitor the work and finances. Asset management also does budgeting, cost control, extra funding for additional corrective work, emergency work funding, produces maintenance criteria, analyses feedback, and updates manuals. The annual plan is not prepared and submitted annually, as the work arrangements are left to the technical operations for major refurbishment projects and to the field operations for the regular maintenance work throughout the year. There is a work management computer system for maintenance work linked to an asset register database, but there is no asset management software. Asset management of long-term planning is rudimentary as population and age statistics are not used very much. Major failure investigations, with subsequent asset condition investigations, are used to determine replacement candidates on an individual case-by-case basis. Assessment of remaining life estimates are taken into account to determine possible blow-outs in future replacement requirements, but the whole of the life cost factor is low in priority when deciding on refurbishments, modifications and replacements of plant. Business case recommendations use predominantly safety, customer implications, legal and regulatory issues, environmental performance, and company perception of impacts (for customers and the regulator).
UWA	28 Contingency plans for emergency conditions do not exist as there is apparently enough capacity everywhere, and the emergency replacement plant is sourced from the pool of the incoming plant ordered for projects or asset replacement programme. Asset condition monitoring is considered of no practical value to the business. Asset data register updating is a basic one through paper sheets filled in situ by construction staff, and sent to the information technology group to be entered. Registration of the plant on order together with data input in the equipment register does not exist in that early phase. 3.1.3. Midland Electricity, Birmingham Maintenance is planned annually by the depot maintenance groups, which arrange for the budget and perform the work. The work progress is monitored through some reports to the service provider and asset manager. The maintenance criteria and update of manuals are done by the asset manager and entered into the plant maintenance recording database, which other groups then refers to. A work management system is partially used, to provide mainly financial reporting. There are also no line asset database and no asset management software. Asset management nominally owns the asset data register, but updating is completed manually based on forms filled in by construction teams on site.
UWA	29 Another group analyses population and age statistics; performs failure investigations and asset condition investigations; and estimates asset remaining life. The business case preparation includes some economical and technical aspects, but is mainly based on financial evaluation models to justify asset replacement decisions (NPV of timing and age profile of plant type). There has been some reference to the future age profiles and questions on the ability to manage all these in the future, as the total capital expenditure commitments are based on overall plant profiles and asset values with the assessment of remaining life. All prepared and approved proposals for refurbishment, modification and replacement of an asset are then included in the company's normal annual plan. Contingency plans for emergency conditions of major assets are not considered necessary and are not prepared. There is no central registration of the plant on order, and subsequent input of their data in the equipment register. 3.1.4. London Electricity Asset management group does the long-term maintenance plans but the service providers prepare the annual maintenance plans, required budgets and system access applications for the maintenance work. They also do maintenance criteria, with feedback and updates of manuals.
UWA	30 A separate section monitors their work and reports to the service provider and the asset manager with various reports. The maintenance service providers perform budgeting, scheduling, work and finance monitoring, cost control and arrange for extra funding for additional corrective work and emergency work. All their requests for major asset repairs or requests for modifications need to be referred to the asset management department for the review and approval of those requests. All requests for new plant are also referred to the asset management, who in consultation with plant purchasers decide which new plant to allocate, budget for and purchase for a particular case. The replacement plant is sourced from the project pool, and no strategic spares are held. Purchasing department arranges with projects to issue drawings and updates the equipment data register. Financial management system where maintenance costs are registered is separate from the work management software. Population and age statistics and failure statistics are performed based on estimates of an overall population to calculate expected funds that would be necessary for the replacement of assets. Individual asset failure investigations are used of to assess asset condition and its remaining life to determine the life expectancy of each plan type. Economical and technical aspects, including financial evaluation models for justifying asset replacement decisions rely heavily on the total plant
UWA	31 profiles, and general capital expenditure commitments are based on the overall asset reliability assessments (no detailed asset databases). Contingency plans for emergency conditions are not prepared with respect to the relevant contingency scenarios, with no instructions on the response options, responsibility, ownership and updating. The concept relies heavily on the expectation that the network has sufficient redundancies in itself to cover outages, where operational staff will pursue repair requirements through various groups when the contingency occurs. 3.1.5. Boston Edison One group does life cycle planning annually and on a long term. Various other groups, mainly on their own, do the work through service level agreements. Most reports are produced for all groups by one performance- monitoring group that also owns the asset data register. The service provider crews though maintain the register. All budgeting, scheduling, work and finance monitoring, cost control, extra funding for additional corrective work, emergency work funding, maintenance criteria, feed-back, and update of manuals are done by the maintenance service providers. A separate contracts group looks after all internal and external service providers. Their work management system is basic with no asset management software.
UWA	32 There is a separate group for investment planning that prepares standard costing for all asset projects, and provides feedback for all maintenance and capital works progress against the initial approved plan. Another group performs population and age statistics, failure investigations and failure statistics, asset condition investigations and an assessment of the remaining life of the asset. The same group prepares business case recommendations for refurbishments, modifications and replacements of plant, which includes some economical and technical aspects in the business case preparation, but with little financial evaluation. No standards for business case preparation models are available when preparing and justifying asset replacement decisions. There is no registration of the plant on order and subsequent input of their data in the asset register. 3.1.6. Duke Energy Company Corporate accounting section advises the funds available in the ensuing periods for the maintenance and capital expenditures to be transferred into the plans that will be prepared in such a way to match these funds. Asset management plans the work that is handed over to the maintenance service groups to run the work schedule. The service groups decide to do work or give it to outside service providers. The work is presented on paper schedules with 1-2 month intervals, with the paper work sent back to complete the work record in their internal
UWA	33 work management system to enable reporting. There is no accounting link, and the costs are manually entered based on provided sheets. The scheduling, planning and execution by the service providers are monitored through those reports. The work progress and finance monitoring, cost control, funding for additional corrective work and emergency work funding are done by the asset management, but in a complicated way with unclear accountabilities and information flow. The same group prepares maintenance criteria, receives feedback and updates the manuals, but the process directions and requirements are not specified in any detailed documentation. They include some economical and technical aspects in the prepared business cases to support financial evaluation for justifying asset replacement decisions. Contingency plans for emergency conditions are not prepared, but the annual plan may contain some recommendations for critical plant. There is a basic asset register based on sheets sent from site. There is no central registration of the plant on order and subsequent input of their data in the asset register, which is acknowledged and seen as a problem for a quick identification of available spares in a fault situation. 3.1.7. Tennessee Valley Authority Transmission support group plans maintenance annually and transfers data on regular basis to service groups, which are fairly independent in their
UWA	34 work and the asset manager has poor control and overview of the progress of their work. They also prepare maintenance criteria, monitor feedback and update the manuals as seen fit. The maintenance work progress is monitored by each group and by the transmission support group and discussed in monthly meetings between the service providers and the asset manager. The maintenance work is done with no service level agreements. There is a basic work management system as it does not include costs and has no links to the asset management software. There are no specific contingency plans for emergency conditions. A separate asset analysis group does population and age statistics, failure investigations and failure statistics, asset condition investigations, and assessment of remaining life. The results are used in another group to prepare a business case and recommendations for a refurbishment, modification or replacement of an asset. These recommendations contain some basic technical (failures, difficulties in operation, critical circuit assessment) and economical aspects for the relevant asset, but they are not based on any standard model as there is no detailed documentation on how to prepare a standard business case. The registering of the assets is poor, and completed mainly by procurement and construction staff in the work management database (no separate
UWA	35 equipment database) based on order data, with asset serial numbers and location added later based on eventually-supplied field reporting sheets. 3.1.8. TransGrid Asset management (called asset performance) covers the responsibility for asset strategies, asset performance and feedback on achieving targets, technical support and plant tendering, while other areas look after asset planning, design and maintenance. Asset maintenance management is done through regional areas, which are responsible for: - asset maintenance planning (annual maintenance plans and budgets, and monitoring work progress); - asset maintenance (short-term work scheduling, work backlog control, workforce resource management to complete the submitted required work programme and basic reporting); - asset maintenance support (short-term work analysis and confirmation, technical support, fault response coordination and subsequent individual fault investigation and coordination, review and recommended action to correct one-off plant fault issues raised during the year). Project management and engineering design are two separate areas for the capital works programme but local area managers are ultimately responsible for the projects in their areas. A separate group is responsible for all asset performance reporting and monitoring of reported trends against the assigned targets to maintain the impartiality in the overall process.
UWA	36 3.1.9. Powernet One area of asset management (called assets) covers basically responsibility for asset strategies, asset performance, feedback on targets, benchmarking, asset replacement investment planning and business cases preparation, technical support and plant tendering, maintenance planning, budgeting and control, internal and external service providers management, system incidents and investigation. The main components are primary plant, secondary plant, performance, maintenance, investment planning, and benchmarking. Internal service providers perform 50% of asset maintenance, while the other 50% is done by an external company through a strategic alliance agreement. Engineering design has been moved to a separate entity outside the network business, while the project management is in another separate area, but within the network business, and charged with liaison to the engineering design group. System planning also resides outside the transmission network business in a separate company deliberately set-up by the government. The same approach has been taken when it comes to organising the system control, ie by use of a separate company, in an attempt to ensure an independent control of the way the system and assets are operated. Regulatory, customer care and commercial marketing groups are in the process of merging into one area, as well as the finance, human resources and administration support group.
UWA	37 Capital expenditure for asset replacement is expected to rise significantly in the next 5-10 years because there are many major substations that are 50 years old. Their standard approach in future will be to deal with the whole of substations circuits instead of only with the individual plant, as it eventually increases total costs and reduces reliability with the combination of old and new plant in the same circuit. There are problems with preparation of asset replacement business cases as there is no formal framework in place. The exchange of information and data with network planning and system operations is difficult, especially feedback from asset management about the inclusion of asset condition and replacement plans into the network development plans. It is acknowledged that there is a need to expand reviewed options for plant or substation retirements with different voltages and network designs, and to seek an input from engineering design, which is also proving difficult in the current organisational structure. 3.1.10. Hydro-Quebec Hydro-Quebec is a company that covers the transmission and generation sides of the business, however this report only covers the transmission part of it. The main characteristic of their transmission business is that there are four main regional operating areas, which own their respective assets and are accountable for their performance.
UWA	38 Therefore, they make the final decision on which maintenance and capital works they will execute in each financial year based on the recommendations they receive from their asset management and planning functions. Those functions operate as corporate departments and have supporting and consulting roles in the whole business process. The following work is performed by the areas themselves: maintenance planning, annual budgeting and control of expenditure, management of internal and external service providers, and project management of the projects in their area. The maintenance work is done through a combination of internal and external service providers. One area, ie the asset management department (called asset support), covers the responsibilities of network and asset strategies, maintenance policies, network and asset performance analysis, benchmarking, asset replacement business cases preparations, technical support, and plant tendering for the business. In addition, they support the areas in system incident investigations. Engineering design has also been allocated to this asset support department to provide engineering and design work for the areas. The system planning is a separate part of the business, as well as the system control, regulatory and customer care, and commercial marketing, finance, HR and administration groups. Major issues that have been identified in their work are described in the following: • No standard process and format in place for preparation of asset replacement business cases; • Maintenance plan execution and practices differ from area to area;
UWA	39 • Basic and not very well documented asset registers and data collection, and input not properly controlled; • Input of system and asset problems very much dependent on the areas, and there is no system in place to ensure data quality; • Different format of performance monitoring in areas makes it difficult for the asset support to compare results and analyse the whole of the network; • Exchange of information and programmes with network planning is difficult, especially with feedback from asset management on inclusion of the asset condition and its replacement plans into the development plans; • There is no clear responsibility and accountability for the long-term view on coordination of development of the whole network and substation designs in the future. 3.1.11. HEP The HEP, an electricity company, is also a fully integrated electricity business, ie it still covers the distribution, transmission and generation sides of the business, and is owned by the government as the only shareholder. This report only covers the transmission part of it. The main characteristic of their transmission business is that there are six main regional operating areas, which own their respective assets and are accountable for their performance. The reorganisation of their current structure includes discussion, in a much similar way to other utilities being operated as an integrated electricity business (involving generation, transmission and distribution) about the following main topics:
UWA	40 • various proposals are being discussed on how to split generation, transmission and distribution; • future and roles of the system control centre and a market pool operator; • how to split transmission and distribution parts of the business (at a zone substation level, transformer LV breaker or zone substation fence). The main asset management issues active at the moment are the following: • lack of funds for network expansion and asset replacements due to catch up expenditure to restore the war damaged plant; • there are no formal asset management process and procedure, and it depends too much on the individuals and their ad hoc links and relationships; • too many meetings at technical level involve higher management levels, preventing spending time on the long-term plans and visions; • a lot of investigations are late as there is an acute shortage of experienced engineers due to difficulties of such business to attract new staff; • problems in coordinating budgets and plans for 6 different areas, and ensuring that the same maintenance practices are adhered to; • how to adjust network development plans with the assessment of asset conditions and vice versa. 3.2. Comparative Study Summary This comparative study has been prepared to show a summary of common issues and differences in the management of transmission assets after a review of a number of similar national and international electricity
UWA	41 companies. The study identifies problems and deficiencies that any new model must resolve. A summary of the main points from the reviewed companies pertinent to the development of the proposed asset management model is given in the following paragraphs: The areas of asset management and asset maintenance have now been clearly considered as an important part of the transmission business in all companies. While many have not compiled a complete model or completely understood the process and procedures required to fully integrating all asset management work, there is a general acknowledgment of a need for a complete model. Therefore, they are all aiming to put a structure in place to cover all aspects of asset management functions and are devoting or planning to put significant resources into that work. In general, maintenance service providers do more or less day-to-day scheduling, resource management, some degree of use of work management or maintenance management computer systems, monitoring and reporting status of work and costs. An in-house service provider completed this directly through the internal work management system, and some do that also with the out sourced support. Some asset management groups meet their service providers more often tha others to discuss work progress and problems, with such practice more prevalent in companies that do not use some forms of computer management systems. System studies and planning for network enhancement are done by separate groups, generally not considered an asset management issue. Most companies do not recognise a formal requirement for a need to have asset management
UWA	42 plans and network development plans exchanged and cross-referenced on a regular basis. Most companies also use the network development group to prepare asset replacement business cases for non-performing assets with information to be provided by various other groups, and making this area somewhat convoluted and unclear. There is a vast array of organisational structures applied to cover asset procurement, data registering and ongoing data management for asset location and condition. Some companies have completely neglected that area, which makes it almost impossible to perform a proper asset management, particularly with regard to the long-term planning of their assets renewal. Therefore, they need to resort to general population models and generic asset life expectancy assumptions. These lead to inaccurate predictions about the size and quantity of the coming asset problems, and represent unknown risks to the network operation and viability of business in the future. A number of electricity companies are still gearing towards detailed computer based maintenance management systems, including common line and substation equipment databases, aiming to register their total asset database and to record maintenance costs against each element of their network. Asset replacement strategies in the US are mainly based on individual asset performance, safety and security of critical circuits, and less on age, maintenance costs or replacement age profiles. On the other hand, the UK utilities are spending a lot more of capital money (about 2-3% of their network asset replacement value) on asset replacement projects annually. The main reasons quoted are to avoid high
UWA	43 operational risks and subsequent possible large fines by rigid regulatory bodies their governments have imposed on them. Some companies have attempted to register network critical locations in various formats, issued and updated usually by the system operations function. The register mainly defines the importance of circuits in the network on a scale of 1 to 5 at the various circuit levels. That could prove helpful for their network planning and asset management studies. Some switchgear and transformer maintenance policies are set up in such a way that they recognise a difference between the new equipment and the equipment with 20 years or more in service. Also, higher levels of maintenance are not automatic in some companies, with attempts to base them on the number of operations and various test results obtained during the maintenance (timing tests, contacts resistance measurements, gas content and electrical properties of oil). Generally no serious contingency planning exist as apparently everything in the network is covered double or over, and has been caused by the capital overspending on assets to have a high network security, and to ensure no load loss occurs under any normally expected system fault conditions. That is generally due to the fact that there is little knowledge about their assets (poor registering of assets and activities) and their assets current and long-term condition.
UWA	44 4. CONTRIBUTION AND ADVANTAGES OF THE RECOMMENDED INTEGRATED MODEL The thesis has developed and documented a new asset management model and its process with a number of business functions and their procedures that are appropriate for a transmission business to implement and rely on to efficiently address the problems and deficiencies identified in Chapters 2 and 3. The integrated model covers and defines roles for all business functions necessary for a successful performance of the asset management process in a transmission business, with the required integration of those functions through necessary cross-links and the required timely information flow and exchange for all of the functions. The basic outline of the developed integrated model is presented in Chapter 5. The framework in which the new model is developed is a general one. It is independent of specific organisational structure of any transmission company. This generality is achieved by expressing the framework in terms of required business functions and their roles that are to be fully accounted for in any implemented transmission organisational structure. The model outline, process, relevant procedures and supportive documentation will be developed and described in more details in Chapters 6-15.
UWA	45 The thesis also contains a presentation and discussion of a developed, approved and completed business case for the replacement of a non- performing asset in Chapter 16. The research outcome will enable transmission business companies to implement, use and continually improve the developed integrated asset management model and its process with the defined documentation for the business functions, necessary databases, procedures, production and use of various reports, maintenance working plans and asset renewal programmes. The documentation describes strategy and policy intentions, defined process and procedures to implement them, and required initial and output documents to support the process. The databases establish ways of recording details about assets and their characteristics, position in system, various requirements, actual actions, faults, and future plans. The developed process provides details of all required initial documentation, necessary databases and data recording and reporting, procedures to perform the necessary work in a timely and correct fashion, and specifies working functions to perform those procedures or to provide prescribed inputs for other functions in the set time frames. It also specifies all required output documentation that provide the information necessary to make correct, timely and effective decisions by all interlinked work functions in the asset management process.
UWA	46 The developed model provides the transmission company with a framework to enable proper and timely management of its transmission assets in various business areas. The business areas include setting proper asset maintenance policies and regimes, execution of the prescribed policies through long-term asset maintenance plans, asset operational and financial performance monitoring, and an assessment of their operational and long-term suitability. The model ensures that future long-term asset management plans are prepared for the asset renewal based on all aspects of the asset cost, performance, age distribution, regulatory legislation, environmental requirements and asset critical position in the system. The model also includes a mutual and timely updating of rele/ant network development plans, asset renewal plans and asset maintenance plans. The model process presents the transmission companies with a tool for proper management of the whole asset renewal and maintenance over a period of time in a planned and controlled manner. The process enables the company to continually assess its future work and financial liabilities, and viability of the business, by knowing and reviewing the risks for adopting or not the recommended and planned actions to be followed in the future. That will assist in understanding when and what action to take to limit the potential risks to the system and to the financial health of the company, and to realise any possible savings in long-term maintenance costs by arranging suitable plant renewals.
UWA	48 5. ASSET MANAGEMENT MODEL 5.1. Recommendations for Any New Model The results of the critical review of the published literature and the summary of the asset management practices of the companies visited have been used to indicate the possible improvements or new areas of asset management process, functions and procedures that should be covered by any new model that aims to rectify the identified deficiencies and gaps in the current approaches to the asset management. The results have also been used to define how the identified functions should be interconnected and aligned into an integrated model to provide a timely and complete feedback amongst themselves. That model should bring all the necessary information and options for opportunities and on time to the right people within the company for their consideration and proper decision making. 5.2. Objective of This Work The pressures and constraints that are currently being imposed on all transmission business companies around the world as detailed in Chapters 1 and 3 have placed a clear emphasis on what their ultimate goals must be. The companies are expected to continue delivering improved financial returns from their transmission electricity assets to all their stakeholders (that can include shareholders, government, public and employees in various countries) while at the same time maintaining or increasing the reliability of their assets in operation.
UWA	49 This represents a real challenge to the transmission businesses as they are forced to face challenges of a different kind from those in the past in a situation with ever ageing assets. That is compounded by an environment of a reduction in a possible access time to the network for the same assets for maintenance and renewal works, as requirements for network utilisation and construction works, due to expansion of the network, increase. The objective of the research and this thesis is to develop an answer to that challenge so that the transmission businesses can deal with the above mentioned situations in the best possible way. While many others have not compiled a complete model or completely understood the process and procedures required to fully integrate all asset management work, there is a general acknowledgment that any final complete model and its process will have to integrate all the main areas of work and define necessary asset management business functions. The new asset management model needs to achieve an environment where the functions in place ensure that: • asset maintenance policies and plans are developed and implemented; • all assets in service in the transmission network receive proper care according to those plans; • the assets performance and their overall condition are continuously monitored and assessed while in service; • assets are identified and highlighted where there are problems;
UWA	50 • the reasons for the problems are identified and optimal long-term solutions devised to address those problems for the benefit of the network, company and stakeholders; • maintenance policies and plans are continuously reviewed and improved; • inputs from various defined sources are continuously received and reviewed to respond properly and on time to achieve the best possible short-term and long-term outcomes for management of assets; • all asset related activities are integrated so that their links and procedures achieve a timely and correct interchange of all defined information amongst the relevant functions in the asset management process. It is the intention to show that this can be achieved through the implementation and continuous use of a comprehensive asset management model as developed, defined and proposed in this thesis. 5.3. Development of the New Model The new model has been developed through a number of stages as outlined in the following: a) identification of the mechanism of transmission asset management process in the electricity transmission business; b) identification, definition and requirements of additions or improvement of the main work functions of the identified asset management process; c) identification of the transmission business functions, their required links, and type of the necessary relations between them to cover the specified
UWA	51 work functions of the asset management process. That should not only include information they should provide to one another when required, but also requirements for the interactions to occur within the specified time and relations that have been developed in the asset management process; d) using the outcomes of the above three steps, finalise an integrated asset management model that covers all required aspects of the identified asset management work functions and transmission business functions involved in the asset management process and linking of their required activities for all the assets used in the transmission network (lines, cables, primary and secondary equipment). This linking amongst business functions will enable a continuous and complete exchange of information in a defined set of feedbacks at the prescribed times, achieving a desired dynamic framework. 5.3.1. Identification of Asset Management Process The first step was to identify the mechanism of an asset management process in the transmission business and its functions involved if a successful management of the assets in the active service in the transmission network was to be achieved. This process was wide and covered a large number of the transmission business functions that in some way influence how those assets in service are looked after and how their current and future operational, maintenance and renewal needs are being or will be met.
UWA	54 The asset acquisition may be initiated through a number of different activities resulting in the requirements of new assets in the transmission network: a) need due to new customers, b) growth of the network causing loading to increase above the current asset rating; c) increase in generation and network connections causing fault levels to rise above the current asset rating; d) change in the planning criteria for the parts of the network that the current assets cannot match; e) change in the operational requirements for the parts of the network that the current assets cannot match; f) new requirements for the assets in service brought in by various government or statutory legislation that the current assets cannot satisfy (now or in the short or long periods); g) failure of the current assets in service that could not be salvaged; h) reduction in performance levels of the current assets; i) increase in maintenance costs of the current assets; j) deterioration of the asset condition that represents an unacceptable risk for the required operation of the network or to the cost for the company or other areas in the event of the asset failure. Items a) to d) are generally accepted to be network growth issues and are dealt with through a network development planning process, which is not part of this research. An asset management process for current assets in service generally deals with items g) to j), which is the focus of this research.
UWA	55 The items referred above as item e) and f) are dealt with by both of those two processes depending on the size of the problem and the assets those items would impact on. The asset disposal may be initiated through a number of different activities that require the assets in service in the transmission network to be retired: a) asset replaced through the above network improvement activities that cannot be used at another location (obsolete performance, too expensive to run due to high maintenance costs, too expensive touprate to a required standard for other location); b) asset replaced after the failure in service and cannot be repaired or the repair costs would be too high; c) asset replaced due to deterioration or unsatisfactory service before its failure through an asset renewal project. The above asset disposal options review is generally combined with other activities of an asset management process for transmission network assets in service (maintenance planning, network development, operational conditions, customer supply risks). In-between those two boundary points, there are a number of other activities that are in some way relevant to the asset management process: - inspection; - servicing (maintenance); - condition monitoring; - diagnosis and repair; - failure and repair or else (disposal); - refurbishment (overhaul);
UWA	56 - modification; - replacement with relocation or disposal. Throughout the above process that transmission assets undergo during their lifetime, there is an obvious need to know one's asset inventories and their details as a basis to collect other information and to monitor the asset. Therefore, it is a paramount requirement that there should be an elaborate data acquisition process to capture data about new assets, and to properly record work on current assets until their disposal. That in turn creates the need for a number of databases to be set up in the company to enable the data recording and reporting. 5.3.2. Identification of the Process Main Functions The high level process that has been identified as fulfilling all the requirements for a proper asset management role in a transmission business leads to the need for identification of the main work functions that are or should be fully covered in that process. A specific approach towards achieving that need defines four steps to reach the required outcome: • use of all identified areas in the transmission business that have any involvement in working with the current assets; • interviewing those identified areas; • setting up a series of workshops with those areas to determine their current involvement and opinion of other areas;
UWA	57 • prepare a summary to define all essential functions and their characteristics. A summary flow-chart, as shown in Fig.5.2, has been designed as a result of that investigation." The above approach has yielded a conclusion that the work functions need to encompass the areas of asset strategy and policy, asset owner's input, maintenance criteria, management of maintenance service providers, maintenance management, performance management, recording and reporting of assets and their activities. There must be a procedure to ensure action is taken on the reported and obtained information of operational and maintenance problems and restrictions. Also, that changes and influences from network planning, input by other areas that deal with external factors, and planning of asset future role by asset owner, are covered. Underpinning that process is the provision of ongoing support and improvement in the necessary information systems and decision tools, which are procedures in themselves and will be covered in this thesis. The above findings about the identified work functions required for a complete asset management process are presented below in Sections 5.3.2.1 to 5.3.2.5, where the function requirements are described in more details. These findings are based on the previously agreed understanding that the business functions must address the full scope of the asset management model and its process in a timely manner if the model to be set up by the thesis is to meet its expectations.
UWA	61 • Investigation of assets with poor performance; • Investigation of major asset failures; • Provision of technical and specialist advice. 5.3.2.5. Asset Renewal Planning The planning work for the asset renewals includes the following activities: • Review and analysis of asset condition; • Preparation and update of the Asset Management Plan; • Review and coordination of asset renewal (repair, modification, refurbishment and replacement) and network development plans; • Preparation and update of the Asset Contingency Plan; • Implementation of recommendations from the Asset Management Plan; • Preparation of asset renewal business cases; • Capital expenditure approvals for asset replacements projects; • Maintenance expenditure approvals for other major asset works; • Management of asset repair, modification and refurbishment works. There are also other inputs into the above work functions from the following areas that will have to be accommodated properly in the new model for the asset management process: - input from asset manufacturers of the new and existing assets; - input from various areas providing own internal knowledge, such as asset management, maintenance, construction, design, testing, etc; - system planning; - system operations;
UWA	62 - asset owner function groups with inputs and instructions on corporate, legal, financial, media, environment, energy regulator and network performance requirements; - input from the other industry bodies and associations; - outcomes of internal or mixed working groups and investigations set up in the company to achieve better returns on asset investments or to increase the safety and reliability performance. 5.3.2.6 Summary of Work Function Requirements In summary, the complete model and its process will have to fully cover the following five main areas of the asset management: - asset management process and procedures, which includes company's strategy and policy at the high level, that will define how the organisation will deal with the asset management practice, organisation, resources, planning and implementation of strategy and policy, and actions on the results of the process; - asset maintenance criteria and practices, maintenance work content, maintenance work cost identification and planning, improvement strategies in maintenance policy, and standard specifications for draw down contracts; - asset maintenance planning and implementation, annual work maintenance plans and budget and cost planning, service level agreements and contracts with service providers, work and cost performance monitoring of the providers, improvement of the efficiency and effectiveness of the maintenance work and process;
UWA	63 - regular reporting and analysis of asset maintenance and asset performance, and subsequent follow-up actions based on the prescribed guidelines, including feedback to update current maintenance policy documents and to correct the network future development plans; - long-term asset management plans based on asset maintenance costs, performance, age distribution, environmental impact, regulatory requirements, critical position in the system, and future role in the network development plans. It has also become obvious that the paramount areas that need to be covered first by a complete model are clear asset strategy and policy in the company with defined approach to asset management and identified work and business functions. That should be followed by a definition of the process and procedures for all necessary activities to define roles and involvement of the business functions (maintenance and construction, asset management, network planning, design, operation, project management, procurement, finances) in the above main areas of transmission asset management 5.3.3. Development of Links Between Business Functions To achieve a dynamic and integrated asset management model it is necessary to define all links between various business functions in the asset management process as defined above. That should include requirements for individual steps and procedures in the interactions between those business functions in the asset management
UWA	64 process and the definition of the composition and timing of those interactions. The collected data would be useless without regular and properly installed representations with relevant and timely information through a reporting process using an array of defined reports. The reports are then analysed and reviewed by the proper personnel in defined responsible business functions to contribute to the company's awareness of the asset current operations, performance and well being, and assessment and planning of its future condition and purpose. Up-to-date knowledge of asset current requirements, its condition and performance (operational as well as financial), and its many future directions and expected purpose in the transmission network, as the overall system grows and subsequent operational needs change, are important and require continuous inputs throughout the asset management process. These inputs form the basis of proper decision making required by all responsible business functions within their work framework about the asset current and future role in the transmission network and its operational and maintenance needs throughout its service life. A complete and timely exchange of the feedback information about the network assets in service, its condition and reliability amongst the asset management, operational and planning business functions is the most important aspect of the overall mechanism for a proper functioning of the developed asset management model and its process.
UWA	65 The above mentioned activities must not only be fully integrated in an organisational sense, ie that all the work and relations are clearly defined and implemented, but they must all also have a known time component. That means that all the defined interchange work links have a defined time lag in which the necessary users have to implement the transferred information into their work, and then provide their own feedback to the next group(s). All the above need to be underpinned by a well-set up organisation of the transmission business and the use of engaged internal and external resources into an organisational matrix to cover all functions. Any eventual matrix of an organisational structure for the transmission business must always aim to set clear responsibilities for various aspects of the defined asset management model and its process. That should ensure that all parts of the organisational matrix have covered the defined and required structure, content and timeliness of links between the functions with their mutual responsibilities. This work has been in parallel with work from Section 5.3.2, and using the same investigation process to firstly confirm the existing interaction between the current organisational groups. The findings have been used to map out the current procedures and compare them to the requirements. The identification of the gaps has allowed then to proceed and set-up implementation of the links in full according with the model process requirements. All developed and defined required links between the relevant business functions with their contents, reviews required and their timing references
UWA	66 are presented with more details in Sections 5.4, 6.2.3, 6.4, and 7.3; and in Chapters 10, 12 and 13. 5.4. Presentation of the Developed Integrated Model Asset management is an organised process within a company that needs to be implemented to ensure that there are proper documents, process and procedures in place. They are to ensure sustainable delivery of a high service level of managed transmission assets at a reasonably low cost with assessed and known risks considered manageable and acceptable. The level should ensure a performance of the transmission network that is acceptable to the company, market and regulator. Sustainable delivery must ensure long-term profitability of the company and long term-viability of the assets themselves. The final integrated and dynamic asset management model aims to satisfy the above goals and requirements through its: • proper business functional structure, • fully dynamic and integrated process, • completeness of its initial and output documentation; • organisation of the full use and update of the developed documentation, • definition of all aspects of the required works by having the complete process covered by an elaborate procedures matrix.
UWA	61 5.4.1. Integrated Model Structure and Initial Documentation The model is based on two main activity streams defined in the Asset Management Policy to cover the above mentioned asset management requirements: a) definition and execution of maintenance and repairs of assets in service, which is given a broad term of asset maintenance management; b) monitoring of asset performance, assessment of condition, how critical is the asset position in network, and planning of necessary actions to respond to the identified asset problems (modification, refurbishment and replacement), which is given a broad term of asset renewal management. The model begins with an asset management strategy statement for the management of transmission assets, which is presented in document Asset Management Strategy in Section 6.2. It follows with a definition of aims and goals that the implemented asset management process needs to fulfil in the transmission business to achieve the above strategy statement, which is presented in document Asset Management Policy in Section 6.3. The model is then further defined and developed in documents referred to as Asset Management Process Manual and Asset Management Procedures Manual. The Asset Management Process Manual deals with the definition of the processes of the developed asset management model and its main functions (eg asset management, planning, maintenance, operations, etc) and defines
UWA	69 Those business functions could also, but not necessarily, represent names of groups in an organisational sense, but they can be performed by a number of different groups in any set up of the transmission business structure. The only important rule to follow to achieve the model benefits is to ensure that the adopted structure and its groups have clearly covered all main process work and business functions. In that way, the required process and its procedures with the relevant documentation will be clearly accountable for the functions assigned to the set-up organisational groups. The required responsible transmission business functions are described in more detail in Chapter 12. The central focus is on an asset management function, which has to have its needs and responsibilities clearly identified and visible in any adopted business organisational structure. It should also be given an overall coordination role for all asset management related activities in the business even when they are performed throughout any other area in the set-up structure. The model simplified structure outline, incorporating a general asset management process, main functions involved, their interactions, required initial and output documentation with possible output results, is presented in a flow chart in Fig.5.3. Fig.5.3 also shows links between the main business functions required for the process to succeed. The links and their content are explained in more detail in the thesis.
UWA	The most important links are to the: • transmission network planning and its network development plans, which deal with all requirements for new network assets due to the development of the transmission network; • system operations that provides ongoing information on changes in the way the network performs and operates; • asset owner function arms of finance services and business development for general business guidelines. It is important to reiterate that the new asset management model deals only with the existing assets in service in the transmission network. The process to acquire new assets to cater for new transmission network developments is dealt with by the network planning function through a separate set of rules, and that process is not covered by this research and thesis. The network planning work is influenced and determined by various factors, such as system growth due to more customers and more consumption, increases in load transfers and fault levels on the system due to such growth, and new requirements coming through from the regulators, new regulations and new standards. The model does however make extensive use of network development plans to identify all aspects that may influence the way current assets should be managed in the course of the asset management process.
UWA	74 Provision must be made for specific procedures for emergency response and follow-up actions in the event of asset failures (effecting asset repairs or using prepared contingency provisions to assist in the event of asset failures that cannot be repaired on site). Subsequent instructions are necessary to achieve proper handling of the replaced assets after the failed and non-performing assets are replaced with a new unit. This process must include a procedure for the development and upkeep of service level agreements with the maintenance service providers. The agreements should cover how the service providers will receive and execute the required maintenance work, specify ways to monitor and review performance of their work, and include a provision to accommodate regular auditing of their work management and maintenance work process, and their procedures. The asset maintenance management also includes a role of maintenance optimisation, achieved by applying various maintenance analysis techniques to the results of the reports produced on asset maintenance work. These techniques are used to analyse the assets' current and future short- term operational needs and maintenance history to assess the effectiveness and efficiency of the maintenance work and confirm the need and adequacy for the proposed maintenance work.
UWA	Those strategies also cover an analysis of risk management assessment and criteria for necessary modification and refurbishment of assets in order to ensure that assets reach their designated lifetime. The strategies also take into consideration the importance of the assets in the network, and the planned enhancements and additions of the network due to various system and external requirements. That will assist in work to define any action for or with the asset in a defined timeframe, and planning of investments into renewals of assets that are currently in service in the transmission network. A number of documents have been prepared to define the initial and output documentation covering asset assessment procedures that use the reports, their reviews, and the output results. Some of these documents are considered initial documents, such as the Business Case Analysis Manual. Other documents contain results, which are outcomes of the asset assessment procedures, and they are: - Asset Management Plan, - Business Case Studies, - Special Contingency Plans. These documents are discussed in more detail in Chapters 9 and 15.
UWA	80 • a defined asset management policy that sets out the commitment to the right process, procedures, supporting tools and planning of the necessary resources that will meet the short and long term requirements for its assets through an asset management functional model. The objective of both the above asset management strategy and asset management policy is to ensure that: • Plant performance meets current customer requirements; • Plant capacity and condition will enable customer requirements to be met in the future; • Plant faults can be rectified without jeopardising network security; • Power supply is restored quickly after faults; • Industry best-practice levels are achieved and maintained for the plant 'whole-of-life' operation costs and performance; • Long-term business plans reflect operating and capital expenditures needed to renew assets in a timely and organised manner; • Safety of employees, customers and public is protected; • Environmental impacts are acceptable; • Business can sustain long-term financial viability; • Share holder value increases. Asset management at the generic level is a set of business procedures concerned with developing, operating and maintaining the asset that delivers owner's requirements. It is about delivering the required standard of asset performance for the transmission business and its customers at the minimum overall costs while maintaining long-term asset upkeep and viability.
UWA	81 The transmission business in Western Australia first adopted an idea of asset management model development as a general approach to solve all the above issues in 1994. That strategic decision was then followed in 1995 with a review of its assets performance and asset carer functions to reach a stage that will ensure proper custodianship for its existing assets in service. It resulted in the establishment of a dedicated transmission maintenance group with the initial focus being to develop and implement a proper asset maintenance management of its primary assets, that was soon followed with a need to expand its role and embrace a wider asset management focus. Many discussions then ensued on how to approach a development of an overall asset management strategy for all its transmission assets. A variety of different available ways were explored during 1996 and 1997, including initial internal and external audits of asset management practices and comparing external studies to the internal developments. Following the above work and presentation to the senior management, an initial asset management model was proposed and then implemented in the business during 1998. The model, using and building on the experience of the initial model, was extended, with the implementation of the developed process and procedures, into a more detailed model across the whole of the transmission business during 1999 and 2000.
UWA	82 The following Sections 6.2 and 6.3 discuss the strategic principles of an asset management model as adopted by the transmission business, and describe how accountability for managing assets has been assigned throughout the business functions. 6.2. Asset Management Strategy The first step in setting-up the required framework for the development of a new model for the transmission asset management is to clearly define the company's asset management strategy. 6.2.1. Asset Management Ownership Model The key feature of the asset management ownership model presented in Fig.6.1 is the separation of the roles of the asset manager and the service provider functions within the company. In this model, the asset manager is accountable for policies and subsequent decisions about current and future roles of the asset, while the service providers are responsible for managing the resources that carry out activities on the asset, as defined and requested by policies and plans developed by the asset manager. The basic tenets of that asset management ownership model are: • Clear focus on maximising the value of the asset for the owner; • Clear separation of responsibility for managing the workforce from responsibility for managing the asset;
UWA	84 That involves optimisation of the network and asset development, utilisation, maintenance, upgrade, operation and retirement of the assets to support the asset owner's strategy of maximising return from the asset and at the same time building shareholder's value. The orientation for the service providers is to build and operate a workforce for maintenance and construction work, with a focus on work service quality and excellence, culture of market competitiveness, and continuous improvement in their work. 6.2.2. Asset Management Strategy Assets only exist to support the delivery of products and outcomes. Asset management is a structured process covering the whole life of an asset with the objective being to achieve the best possible match of the asset with the business needs. Decisions about assets must therefore be integrated by linking the asset management process with the required business outcomes andprogrammes in all other transmission business areas. The key features of the above asset management framework are: • Link with business planning process; • Service or output driven; • Structured and systematic; • Based on whole-of-life concepts. The framework for our asset management strategy to try to ensure fulfilment of the above requirements is shown in Fig.6.2.
UWA	87 Therefore, the main areas included with the asset owner are: • Business Development, providing overall business directions and requirements, including information from the energy regulator, government and local authority legislation, and open access policies; • Finance Services, providing financial guidelines, budget planning and coordination, financial reporting and other general support. 6.2.3.2. Asset Manager The asset manager is responsible for defining and enhancing the asset management process, its procedures and the relevant documentation. This covers asset maintenance and operational strategies to achieve asset performance objectives, optimising the life cycle cost of the assets to maximise the value adding to the business, monitoring asset performance, managing relevant risks, setting asset and network standards, and planning long-term asset maintenance and capital fund requirements. The decisions must be based on a life-cycle view of costs and performance, assessment of various identified risks to realise optimal capital and operating costs against minimum performance required, and achieving long-term viability of the assets and the business. The specific focus on asset management enables the development of policy, process, and procedures for the enhancement, maintenance and operation of the current asset base in such a way to deliver defined network
UWA	88 performance and to maximise shareholder's value over the life of network assets. This is an essential goal and requirement since there is substantial capital committed to the asset base and the need to maximise the regulated income derived from these assets if they are going to contribute to the economic profit of the business. Three main business functions have been set up to carry out the asset manager role in the transmission business: • Asset Management; • System Operations; • Network Planning. Asset management is responsible for the overall asset management process and its policies, standards and procedures relating to the current assets in service, including lines, substations, cables, and primary and secondary plant and control equipment. The asset management role is to manage performance and control maintenance of the installed assets in service, to initiate and subsequently to sponsor any approved asset renewal projects (modification, refurbishment and replacement). Network planning is responsible for the planning criteria and standards guiding the performance, enhancement and retirement of the transmission system according to performance levels set-up by the asset owner.
UWA	89 They undertake operational and planning analysis of the network, ensure future capability planning, and are the sponsors of the resulting network upgrade, augmentation and expansion projects. System operations are responsible for the organisation of proper functioning of the power system and the transmission network and associated assets to deliver supply to the end customer. That includes responsibility for operational reliability, security and quality of electricity supply, coordinated and controlled access to the transmission assets, and for the day-to-day operation andstewardship of the power system control and data acquisition systems and equipment that supports their activity. 6.2.3.3. Service Providers The service providers are accountable for the provision of all defined and requested maintenance and other service for the specified work documentation, for coordination of those works, and for providing those services cost-effectively and efficiently. They have to deliver the products that are market tested for value and quality to the transmission business, and need to support the asset management process with proper feedback and innovation input about the work they perform. Workforce management decisions regarding staffing, skills and productivity, union relations and bottom line margins are based on achieving flexibility, customer focus and strong cost and work management, with a view to maintaining or growing market share.
UWA	92 may result in higher long-term costs and exposure to higher liability risks. It can also result in a failure to meet customer requirements, asset owner or regulatory service standards, and breach other legal or statutory obligations. Transmission business will therefore be fully committed to the development, implementation and continuous update of such an asset management process that will ensure an effective and efficient maintenance of its existing assets and proper and timely planning of necessary resources to meet the long-term requirements for its assets. The above mentioned asset management process and its required procedures can be specified through two main activity streams: • definition and execution of maintenance and repairs of assets in service. This activity is given the broad term of asset maintenance management; • monitoring of performance, assessment of condition, critical position in service, and planning of necessary actions to respond to the identified asset problems (through modification, refurbishment and replacement). This activity is given the broad term of asset renewal management. This document provides a policy overview indicating how the transmission business should effect the above two management activities to ensure the ongoing performance and appropriate responses for the long-term requirements of its existing assets in service in the transmission network. Development of the transmission network to cater for an increase in the load and thermal ratings, fault level increases due to new generation, and through the new customer connections is the sole responsibility of the network planning.
UWA	93 The results of their studies are given in a separate set of documents covering short and long-term network development plans for the load areas. 6.3.2. Asset Management Policy The following rules have been adopted by the transmission business when dealing with requirements and application of asset management throughout the company, based on the above agreed strategy, to achieve the best results: (i) Long term asset maintenance and asset renewal plans will be prepared annually for all assets to cover necessary asset maintenance servicing, repairs, refurbishment, modifications, and replacements, and they will be based on: - asset age and condition; - asset future role in the system and potential for obsolescence; - probability of an asset failure and the consequences of such failure; - physical and system environments in which the asset operates; - realistic asset decay predictions and subsequent life-cycle costs planning; - need to ensure the long-term financial viability of the business. (ii) Investment in the existing asset infrastructure will be based on the need to: - maintain defined reliability and quality of supply to customers; - reduce servicing and operating costs; - extend the economic life of equipment; - increase return on assets; - ensure safe operation of assets;
UWA	94 - meet regulatory and environmental requirements. (iii) All proposals for major expenditure on assets will be prepared on a consistent basis using the standard project approval process. (iv) Asset maintenance will be completed for each type of equipment to: - achieve minimum maintenance costs; - ensure the condition stays within acceptable limits; - operate it at an acceptable level of risk; - meet required performance targets. Their maintenance plans will take into account the overall life cycle plan of the assets, including renewal and disposal plans, and will employ world class methodologies for its implementation. (v) Risk exposure will be identified through due diligence programmes, asset audits, analysis of performance history and other specialised risk analysis projects. Critical assets will be identified by a standard risk management procedure and classified into different risk categories to place resources where they are most needed. All risk types will be periodically assessed and will include: - statutory infringement risk; - ownership cost risk; - service performance risk; - customer impact risk; - community impact risk.

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