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01272 Dispersed generation planning using improved Hereford ranch algorithm
06
Electrical power supply and utilization (scientific, technical)
simulator for operating and validating the system off-line. The system has several novel features that differentiate it from previously developed technology and make it simple to use and operate. The system has been enveloped using a state-of-the-art expert system shell that makes it very functional and expandable for other plant control systems.
Carbon anodes for a lithium secondary battery based on polyacrylonitrile
99101262
Wu, Y. et al. J. Power Sources, 1998, 75, (2) 201-206. By using elemental analysis, X-ray powder diffraction, scanning electron microscopy and X-ray photoelectron spectroscopy carbon anode materials for a lithium secondary battery based on polyacrylonitrile (PAN) are studied. The reversible lithium capacity and charging voltage curves of carbons from PAN are affected by the heat-treatment temperature, the rate of temperature rise and the soak time. These factors lead to a change in nitrogen content, cyclization and cross-linking processes, the carbon structure and the number of micropores. As the reversible capacity reaches 426 mAh gg’ at 6Oo”C, the lower the rate of temperature rise, the higher the reversible capacity. The addition of phosphoric acid can favour the cyclization process of PAN and can increase the number of micropores in the resulting carbon. It can also act as a setting agent for graphene molecules and can improve the regularity of the carbon structure. In addition, the doped phosphorus is bonded with carbon and oxygen and dispersed homogeneously in the bulk carbon structure, this can enhance the reversible capacity above and below 0.9 V.
Characterization of direct methanol fuel cells by ac 99101263 impedance spectroscopy
Mueller, .I. T. and Urban, P. M. Journal of PowerSources, 1998, 75, (l), 139-143. In direct methanol fuel cells (DMFC), the processes taking place are characterized by ac impedance spectroscopy under realistic operating conditions. This method is a valuable diagnostic tool for DMFC development, allowing the separate examination of anode kinetics, anode mass transport, cathode kinetics, cathode mass transport and membrane conductivity.
Coalbed methane/fuel 99101264 electric power generation
cell operation for direct
Haskew, T. A. et al. Proc. Gas Technol. Symp., 1996, 451-460. The feasibility for installing a 200 kW phosphoric acid fuel cell at a large underground coal mine located in the Black Warrior Basin of Alabama was determined in this investigation. Assurance of supply, variation of coal-bed methane quality and economic feasibility were all studied. The fuel cell can be operated directly from variable-quality coal-bed methane produced from underground mining. Waste heat from the fuel cell can be used in the mine coal dryer, allowing a portion of the coal normally consumed in the dryer to be sold. If available, excess electric power can be sold to the public utility grid. If it is to be competitive, an energy cost of approximately $O.OS/kWh is necessary for the direct generation of electric power from a coal-bed methane/fuel cell system.
99101265 teries
Coke vs. graphite as anodes for lithium-ion bat-
Shi, H. J. Power Sources, 1998, 75, (l), 64-72. This paper investigates the respective rapid charge capabilities for graphite and coke for use in lithium-ion electrochemical cells. Lithium-ion cells with graphite anodes showed a poor ability to be rapidly charged due to the nature of the lithium intercalation process associated with graphite. By contrast, lithium-ion cells with coke anodes showed a much better quickcharge capability compared to that of graphite cells. In this paper, a series of experiments was carried out in order to characterize the difference in quick-charge capability between graphite and coke anode cells. Lithium manganese oxide was used as the cathode material. The simulation results supported the experimental observation that, during high-rate charging, coke has a superior ability to quickly distribute the lithium into the anode.
Commercial cokes and graphites as anode materi99101266 als for lithium-ion cells
Derwin, D. J. er al. Mater. Res. Sot. Symp. Proc., 1998, 496, 575-580. An investigation was carried out on several types of carbonaceous materials for lithium ion intercalation. These commercially available cokes, graphitized cokes and graphites have a wide range of physical and chemical properties. The coke materials were investigated in propylene carbonate based electrolytes and the graphitic materials were studied in ethylene carbonate/di-Me solutions to prevent exfoliation. The reversible capacities of disordered cokes are below 230 mAh/g and those for many highly ordered synthetic and natural graphites approached 372 mAh/g (LiC& The irreversible capacity losses vary between 15 to as much as 200% of reversible capacities for various types of carbon. Heat treated cokes (with the average particle size of 10 pm) showed marked improvements in reversible capacity for lithium intercalation. The electrochemical characteristics are correlated with data obtained from SEM high resolution transmission electron microscopy (TEM), X-ray diffraction and BET surface area analysis. A discussion takes place on the electrochemical performance, availability, cost and manufacture ability of these commercial carbons.
126 Fuel and Energy Abstracts
March 1999
99101267 Crystal structures of mixed-conducting present in the Sr-Fe-Co-O system
oxides
Hodges, J. P. et al. Mater. Res. Sec. Symp. Proc., 1998, 496, 173-178. Mixed-conducting ceramic oxides have several potential applications, including solid-oxide fuel cells, rechargeable batteries, gas sensors and oxygen-permeable membranes. Several perovskite-derived mixed strontium-iron
Design of a robust power system stabilizer using 99101266 fuuy logic for a multi-machine power system
Lakshmi, P. and Abdullah Khan, M. Electric Power Sysfems Research. 1998, 47, (1) 39-46. A design procedure for a fuzzy logic based power system stabilizer (FPSS) is presented and the robustness of the FPSS for a multi-machine power system is investigated. Speed deviation of synchronous generator and its derivative are chosen as the input signals to the FPSS. A two area, five generator power system is used to illustrate the robustness of the FPSS. A normalized sum-squared deviation (NSSD) index is used for designing the FPSS and demonstrating its robustness. The results of non-linear simulation tests for different disturbances are discussed.
Development of a concept for production and use 99101269 of coal fuel Deberdeev, I. K. and Linev, B. I. Ugol’, 1998, (1) 52-55. (In Russian) In Russia, the quality of coal used for heat generation and electric power should be improved by both reversing the trend of deteriorating quality of out-of-the-mine coal and benciiciation of all coals used by utilities.
Development of a low-cost oxy-hydrogen bio-fuel cell for generation of electricity using Nostoc as a source of hydrogen
99101270
Dawar, S. et al. Energy Research, 1998, 22, (12), 1019-1028. An oxy-hydrogen bio-fuel cell, based on a carbon-carbon electrode has been developed. Carbon powder mixed with polyvinylalcohol as a binder created the electrode pellets. The electrolyte was 30% KOH. The anode was charged with cobalt-aluminium spine1 mixed oxide at 700°C. A potential heterocystous blue-green alga of Nostoc spp. was used for hydrogen production and electrical energy generation for the cyanobacterial bioreactor. The hydrogen generation efficiency of the algae by employing various nutrient enrichment techniques. The free cell algal reactor was attached to the fuel cell at the anode end for hydrogen gas input, of which one litre generated about 300 mV of voltage and 100 mA of current. The authors suggest that these findings on the development of a low cost fuel cell with high efficiency of current output may be helpful in commercializing this technology.
99101271 Discharge-charge characteristics and performance of LilFeOOH (an) battery with PAN-based polymer electrolyte
Hwang, K.S. et al. .I. Power Sources, 1998, 75, (l), 13-18. This paper investigates the discharge-charge characteristics and performance of a Li/FeOOH(an) solid polymer battery. The cell uses a cathode of amorphous FeOOH with aniline derivatives (FeOOH(an)) and a polyacrylonitrile-based solid polymer electrolyte. The ionic conductivity of the electrolyte sample used for electrochemical measurements is 1.6 x 10-s R-’ cm-’ at room temperature. Its anodic stability is above 4.5 V. Variations of impedance parameters and the diffusion coefficient are investigated during the first discharge-charge. From the results of these measurements, it is concluded that the structure of FeOOH(an) is deformed by Li+ ion insertion/extraction. The electrochemical redox reaction of FeOOH(an) is investigated by cyclic voltammetry. In the potential range 2.0 to - 4.0 V, the first discharge-charge is irreversible. Reversible cycling processes take place thereafter.
99101272 Dispersed generation Hereford ranch algorithm
planning
using improved
Kim, J. 0. et al. Electric Power Systems Research, 1998, 47, (l), 47-55. Based on Hereford ranch algorithm (HRA) in a subtransmission system, this paper presents a new approach to dispersed generation planning. Dispersed generations could be photovoltaic cells, wind generation, battery storage, fuel cell, etc. A method to optimally locate such generation in a meshed network for maximizing the potential benefits is outlined using HRA and its improvement in this paper. The benefit expressed as a performance index is minimization of losses. The proposed method was tested for several sample power systems with 6, 14 and 30 bus types. Also, the results of suggested algorithm are compared with those of classical genetic algorithm and conventional second-order method to show its effectiveness.
Electrical power supply and utilization (scientific, technical)
simulator for operating and validating the system off-line. The system has several novel features that differentiate it from previously developed technology and make it simple to use and operate. The system has been enveloped using a state-of-the-art expert system shell that makes it very functional and expandable for other plant control systems.
Carbon anodes for a lithium secondary battery based on polyacrylonitrile
99101262
Wu, Y. et al. J. Power Sources, 1998, 75, (2) 201-206. By using elemental analysis, X-ray powder diffraction, scanning electron microscopy and X-ray photoelectron spectroscopy carbon anode materials for a lithium secondary battery based on polyacrylonitrile (PAN) are studied. The reversible lithium capacity and charging voltage curves of carbons from PAN are affected by the heat-treatment temperature, the rate of temperature rise and the soak time. These factors lead to a change in nitrogen content, cyclization and cross-linking processes, the carbon structure and the number of micropores. As the reversible capacity reaches 426 mAh gg’ at 6Oo”C, the lower the rate of temperature rise, the higher the reversible capacity. The addition of phosphoric acid can favour the cyclization process of PAN and can increase the number of micropores in the resulting carbon. It can also act as a setting agent for graphene molecules and can improve the regularity of the carbon structure. In addition, the doped phosphorus is bonded with carbon and oxygen and dispersed homogeneously in the bulk carbon structure, this can enhance the reversible capacity above and below 0.9 V.
Characterization of direct methanol fuel cells by ac 99101263 impedance spectroscopy
Mueller, .I. T. and Urban, P. M. Journal of PowerSources, 1998, 75, (l), 139-143. In direct methanol fuel cells (DMFC), the processes taking place are characterized by ac impedance spectroscopy under realistic operating conditions. This method is a valuable diagnostic tool for DMFC development, allowing the separate examination of anode kinetics, anode mass transport, cathode kinetics, cathode mass transport and membrane conductivity.
Coalbed methane/fuel 99101264 electric power generation
cell operation for direct
Haskew, T. A. et al. Proc. Gas Technol. Symp., 1996, 451-460. The feasibility for installing a 200 kW phosphoric acid fuel cell at a large underground coal mine located in the Black Warrior Basin of Alabama was determined in this investigation. Assurance of supply, variation of coal-bed methane quality and economic feasibility were all studied. The fuel cell can be operated directly from variable-quality coal-bed methane produced from underground mining. Waste heat from the fuel cell can be used in the mine coal dryer, allowing a portion of the coal normally consumed in the dryer to be sold. If available, excess electric power can be sold to the public utility grid. If it is to be competitive, an energy cost of approximately $O.OS/kWh is necessary for the direct generation of electric power from a coal-bed methane/fuel cell system.
99101265 teries
Coke vs. graphite as anodes for lithium-ion bat-
Shi, H. J. Power Sources, 1998, 75, (l), 64-72. This paper investigates the respective rapid charge capabilities for graphite and coke for use in lithium-ion electrochemical cells. Lithium-ion cells with graphite anodes showed a poor ability to be rapidly charged due to the nature of the lithium intercalation process associated with graphite. By contrast, lithium-ion cells with coke anodes showed a much better quickcharge capability compared to that of graphite cells. In this paper, a series of experiments was carried out in order to characterize the difference in quick-charge capability between graphite and coke anode cells. Lithium manganese oxide was used as the cathode material. The simulation results supported the experimental observation that, during high-rate charging, coke has a superior ability to quickly distribute the lithium into the anode.
Commercial cokes and graphites as anode materi99101266 als for lithium-ion cells
Derwin, D. J. er al. Mater. Res. Sot. Symp. Proc., 1998, 496, 575-580. An investigation was carried out on several types of carbonaceous materials for lithium ion intercalation. These commercially available cokes, graphitized cokes and graphites have a wide range of physical and chemical properties. The coke materials were investigated in propylene carbonate based electrolytes and the graphitic materials were studied in ethylene carbonate/di-Me solutions to prevent exfoliation. The reversible capacities of disordered cokes are below 230 mAh/g and those for many highly ordered synthetic and natural graphites approached 372 mAh/g (LiC& The irreversible capacity losses vary between 15 to as much as 200% of reversible capacities for various types of carbon. Heat treated cokes (with the average particle size of 10 pm) showed marked improvements in reversible capacity for lithium intercalation. The electrochemical characteristics are correlated with data obtained from SEM high resolution transmission electron microscopy (TEM), X-ray diffraction and BET surface area analysis. A discussion takes place on the electrochemical performance, availability, cost and manufacture ability of these commercial carbons.
126 Fuel and Energy Abstracts
March 1999
99101267 Crystal structures of mixed-conducting present in the Sr-Fe-Co-O system
oxides
Hodges, J. P. et al. Mater. Res. Sec. Symp. Proc., 1998, 496, 173-178. Mixed-conducting ceramic oxides have several potential applications, including solid-oxide fuel cells, rechargeable batteries, gas sensors and oxygen-permeable membranes. Several perovskite-derived mixed strontium-iron
Design of a robust power system stabilizer using 99101266 fuuy logic for a multi-machine power system
Lakshmi, P. and Abdullah Khan, M. Electric Power Sysfems Research. 1998, 47, (1) 39-46. A design procedure for a fuzzy logic based power system stabilizer (FPSS) is presented and the robustness of the FPSS for a multi-machine power system is investigated. Speed deviation of synchronous generator and its derivative are chosen as the input signals to the FPSS. A two area, five generator power system is used to illustrate the robustness of the FPSS. A normalized sum-squared deviation (NSSD) index is used for designing the FPSS and demonstrating its robustness. The results of non-linear simulation tests for different disturbances are discussed.
Development of a concept for production and use 99101269 of coal fuel Deberdeev, I. K. and Linev, B. I. Ugol’, 1998, (1) 52-55. (In Russian) In Russia, the quality of coal used for heat generation and electric power should be improved by both reversing the trend of deteriorating quality of out-of-the-mine coal and benciiciation of all coals used by utilities.
Development of a low-cost oxy-hydrogen bio-fuel cell for generation of electricity using Nostoc as a source of hydrogen
99101270
Dawar, S. et al. Energy Research, 1998, 22, (12), 1019-1028. An oxy-hydrogen bio-fuel cell, based on a carbon-carbon electrode has been developed. Carbon powder mixed with polyvinylalcohol as a binder created the electrode pellets. The electrolyte was 30% KOH. The anode was charged with cobalt-aluminium spine1 mixed oxide at 700°C. A potential heterocystous blue-green alga of Nostoc spp. was used for hydrogen production and electrical energy generation for the cyanobacterial bioreactor. The hydrogen generation efficiency of the algae by employing various nutrient enrichment techniques. The free cell algal reactor was attached to the fuel cell at the anode end for hydrogen gas input, of which one litre generated about 300 mV of voltage and 100 mA of current. The authors suggest that these findings on the development of a low cost fuel cell with high efficiency of current output may be helpful in commercializing this technology.
99101271 Discharge-charge characteristics and performance of LilFeOOH (an) battery with PAN-based polymer electrolyte
Hwang, K.S. et al. .I. Power Sources, 1998, 75, (l), 13-18. This paper investigates the discharge-charge characteristics and performance of a Li/FeOOH(an) solid polymer battery. The cell uses a cathode of amorphous FeOOH with aniline derivatives (FeOOH(an)) and a polyacrylonitrile-based solid polymer electrolyte. The ionic conductivity of the electrolyte sample used for electrochemical measurements is 1.6 x 10-s R-’ cm-’ at room temperature. Its anodic stability is above 4.5 V. Variations of impedance parameters and the diffusion coefficient are investigated during the first discharge-charge. From the results of these measurements, it is concluded that the structure of FeOOH(an) is deformed by Li+ ion insertion/extraction. The electrochemical redox reaction of FeOOH(an) is investigated by cyclic voltammetry. In the potential range 2.0 to - 4.0 V, the first discharge-charge is irreversible. Reversible cycling processes take place thereafter.
99101272 Dispersed generation Hereford ranch algorithm
planning
using improved
Kim, J. 0. et al. Electric Power Systems Research, 1998, 47, (l), 47-55. Based on Hereford ranch algorithm (HRA) in a subtransmission system, this paper presents a new approach to dispersed generation planning. Dispersed generations could be photovoltaic cells, wind generation, battery storage, fuel cell, etc. A method to optimally locate such generation in a meshed network for maximizing the potential benefits is outlined using HRA and its improvement in this paper. The benefit expressed as a performance index is minimization of losses. The proposed method was tested for several sample power systems with 6, 14 and 30 bus types. Also, the results of suggested algorithm are compared with those of classical genetic algorithm and conventional second-order method to show its effectiveness.