The Experts below are selected from a list of 297 Experts worldwide ranked by ideXlab platform
K. K. Hansen - One of the best experts on this subject based on the ideXlab platform.
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Hybrid direct carbon Fuel cells and their reaction mechanisms—a review
Journal of Solid State Electrochemistry, 2014Co-Authors: L. Deleebeeck, K. K. HansenAbstract:As coal is expected to continue to dominate power generation demands worldwide, it is advisable to pursue the development of more efficient coal power generation technologies. Fuel cells show a much higher Fuel Utilization Efficiency, emit fewer pollutants (NO_ x , SO_ x ), and are more easily combined with carbon capture and storage (CCS) due to the high purity of CO_2 emitted in the exhaust gas. Direct carbon (or coal) Fuel cells (DCFCs) are directly fed with solid carbon to the anode chamber. The Fuel cell converts the carbon at the anode and the oxygen at the cathode into electricity, heat and reaction products. The use of an external gasifier and a Fuel cell operating on syngas (e.g. integrated gasification Fuel cells) is briefly discussed for comparative purposes. A wide array of DCFC types have been investigated over the last 20 years. Here, the diversity of pre-commercialization DCFC research efforts is discussed on the Fuel cell stack and system levels. The range of DCFC types can be roughly broken down into four Fuel cell types: aqueous hydroxide, molten hydroxide, molten carbonate and solid oxide Fuel cells. Emphasis is placed on the electrochemical reactions occurring at the anode and the proposed mechanism(s) of these reactions for molten carbonate, solid oxide and hybrid direct carbon Fuel cells. Additionally, the criteria of choosing the ‘best’ DCFC technology is explored, including system design (continuous supply of solid Fuel), performance (power density, Efficiency), environmental burden (fresh water consumed, solid waste produced, CO_2 emitted, ease of combination with CCS) and economics (levelized cost of electricity).
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Hybrid direct carbon Fuel cells and their reaction mechanisms - a review
Journal of Solid State Electrochemistry, 2013Co-Authors: L. Deleebeeck, K. K. HansenAbstract:As coal is expected to continue to dominate power generation demands worldwide, it is advisable to pursue the development of more efficient coal power generation technologies. Fuel cells show a much higher Fuel Utilization Efficiency, emit fewer pollutants (NOx, SOx), and are more easily combined with carbon capture and storage (CCS) due to the high purity of CO2 emitted in the exhaust gas. Direct carbon (or coal) Fuel cells (DCFCs) are directly fed with solid carbon to the anode chamber. The Fuel cell converts the carbon at the anode and the oxygen at the cathode into electricity, heat and reaction products. The use of an external gasifier and a Fuel cell operating on syngas (e.g. integrated gasification Fuel cells) is briefly discussed for comparative purposes. A wide array of DCFC types have been investigated over the last 20 years. Here, the diversity of pre-commercialization DCFC research efforts is discussed on the Fuel cell stack and system levels. The range of DCFC types can be roughly broken down into four Fuel cell types: aqueous hydroxide, molten hydroxide, molten carbonate and solid oxide Fuel cells. Emphasis is placed on the electrochemical reactions occurring at the anode and the proposed mechanism(s) of these reactions for molten carbonate, solid oxide and hybrid direct carbon Fuel cells. Additionally, the criteria of choosing the ‘best’ DCFC technology is explored, including system design (continuous supply of solid Fuel), performance (power density, Efficiency), environmental burden (fresh water consumed, solid waste produced, CO2 emitted, ease of combination with CCS) and economics (levelized cost of electricity).
Feridun Hamdullahpur - One of the best experts on this subject based on the ideXlab platform.
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energy and exergy analyses of a biomass trigeneration system using an organic rankine cycle
Energy, 2012Co-Authors: Ibrahim Dincer, Fahad A Alsulaiman, Feridun HamdullahpurAbstract:In this study, energy and exergy analyses of a biomass trigeneration system using an organic Rankine cycle (ORC) are presented. Four cases are considered for analysis: electrical-power, cooling-cogeneration, heating-cogeneration and trigeneration cases. The results obtained reveal that the best performance of the trigeneration system considered can be obtained with the lowest ORC evaporator pinch temperature considered, Tpp = 20 K, and the lowest ORC minimum temperature, T9 = 345 K. In addition, this study reveals that there is a significant improvement when trigeneration is used as compared to only electrical power production. This study demonstrates that the Fuel Utilization Efficiency increases, in average, from 12% for electrical power to 88% for trigeneration. Moreover, the maximum exergy Efficiency of the ORC is 13% and, when trigeneration is used, it increases to 28%. Furthermore, this study reveals that the electrical to cooling ratio can be controlled through changing the ORC evaporator pinch point temperature and/or the pump inlet temperature. In addition, the study reveals that the biomass burner and the ORC evaporator are the main two sources of exergy destruction. The biomass burner contributes to 55% of the total destructed exergy whereas the ORC evaporator contributes to 38% of the total destructed exergy.
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Modeling of an integrated two-stage biomass gasifier and solid oxide Fuel cell system
Biomass and Bioenergy, 2012Co-Authors: C. Ozgur Colpan, Alan S. Fung, Feridun HamdullahpurAbstract:Abstract A new conceptual integrated two-stage biomass gasifier and solid oxide Fuel cell (SOFC) system is proposed and a multi-physics model for predicting the performance of this system is developed. A method coupling the modeling equations of a quasi 2-D model for SOFC, a 1-D model for pyrolysis reactor, and 0-D model for the remaining components is applied. Several parametric studies are conducted using the model developed. With the main objective of operating this system being maximizing the net power output, the results for the parametric studies conducted show that the number of SOFC stacks, the mass ratio of air to steam entering the gasifier, and the temperature of the pre-heated air entering the gasifier should be taken as high as possible; whereas the moisture ratio of the wet biomass should be minimized; and there is an optimum point for the rotational speed of the pyrolysis reactor. For the considered input data and the range of parameters studied, the maximum net power output of the system is found to be 93 kW. At this condition, the useful heat output, the electrical Efficiency of the system, and the Fuel Utilization Efficiency are calculated as 71 kW, 25%, and 44%, respectively.
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effect of gasification agent on the performance of solid oxide Fuel cell and biomass gasification systems
International Journal of Hydrogen Energy, 2010Co-Authors: Ozgur C. Colpan, Feridun Hamdullahpur, Ibrahim DincerAbstract:Abstract In this paper, an integrated solid oxide Fuel cell (SOFC) and biomass gasification system is modeled to study the effect of gasification agent (air, enriched oxygen and steam) on its performance. In the present modeling, a heat transfer model for SOFC and thermodynamic models for the rest of the components are used. In addition, exergy balances are written for the system components. The results show that using steam as the gasification agent yields the highest electrical Efficiency (41.8%), power-to-heat ratio (4.649), and exergetic Efficiency (39.1%), but the lowest Fuel Utilization Efficiency (50.8%). In addition, the exergy destruction is found to be the highest at the gasifier for the air and enriched oxygen gasification cases and the heat exchanger that supplies heat to the air entering the SOFC for the steam gasification case.
Aloke Kumar Ghoshal - One of the best experts on this subject based on the ideXlab platform.
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Performance analysis of solid oxide Fuel cell using reformed Fuel
International Journal of Hydrogen Energy, 2013Co-Authors: J.k. Verma, Anil Verma, Aloke Kumar GhoshalAbstract:Abstract Fuelling SOFC with reformed Fuel can be beneficial due to it being cheaper compared to pure hydrogen. A biomass Fuel can be easily modeled as a reformed Fuel, as it can be converted into H 2 and CO using gasification or biodegradation, the main composition of product from a reformer. Hence in this study it is assumed that feed to the Fuel cell contains only H 2 and CO. A closed parametric model is formulated. Performance is analyzed with changes in temperature, pressure and Fuel ratio; considering the possible voltage losses, like ohmic, activation, mass transfer and Fuel crossover. Performance curves consisting of operating voltage, Fuel Utilization, Efficiency, power density and current density are developed for both pure hydrogen and mixture of CO and H 2 . Variations of open circuit voltage with temperature, power density with current density, operating voltage with current density and maximum power density with Fuel Utilization are also evaluated.
Fei Fei Dong - One of the best experts on this subject based on the ideXlab platform.
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High performance of protonic solid oxide Fuel cell with BaCo0.7Fe0.22Sc0.08O3−δ electrode
International Journal of Hydrogen Energy, 2017Co-Authors: Rong Hua Yuan, Fei Fei DongAbstract:Abstract Solid oxide Fuel cells (SOFCs) have attracted tremendous attention for their combination of environmental power generation and Fuel flexibility. Proton conducting SOFCs (P-SOFCs) demonstrate advantages over oxygen-ion conducting SOFCs, such as less activation energies on ionic transport and higher Fuel Utilization Efficiency. Central to the devices is a suitable cathode with high catalytic activity. Herein, a cubic perovskite BaCo 0.7 Fe 0.22 Sc 0.08 O 3−δ (BCFSc) has been applied as the cathode in proton-conducting solid state Fuel cell (SOFC) with BaZr 0.1 Ce 0.7 Y 0.2 O 3−δ (BZCY) electrolyte. Peak power densities of 760, 591, 452 and 318 mW cm −2 are obtained at 650, 600, 550 and 500 °C with humidified hydrogen as the Fuel and air as the oxidant. A low polarization resistance of 0.05 Ω cm 2 under open circuit at 650 °C is observed.
L. Deleebeeck - One of the best experts on this subject based on the ideXlab platform.
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Hybrid direct carbon Fuel cells and their reaction mechanisms—a review
Journal of Solid State Electrochemistry, 2014Co-Authors: L. Deleebeeck, K. K. HansenAbstract:As coal is expected to continue to dominate power generation demands worldwide, it is advisable to pursue the development of more efficient coal power generation technologies. Fuel cells show a much higher Fuel Utilization Efficiency, emit fewer pollutants (NO_ x , SO_ x ), and are more easily combined with carbon capture and storage (CCS) due to the high purity of CO_2 emitted in the exhaust gas. Direct carbon (or coal) Fuel cells (DCFCs) are directly fed with solid carbon to the anode chamber. The Fuel cell converts the carbon at the anode and the oxygen at the cathode into electricity, heat and reaction products. The use of an external gasifier and a Fuel cell operating on syngas (e.g. integrated gasification Fuel cells) is briefly discussed for comparative purposes. A wide array of DCFC types have been investigated over the last 20 years. Here, the diversity of pre-commercialization DCFC research efforts is discussed on the Fuel cell stack and system levels. The range of DCFC types can be roughly broken down into four Fuel cell types: aqueous hydroxide, molten hydroxide, molten carbonate and solid oxide Fuel cells. Emphasis is placed on the electrochemical reactions occurring at the anode and the proposed mechanism(s) of these reactions for molten carbonate, solid oxide and hybrid direct carbon Fuel cells. Additionally, the criteria of choosing the ‘best’ DCFC technology is explored, including system design (continuous supply of solid Fuel), performance (power density, Efficiency), environmental burden (fresh water consumed, solid waste produced, CO_2 emitted, ease of combination with CCS) and economics (levelized cost of electricity).
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Hybrid direct carbon Fuel cells and their reaction mechanisms - a review
Journal of Solid State Electrochemistry, 2013Co-Authors: L. Deleebeeck, K. K. HansenAbstract:As coal is expected to continue to dominate power generation demands worldwide, it is advisable to pursue the development of more efficient coal power generation technologies. Fuel cells show a much higher Fuel Utilization Efficiency, emit fewer pollutants (NOx, SOx), and are more easily combined with carbon capture and storage (CCS) due to the high purity of CO2 emitted in the exhaust gas. Direct carbon (or coal) Fuel cells (DCFCs) are directly fed with solid carbon to the anode chamber. The Fuel cell converts the carbon at the anode and the oxygen at the cathode into electricity, heat and reaction products. The use of an external gasifier and a Fuel cell operating on syngas (e.g. integrated gasification Fuel cells) is briefly discussed for comparative purposes. A wide array of DCFC types have been investigated over the last 20 years. Here, the diversity of pre-commercialization DCFC research efforts is discussed on the Fuel cell stack and system levels. The range of DCFC types can be roughly broken down into four Fuel cell types: aqueous hydroxide, molten hydroxide, molten carbonate and solid oxide Fuel cells. Emphasis is placed on the electrochemical reactions occurring at the anode and the proposed mechanism(s) of these reactions for molten carbonate, solid oxide and hybrid direct carbon Fuel cells. Additionally, the criteria of choosing the ‘best’ DCFC technology is explored, including system design (continuous supply of solid Fuel), performance (power density, Efficiency), environmental burden (fresh water consumed, solid waste produced, CO2 emitted, ease of combination with CCS) and economics (levelized cost of electricity).
