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Sample records for 40-kw fuel-cell power

  1. The 40-kw field test power plant modification and development, phase 2

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Progression on the design and development of a 40 KW fuel cell system for on-site installation for providing both thermal and electrical power is reported. Development of the steam reformer fuel processor, power section, inverter, control system, and thermal management and water treatment systems is described.

  2. Aircraft Fuel Cell Power Systems

    NASA Technical Reports Server (NTRS)

    Needham, Robert

    2004-01-01

    In recent years, fuel cells have been explored for use in aircraft. While the weight and size of fuel cells allows only the smallest of aircraft to use fuel cells for their primary engines, fuel cells have showed promise for use as auxiliary power units (APUs), which power aircraft accessories and serve as an electrical backup in case of an engine failure. Fuel cell MUS are both more efficient and emit fewer pollutants. However, sea-level fuel cells need modifications to be properly used in aircraft applications. At high altitudes, the ambient air has a much lower pressure than at sea level, which makes it much more difficult to get air into the fuel cell to react and produce electricity. Compressors can be used to pressurize the air, but this leads to added weight, volume, and power usage, all of which are undesirable things. Another problem is that fuel cells require hydrogen to create electricity, and ever since the Hindenburg burst into flames, aircraft carrying large quantities of hydrogen have not been in high demand. However, jet fuel is a hydrocarbon, so it is possible to reform it into hydrogen. Since jet fuel is already used to power conventional APUs, it is very convenient to use this to generate the hydrogen for fuel-cell-based APUs. Fuel cells also tend to get large and heavy when used for applications that require a large amount of power. Reducing the size and weight becomes especially beneficial when it comes to fuel cells for aircraft. My goal this summer is to work on several aspects of Aircraft Fuel Cell Power System project. My first goal is to perform checks on a newly built injector rig designed to test different catalysts to determine the best setup for reforming Jet-A fuel into hydrogen. These checks include testing various thermocouples, transmitters, and transducers, as well making sure that the rig was actually built to the design specifications. These checks will help to ensure that the rig will operate properly and give correct results

  3. Fuel Cell Powered Lift Truck

    SciTech Connect

    Moulden, Steve

    2015-08-20

    This project, entitled “Recovery Act: Fuel Cell-Powered Lift Truck Sysco (Houston) Fleet Deployment”, was in response to DOE funding opportunity announcement DE-PS36-08GO98009, Topic 7B, which promotes the deployment of fuel cell powered material handling equipment in large, multi-shift distribution centers. This project promoted large-volume commercialdeployments and helped to create a market pull for material handling equipment (MHE) powered fuel cell systems. Specific outcomes and benefits involved the proliferation of fuel cell systems in 5-to 20-kW lift trucks at a high-profile, real-world site that demonstrated the benefits of fuel cell technology and served as a focal point for other nascent customers. The project allowed for the creation of expertise in providing service and support for MHE fuel cell powered systems, growth of existing product manufacturing expertise, and promoted existing fuel cell system and component companies. The project also stimulated other MHE fleet conversions helping to speed the adoption of fuel cell systems and hydrogen fueling technology. This document also contains the lessons learned during the project in order to communicate the successes and difficulties experienced, which could potentially assist others planning similar projects.

  4. 1986 fuel cell seminar: Program and abstracts

    SciTech Connect

    1986-10-01

    Ninety nine brief papers are arranged under the following session headings: gas industry's 40 kw program, solid oxide fuel cell technology, phosphoric acid fuel cell technology, molten carbonate fuel cell technology, phosphoric acid fuel cell systems, power plants technology, fuel cell power plant designs, unconventional fuels, fuel cell application and economic assessments, and plans for commerical development. The papers are processed separately for the data base. (DLC)

  5. Water reactive hydrogen fuel cell power system

    DOEpatents

    Wallace, Andrew P; Melack, John M; Lefenfeld, Michael

    2014-11-25

    A water reactive hydrogen fueled power system includes devices and methods to combine reactant fuel materials and aqueous solutions to generate hydrogen. The generated hydrogen is converted in a fuel cell to provide electricity. The water reactive hydrogen fueled power system includes a fuel cell, a water feed tray, and a fuel cartridge to generate power for portable power electronics. The removable fuel cartridge is encompassed by the water feed tray and fuel cell. The water feed tray is refillable with water by a user. The water is then transferred from the water feed tray into the fuel cartridge to generate hydrogen for the fuel cell which then produces power for the user.

  6. Water reactive hydrogen fuel cell power system

    DOEpatents

    Wallace, Andrew P; Melack, John M; Lefenfeld, Michael

    2014-01-21

    A water reactive hydrogen fueled power system includes devices and methods to combine reactant fuel materials and aqueous solutions to generate hydrogen. The generated hydrogen is converted in a fuel cell to provide electricity. The water reactive hydrogen fueled power system includes a fuel cell, a water feed tray, and a fuel cartridge to generate power for portable power electronics. The removable fuel cartridge is encompassed by the water feed tray and fuel cell. The water feed tray is refillable with water by a user. The water is then transferred from the water feed tray into a fuel cartridge to generate hydrogen for the fuel cell which then produces power for the user.

  7. Fuel-cell-powered golf cart

    SciTech Connect

    Bobbett, R.E.; McCormick, J.B.; Lynn, D.K.; Kerwin, W.J.; Derouin, C.R.; Salazar, P.H.

    1980-01-01

    The implementation of a battery/fuel-cell-powered golf cart test bed designed to verify computer simulations and to gain operational experience with a fuel cell in a vehicular environment is described. A technically untrained driver can easily operate the golf cart because the motor and fuel cell controllers automatically sense and execute the appropriate on/off sequencing. A voltage imbalance circuit and a throttle compress circuit were developed that are directly applicable to electric vehicles in general.

  8. DIRECT FUEL/CELL/TURBINE POWER PLANT

    SciTech Connect

    Hossein Ghezel-Ayagh

    2004-05-01

    This report includes the progress in development of Direct FuelCell/Turbine{reg_sign} (DFC/T{reg_sign}) power plants for generation of clean power at very high efficiencies. The DFC/T power system is based on an indirectly heated gas turbine to supplement fuel cell generated power. The DFC/T power generation concept extends the high efficiency of the fuel cell by utilizing the fuel cell's byproduct heat in a Brayton cycle. Features of the DFC/T system include: electrical efficiencies of up to 75% on natural gas, 60% on coal gas, minimal emissions, simplicity in design, direct reforming internal to the fuel cell, reduced carbon dioxide release to the environment, and potential cost competitiveness with existing combined cycle power plants. FCE successfully completed testing of the pre-alpha DFC/T hybrid power plant. This power plant was constructed by integration of a 250kW fuel cell stack and a microturbine. The tests of the cascaded fuel cell concept for achieving high fuel utilizations were completed. The tests demonstrated that the concept results in higher power plant efficiency. Also, the preliminary design of a 40 MW power plant including the key equipment layout and the site plan was completed.

  9. Fuel cell electric power production

    DOEpatents

    Hwang, Herng-Shinn; Heck, Ronald M.; Yarrington, Robert M.

    1985-01-01

    A process for generating electricity from a fuel cell includes generating a hydrogen-rich gas as the fuel for the fuel cell by treating a hydrocarbon feed, which may be a normally liquid feed, in an autothermal reformer utilizing a first monolithic catalyst zone having palladium and platinum catalytic components therein and a second, platinum group metal steam reforming catalyst. Air is used as the oxidant in the hydrocarbon reforming zone and a low oxygen to carbon ratio is maintained to control the amount of dilution of the hydrogen-rich gas with nitrogen of the air without sustaining an insupportable amount of carbon deposition on the catalyst. Anode vent gas may be utilized as the fuel to preheat the inlet stream to the reformer. The fuel cell and the reformer are preferably operated at elevated pressures, up to about a pressure of 150 psia for the fuel cell.

  10. Fuel cell power system for utility vehicle

    SciTech Connect

    Graham, M.; Barbir, F.; Marken, F.; Nadal, M.

    1996-12-31

    Based on the experience of designing and building the Green Car, a fuel cell/battery hybrid vehicle, and Genesis, a hydrogen/oxygen fuel cell powered transporter, Energy Partners has developed a fuel cell power system for propulsion of an off-road utility vehicle. A 10 kW hydrogen/air fuel cell stack has been developed as a prototype for future mass production. The main features of this stack are discussed in this paper. Design considerations and selection criteria for the main components of the vehicular fuel cell system, such as traction motor, air compressor and compressor motor, hydrogen storage and delivery, water and heat management, power conditioning, and control and monitoring subsystem are discussed in detail.

  11. Power Limits and Thermodynamics in Fuel Cells

    NASA Astrophysics Data System (ADS)

    Sieniutycz, Stanisław

    2012-10-01

    This paper deals with various energy converters, in particular thermal or chemical engines and fuel cells. Applying a general thermodynamic framework we derive formulae for converters' efficiencies and apply them to estimate power limits in these power systems. We consider power limits for thermal systems propelled by differences of temperatures and chemical or electrochemical systems driven by differences of chemical potentials. We focus on fuel cells which are the electrochemical energy generators. We show that fuel cells satisfy the same modeling principles as thermal machines and apply similar computational schemes.

  12. Stationary power fuel cell commercialization status worldwide

    SciTech Connect

    Williams, M.C.

    1996-12-31

    Fuel cell technologies for stationary power are set to play a role in power generation applications worldwide. The worldwide fuel cell vision is to provide powerplants for the emerging distributed generation and on-site markets. Progress towards commercialization has occurred in all fuel cell development areas. Around 100 ONSI phosphoric acid fuel cell (PAFC) units have been sold, with significant foreign sales in Europe and Japan. Fuji has apparently overcome its PAFC decay problems. Industry-driven molten carbonate fuel cell (MCFC) programs in Japan and the U.S. are conducting megawatt (MW)-class demonstrations, which are bringing the MCFC to the verge of commercialization. Westinghouse Electric, the acknowledged world leader in tubular solid oxide fuel cell (SOFC) technology, continues to set performance records and has completed construction of a 4-MW/year manufacturing facility in the U.S. Fuel cells have also taken a major step forward with the conceptual development of ultra-high efficiency fuel cell/gas turbine plants. Many SOFC developers in Japan, Europe, and North America continue to make significant advances.

  13. DIRECT FUEL CELL/TURBINE POWER PLANT

    SciTech Connect

    Hossein Ghezel-Ayagh

    2004-11-01

    This report includes the progress in development of Direct FuelCell/Turbine{reg_sign} (DFC/T{reg_sign}) power plants for generation of clean power at very high efficiencies. The DFC/T power system is based on an indirectly heated gas turbine to supplement fuel cell generated power. The DFC/T power generation concept extends the high efficiency of the fuel cell by utilizing the fuel cell's byproduct heat in a Brayton cycle. Features of the DFC/T system include: electrical efficiencies of up to 75% on natural gas, 60% on coal gas, minimal emissions, simplicity in design, direct reforming internal to the fuel cell, reduced carbon dioxide release to the environment, and potential cost competitiveness with existing combined cycle power plants. The operation of sub-MW hybrid Direct FuelCell/Turbine power plant test facility with a Capstone C60 microturbine was initiated in March 2003. The inclusion of the C60 microturbine extended the range of operation of the hybrid power plant to higher current densities (higher power) than achieved in previous tests using a 30kW microturbine. The design of multi-MW DFC/T hybrid systems, approaching 75% efficiency on natural gas, was initiated. A new concept was developed based on clusters of One-MW fuel cell modules as the building blocks. System analyses were performed, including systems for near-term deployment and power plants with long-term ultra high efficiency objectives. Preliminary assessment of the fuel cell cluster concept, including power plant layout for a 14MW power plant, was performed.

  14. Direct FuelCell/Turbine Power Plant

    SciTech Connect

    Hossein Ghezel-Ayagh

    2004-11-19

    This report includes the progress in development of Direct Fuel Cell/Turbine. (DFC/T.) power plants for generation of clean power at very high efficiencies. The DFC/T power system is based on an indirectly heated gas turbine to supplement fuel cell generated power. The DFC/T power generation concept extends the high efficiency of the fuel cell by utilizing the fuel cell's byproduct heat in a Brayton cycle. Features of the DFC/T system include: electrical efficiencies of up to 75% on natural gas, 60% on coal gas, minimal emissions, simplicity in design, direct reforming internal to the fuel cell, reduced carbon dioxide release to the environment, and potential cost competitiveness with existing combined cycle power plants. FCE successfully completed testing of the pre-alpha sub-MW DFC/T power plant. This power plant was constructed by integration of a 250kW fuel cell stack and a microturbine. Following these proof-of-concept tests, a stand-alone test of the microturbine verified the turbine power output expectations at an elevated (representative of the packaged unit condition) turbine inlet temperature. Preliminary design of the packaged sub-MW alpha DFC/T unit has been completed and procurement activity has been initiated. The preliminary design of a 40 MW power plant including the key equipment layout and the site plan was completed. A preliminary cost estimate for the 40 MW DFC/T plant has also been prepared. The tests of the cascaded fuel cell concept for achieving high fuel utilizations were completed. The tests demonstrated that the concept results in higher power plant efficiency. Alternate stack flow geometries for increased power output/fuel utilization capabilities are also being evaluated.

  15. High power density carbonate fuel cell

    SciTech Connect

    Yuh, C.; Johnsen, R.; Doyon, J.; Allen, J.

    1996-12-31

    Carbonate fuel cell is a highly efficient and environmentally clean source of power generation. Many organizations worldwide are actively pursuing the development of the technology. Field demonstration of multi-MW size power plant has been initiated in 1996, a step toward commercialization before the turn of the century, Energy Research Corporation (ERC) is planning to introduce a 2.85MW commercial fuel cell power plant with an efficiency of 58%, which is quite attractive for distributed power generation. However, to further expand competitive edge over alternative systems and to achieve wider market penetration, ERC is exploring advanced carbonate fuel cells having significantly higher power densities. A more compact power plant would also stimulate interest in new markets such as ships and submarines where space limitations exist. The activities focused on reducing cell polarization and internal resistance as well as on advanced thin cell components.

  16. The Fuel Cell Powered Club Car Carryall

    NASA Technical Reports Server (NTRS)

    Eichenberg, Dennis J.

    2005-01-01

    The NASA Glenn Research Center initiated development of the Fuel Cell Powered Club Car Carryall as a way to reduce pollution in industrial settings, reduce fossil fuel consumption and reduce operating costs for transportation systems. The Club Car Carryall provides an inexpensive approach to advance the state of the art in electric vehicle technology in a practical application. The project transfers space technology to terrestrial use via non-traditional partners, and provides power system data valuable for future aeronautics and space applications. The work was done under the Hybrid Power Management (HPM) Program. The Carryall is a state of the art, dedicated, electric utility vehicle. Hydrogen powered proton exchange membrane (PEM) fuel cells are the primary power source. Ultracapacitors were used for energy storage as long life, maintenance free operation, and excellent low temperature performance is essential. Metal hydride hydrogen storage was used to store hydrogen in a safe and efficient low-pressure solid form. The report concludes that the Fuel Cell Powered Club Car Carryall can provide excellent performance, and that the implementation of fuel cells in conjunction with ultracapacitors in the power system can provide significant reliability and performance improvements.

  17. DIRECT FUEL CELL/TURBINE POWER PLANT

    SciTech Connect

    Hossein Ghezel-Ayagh

    2003-05-23

    In this reporting period, a milestone was achieved by commencement of testing and operation of the sub-scale hybrid direct fuel cell/turbine (DFC/T{reg_sign}) power plant. The operation was initiated subsequent to the completion of the construction of the balance-of-plant (BOP) and implementation of process and control tests of the BOP for the subscale DFC/T hybrid system. The construction efforts consisted of finishing the power plant insulation and completion of the plant instrumentation including the wiring and tubing required for process measurement and control. The preparation work also included the development of procedures for facility shake down, conditioning and load testing of the fuel cell, integration of the microturbine, and fuel cell/gas turbine load tests. At conclusion of the construction, the process and control (PAC) tests of BOP, including the microturbine, were initiated.

  18. Shuttle orbter fuel cell power plant

    NASA Technical Reports Server (NTRS)

    1983-01-01

    This is one of the three fuel cells that make up the generating system which provides electrical power to the space shuttle orbiter. Each unit measures 14 inches (35 centimeters) high, 15 inches (38 centimeters) wide, 40 inches (101 centimeters) long and weighs 200 pounds.

  19. Monolithic fuel cell based power source for burst power generation

    SciTech Connect

    Fee, D.C.; Blackburn, P.E.; Busch, D.E.; Dees, D.W.; Dusek, J.; Easler, T.E.; Ellingson, W.A.; Flandermeyer, B.K.; Fousek, R.J.; Heiberger, J.J.; Majumdar, S.; McPheeters, C.C.; Mrazek, F.C.; Picciolo, J.J.; Singh, J.P.; Poeppel, R.B.

    1988-01-01

    A unique fuel cell coupled with a low power nuclear reactor presents an attractive approach for SDI burst power requirements. The requisite high power, long-duration bursts appear achievable with appropriate development of the concept. A monolithic fuel cell/nuclear reactor system clearly possesses several advantages. Fabrication methods, performance advantages, and applications are discussed in this report.

  20. Direct FuelCell/Turbine Power Plant

    SciTech Connect

    Hossein Ghezel-Ayagh

    2008-09-30

    This report summarizes the progress made in development of Direct FuelCell/Turbine (DFC/T{reg_sign}) power plants for generation of clean power at very high efficiencies. The DFC/T system employs an indirectly heated Turbine Generator to supplement fuel cell generated power. The concept extends the high efficiency of the fuel cell by utilizing the fuel cell's byproduct heat in a Brayton cycle. Features of the DFC/T system include: electrical efficiencies of up to 75% on natural gas, minimal emissions, reduced carbon dioxide release to the environment, simplicity in design, direct reforming internal to the fuel cell, and potential cost competitiveness with existing combined cycle power plants. Proof-of-concept tests using a sub-MW-class DFC/T power plant at FuelCell Energy's (FCE) Danbury facility were conducted to validate the feasibility of the concept and to measure its potential for electric power production. A 400 kW-class power plant test facility was designed and retrofitted to conduct the tests. The initial series of tests involved integration of a full-size (250 kW) Direct FuelCell stack with a 30 kW Capstone microturbine. The operational aspects of the hybrid system in relation to the integration of the microturbine with the fuel cell, process flow and thermal balances, and control strategies for power cycling of the system, were investigated. A subsequent series of tests included operation of the sub-MW Direct FuelCell/Turbine power plant with a Capstone C60 microturbine. The C60 microturbine extended the range of operation of the hybrid power plant to higher current densities (higher power) than achieved in initial tests using the 30kW microturbine. The proof-of-concept test results confirmed the stability and controllability of operating a fullsize (250 kW) fuel cell stack in combination with a microturbine. Thermal management of the system was confirmed and power plant operation, using the microturbine as the only source of fresh air supply to the

  1. Fuel cell power trains for road traffic

    NASA Astrophysics Data System (ADS)

    Höhlein, Bernd; Biedermann, Peter; Grube, Thomas; Menzer, Reinhard

    Legal regulations, especially the low emission vehicle (LEV) laws in California, are the driving forces for more intensive technological developments with respect to a global automobile market. In the future, high efficient vehicles at very low emission levels will include low temperature fuel cell systems (e.g., polymer electrolyte fuel cell (PEFC)) as units of hydrogen-, methanol- or gasoline-based electric power trains. In the case of methanol or gasoline/diesel, hydrogen has to be produced on-board using heated steam or partial oxidation reformers as well as catalytic burners and gas cleaning units. Methanol could also be used for direct electricity generation inside the fuel cell (direct methanol fuel cell (DMFC)). The development potentials and the results achieved so far for these concepts differ extremely. Based on the experience gained so far, the goals for the next few years include cost and weight reductions as well as optimizations in terms of the energy management of power trains with PEFC systems. At the same time, questions of fuel specification, fuel cycle management, materials balances and environmental assessment will have to be discussed more intensively. On the basis of process engineering analyses for net electricity generation in PEFC-powered power trains as well as on assumptions for both electric power trains and vehicle configurations, overall balances have been carried out. They will lead not only to specific energy demand data and specific emission levels (CO 2, CO, VOC, NO x) for the vehicle but will also present data of its full fuel cycle (FFC) in comparison to those of FFCs including internal combustion engines (ICE) after the year 2005. Depending on the development status (today or in 2010) and the FFC benchmark results, the advantages of balances results of FFC with PEFC vehicles are small in terms of specific energy demand and CO 2 emissions, but very high with respect to local emission levels.

  2. Fuel processor for fuel cell power system

    DOEpatents

    Vanderborgh, Nicholas E.; Springer, Thomas E.; Huff, James R.

    1987-01-01

    A catalytic organic fuel processing apparatus, which can be used in a fuel cell power system, contains within a housing a catalyst chamber, a variable speed fan, and a combustion chamber. Vaporized organic fuel is circulated by the fan past the combustion chamber with which it is in indirect heat exchange relationship. The heated vaporized organic fuel enters a catalyst bed where it is converted into a desired product such as hydrogen needed to power the fuel cell. During periods of high demand, air is injected upstream of the combustion chamber and organic fuel injection means to burn with some of the organic fuel on the outside of the combustion chamber, and thus be in direct heat exchange relation with the organic fuel going into the catalyst bed.

  3. Fuel cell power plants for transportation applications

    SciTech Connect

    Huff, J.R.

    1991-12-31

    Over the past 35 years, the transportation sector has accounted fr approximately 25% of the total gross energy consumption in the United States. As the largest energy user in the United States, transportation accounts for approximately 66% of the country`s current petroleum consumption. Fuel cell power plants using nonpetroleum fuels such as methanol could significantly reduce US dependency on petroleum resources. They offer the additional advantage of minimal air pollution thereby addressing another issue of major concern in the US fuel cell power plant use in city buses and other vehicles is being explored in a number of US Department of Energy and industrial programs that will be described in this paper. 5 refs.

  4. Fuel cell systems for personal and portable power applications

    SciTech Connect

    Fateen, S. A.

    2001-01-01

    Fuel cells are devices that electrochemically convert fuel, usually hydrogen gas, to directly produce electricity. Fuel cells were initially developed for use in the space program to provide electricity and drinking water for astronauts. Fuel cells are under development for use in the automobile industry to power cars and buses with the advantage of lower emissions and higher efficiency than internal combustion engines. Fuel cells also have great potential to be used in portable consumer products like cellular phones and laptop computers, as well as military applications. In fact, any products that use batteries can be powered by fuel cells. In this project, we examine fuel cell system trade-offs between fuel cell type and energy storage/hydrogen production for portable power generation. The types of fuel cells being examined include stored hydrogen PEM (polymer electrolyte), direct methanol fuel cells (DMFC) and indirect methanol fuel cells, where methanol is reformed producing hydrogen. These fuel cells systems can operate at or near ambient conditions, which make them potentially optimal for use in manned personal power applications. The expected power production for these systems is in the range of milliwatts to 500 watts of electrical power for either personal or soldier field use. The fuel cell system trade-offs examine hydrogen storage by metal hydrides, carbon nanotubes, and compressed hydrogen tanks. We examine the weights each system, volume, fuel storage, system costs, system peripherals, power output, and fuel cell feasibility in portable devices.

  5. Fuel cell power plant economic and operational considerations

    NASA Technical Reports Server (NTRS)

    Lance, J. R.

    1984-01-01

    Fuel cell power plants intended for electric utility and cogeneration applications are now in the design and construction stage. This paper describes economic and operational considerations being used in the development and design of plants utilizing air cooled phosphoric acid fuel cells. Fuel cell power plants have some unique characteristics relative to other types of power plants. As a result it was necessary to develop specific definitions of the fuel cell power plant characteristics in order to perform cost of electricity calculations. This paper describes these characteristics and describes the economic analyses used in the Westinghouse fuel cell power plant program.

  6. Solid Oxide Fuel Cell Auxiliary Power Unit

    SciTech Connect

    J. Weber

    2001-12-12

    Solid Oxide Fuel Cell (SOFC) is an attractive, efficient, clean source of power for transportation, military, and stationary applications. Delphi has pioneered its application as an auxiliary Power Unit (APU) for transportation. Delphi is also interested in marketing this technology for stationary applications. Its key advantages are high efficiency and compatibility with gasoline, natural gas and diesel fuel. It's consistent with mechanizations that support the trend to low emissions. Delphi is committed to working with customers and partners to bring this novel technology to market.

  7. DIRECT FUEL CELL/TURBINE POWER PLANT

    SciTech Connect

    Hossein Ghezel-Ayagh

    2003-05-27

    The subMW hybrid DFC/T power plant facility was upgraded with a Capstone C60 microturbine and a state-of-the-art full size fuel cell stack. The integration of the larger microturbine extended the capability of the hybrid power plant to operate at high power ratings with a single gas turbine without the need for supplementary air. The objectives of this phase of subMW hybrid power plant tests are to support the development of process and control and to provide the insight for the design of the packaged subMW hybrid demonstration units. The development of the ultra high efficiency multi-MW power plants was focused on the design of 40 MW power plants with efficiencies approaching 75% (LHV of natural gas). The design efforts included thermodynamic cycle analysis of key gas turbine parameters such as compression ratio.

  8. Fuel Cell Backup Power Geographical Visualization Map (Fact Sheet)

    SciTech Connect

    Not Available

    2012-12-01

    This NREL Hydrogen and Fuel Cell Technical Highlight describes a time-lapse geographical visualization map of early market use of fuel cells for telecommunications backup power. The map synthesizes data being analyzed by NREL's Technology Validation team for the U.S. Department of Energy (DOE) Fuel Cell Technologies Program with DOE's publicly available annual summaries of electric disturbance events.

  9. The role of fuel cells in NASA's space power systems

    NASA Technical Reports Server (NTRS)

    Been, J. F.

    1979-01-01

    A history of the fuel cell technology is presented and compared with NASA's increasing space power requirements. The role of fuel cells is discussed in perspective with other energy storage systems applicable for space using such criteria as type of mission, weight, reliability, costs, etc. Potential applications of space fuel cells with projected technology advances were examined.

  10. Sea water magnesium fuel cell power supply

    NASA Astrophysics Data System (ADS)

    Hahn, Robert; Mainert, Jan; Glaw, Fabian; Lang, K.-D.

    2015-08-01

    An environmentally friendly magnesium fuel cell system using seawater electrolyte and atmospheric oxygen was tested under practical considerations for use as maritime power supply. The hydrogen rate and therefore the power density of the system were increased by a factor of two by using hydrogen evolution cathodes with a gas separation membrane instead of submerged cathodes without gas separation. Commercial magnesium AZ31 rolled sheet anodes can be dissolved in seawater for hydrogen production, down to a thickness below 100 μm thickness, resulting in hydrogen generation efficiency of the anode of over 80%. A practical specific energy/energy density of the alloy of more than 1200 Wh/kg/3000 Wh/l was achieved when coupled to a fuel cell with atmospheric air breathing cathode. The performance of several AZ31 alloy anodes was tested as well as the influence of temperature, electrolyte concentration and anode - cathode separation. The excess hydrogen produced by the magnesium hydrogen evolving cell, due to the negative difference effect, is proportional to the cell current in case of the AZ31 alloys, which simplifies system control considerably. Stable long-term operation of the system was demonstrated at low pressures which can be maintained in an open-seawater-submerged hydrogen generator.

  11. High power density solid oxide fuel cells

    DOEpatents

    Pham, Ai Quoc; Glass, Robert S.

    2004-10-12

    A method for producing ultra-high power density solid oxide fuel cells (SOFCs). The method involves the formation of a multilayer structure cells wherein a buffer layer of doped-ceria is deposited intermediate a zirconia electrolyte and a cobalt iron based electrode using a colloidal spray deposition (CSD) technique. For example, a cobalt iron based cathode composed of (La,Sr)(Co,Fe)O (LSCF) may be deposited on a zirconia electrolyte via a buffer layer of doped-ceria deposited by the CSD technique. The thus formed SOFC have a power density of 1400 mW/cm.sup.2 at 600.degree. C. and 900 mW/cm.sup.2 at 700.degree. C. which constitutes a 2-3 times increased in power density over conventionally produced SOFCs.

  12. DIRECT FUEL CELL/TURBINE POWER PLANT

    SciTech Connect

    Hossein Ghezel-Ayagh

    2003-05-22

    Project activities were focused on the design and construction the sub-scale hybrid Direct Fuel Cell/turbine (DFC/T{reg_sign}) power plant and modification of a Capstone Simple Cycle Model 330 microturbine. The power plant design work included preparation of system flow sheet and performing computer simulations based on conservation of mass and energy. The results of the simulation analyses were utilized to prepare data sheets and specifications for balance-of-plant equipment. Process flow diagram (PFD) and piping and instrumentation diagrams (P&ID) were also completed. The steady state simulation results were used to develop design information for modifying the control functions, and for sizing the heat exchangers required for recuperating the waste heat from the power plant. Line and valve sizes for the interconnecting pipes between the microturbine and the heat recuperators were also identified.

  13. Fuel Cells: Power System Option for Space Research

    NASA Astrophysics Data System (ADS)

    Shaneeth, M.; Mohanty, Surajeet

    2012-07-01

    Fuel Cells are direct energy conversion devices and, thereby, they deliver electrical energy at very high efficiency levels. Hydrogen and Oxygen gases are electrochemically processed, producing clean electric power with water as the only by product. A typical, Fuel Cell based power system involve a Electrochemical power converter, gas storage and management systems, thermal management systems and relevant control units. While there exists different types of Fuel cells, Proton Exchange Membrane (PEM) Fuel Cells are considered as the most suitable one for portable applications. Generally, Fuel Cells are considered as the primary power system option in space missions requiring high power ( > 5kW) and long durations and also where water is a consumable, such as manned missions. This is primarily due to the advantage that fuel cell based power systems offer, in terms of specific energy. Fuel cells have the potential to attain specific energy > 500Wh/kg, specific power >500W/kg, energy density > 400Whr/L and also power density > 200 W/L. This apart, a fuel cell system operate totally independent of sun light, whereas as battery based system is fully dependent on the same. This uniqueness provides added flexibility and capabilities to the missions and modularity for power system. High power requiring missions involving reusable launch vehicles, manned missions etc are expected to be richly benefited from this. Another potential application of Fuel Cell would be interplanetary exploration. Unpredictable and dusty atmospheres of heavenly bodies limits sun light significantly and there fuel cells of different types, eg, Bio-Fuel Cells, PEMFC, DMFCs would be able to work effectively. Manned or unmanned lunar out post would require continuous power even during extra long lunar nights and high power levels are expected. Regenerative Fuel Cells, a combination of Fuel Cells and Electrolysers, are identified as strong candidate. While application of Fuel Cells in high power

  14. Solid oxide fuel cell power system development

    SciTech Connect

    Kerr, Rick; Wall, Mark; Sullivan, Neal

    2015-06-26

    This report summarizes the progress made during this contractual period in achieving the goal of developing the solid oxide fuel cell (SOFC) cell and stack technology to be suitable for use in highly-efficient, economically-competitive, commercially deployed electrical power systems. Progress was made in further understanding cell and stack degradation mechanisms in order to increase stack reliability toward achieving a 4+ year lifetime, in cost reduction developments to meet the SECA stack cost target of $175/kW (in 2007 dollars), and in operating the SOFC technology in a multi-stack system in a real-world environment to understand the requirements for reliably designing and operating a large, stationary power system.

  15. Fuel Cells for Backup Power in Telecommunications Facilities (Fact Sheet)

    SciTech Connect

    Not Available

    2009-04-01

    Telecommunications providers rely on backup power to maintain a constant power supply, to prevent power outages, and to ensure the operability of cell towers, equipment, and networks. The backup power supply that best meets these objectives is fuel cell technology.

  16. Dynamic simulation of a direct carbonate fuel cell power plant

    SciTech Connect

    Ernest, J.B.; Ghezel-Ayagh, H.; Kush, A.K.

    1996-12-31

    Fuel Cell Engineering Corporation (FCE) is commercializing a 2.85 MW Direct carbonate Fuel Cell (DFC) power plant. The commercialization sequence has already progressed through construction and operation of the first commercial-scale DFC power plant on a U.S. electric utility, the 2 MW Santa Clara Demonstration Project (SCDP), and the completion of the early phases of a Commercial Plant design. A 400 kW fuel cell stack Test Facility is being built at Energy Research Corporation (ERC), FCE`s parent company, which will be capable of testing commercial-sized fuel cell stacks in an integrated plant configuration. Fluor Daniel, Inc. provided engineering, procurement, and construction services for SCDP and has jointly developed the Commercial Plant design with FCE, focusing on the balance-of-plant (BOP) equipment outside of the fuel cell modules. This paper provides a brief orientation to the dynamic simulation of a fuel cell power plant and the benefits offered.

  17. Indirect-fired gas turbine dual fuel cell power cycle

    SciTech Connect

    Micheli, P.L.; Williams, M.C.; Sudhoff, F.A.

    1998-04-01

    The present invention relates generally to an integrated fuel cell power plant, and more specifically to a combination of cycles wherein a first fuel cell cycle tops an indirect-fired gas turbine cycle and a second fuel cell cycle bottoms the gas turbine cycle so that the cycles are thermally integrated in a tandem operating arrangement. The United States Government has rights in this invention pursuant to the employer-employee relationship between the United States Department of Energy and the inventors.

  18. Airport electric vehicle powered by fuel cell

    NASA Astrophysics Data System (ADS)

    Fontela, Pablo; Soria, Antonio; Mielgo, Javier; Sierra, José Francisco; de Blas, Juan; Gauchia, Lucia; Martínez, Juan M.

    Nowadays, new technologies and breakthroughs in the field of energy efficiency, alternative fuels and added-value electronics are leading to bigger, more sustainable and green thinking applications. Within the Automotive Industry, there is a clear declaration of commitment with the environment and natural resources. The presence of passenger vehicles of hybrid architecture, public transport powered by cleaner fuels, non-aggressive utility vehicles and an encouraging social awareness, are bringing to light a new scenario where conventional and advanced solutions will be in force. This paper presents the evolution of an airport cargo vehicle from battery-based propulsion to a hybrid power unit based on fuel cell, cutting edge batteries and hydrogen as a fuel. Some years back, IBERIA (Major Airline operating in Spain) decided to initiate the replacement of its diesel fleet for battery ones, aiming at a reduction in terms of contamination and noise in the surrounding environment. Unfortunately, due to extreme operating conditions in airports (ambient temperature, intensive use, dirtiness, …), batteries suffered a very severe degradation, which took its toll in terms of autonomy. This reduction in terms of autonomy together with the long battery recharge time made the intensive use of this fleet impractical in everyday demanding conditions.

  19. AC power generation from microbial fuel cells

    NASA Astrophysics Data System (ADS)

    Lobo, Fernanda Leite; Wang, Heming; Forrestal, Casey; Ren, Zhiyong Jason

    2015-11-01

    Microbial fuel cells (MFCs) directly convert biodegradable substrates to electricity and carry good potential for energy-positive wastewater treatment. However, the low and direct current (DC) output from MFC is not usable for general electronics except small sensors, yet commercial DC-AC converters or inverters used in solar systems cannot be directly applied to MFCs. This study presents a new DC-AC converter system for MFCs that can generate alternating voltage in any desired frequency. Results show that AC power can be easily achieved in three different frequencies tested (1, 10, 60 Hz), and no energy storage layer such as capacitors was needed. The DC-AC converter efficiency was higher than 95% when powered by either individual MFCs or simple MFC stacks. Total harmonic distortion (THD) was used to investigate the quality of the energy, and it showed that the energy could be directly usable for linear electronic loads. This study shows that through electrical conversion MFCs can be potentially used in household electronics for decentralized off-grid communities.

  20. Modeling, analysis and control of fuel cell hybrid power systems

    NASA Astrophysics Data System (ADS)

    Suh, Kyung Won

    Transient performance is a key characteristic of fuel cells, that is sometimes more critical than efficiency, due to the importance of accepting unpredictable electric loads. To fulfill the transient requirement in vehicle propulsion and portable fuel cell applications, a fuel cell stack is typically coupled with a battery through a DC/DC converter to form a hybrid power system. Although many power management strategies already exist, they all rely on low level controllers that realize the power split. In this dissertation we design controllers that realize various power split strategies by directly manipulating physical actuators (low level commands). We maintain the causality of the electric dynamics (voltage and current) and investigate how the electric architecture affects the hybridization level and the power management. We first establish the performance limitations associated with a stand-alone and power-autonomous fuel cell system that is not supplemented by an additional energy storage and powers all its auxiliary components by itself. Specifically, we examine the transient performance in fuel cell power delivery as it is limited by the air supplied by a compressor driven by the fuel cell itself. The performance limitations arise from the intrinsic coupling in the fluid and electrical domain between the compressor and the fuel cell stack. Feedforward and feedback control strategies are used to demonstrate these limitations analytically and with simulations. Experimental tests on a small commercial fuel cell auxiliary power unit (APU) confirm the dynamics and the identified limitations. The dynamics associated with the integration of a fuel cell system and a DC/DC converter is then investigated. Decentralized and fully centralized (using linear quadratic techniques) controllers are designed to regulate the power system voltage and to prevent fuel cell oxygen starvation. Regulating these two performance variables is a difficult task and requires a compromise

  1. Hydrogen fuel cells could power ships at port

    SciTech Connect

    Pratt, Joe

    2013-06-27

    Sandia National Laboratories researcher Joe Pratt conducted a study on the use of hydrogen fuel cells to power docked ships at major ports. He found the potential environmental and cost benefits to be substantial. Here, he discusses the study and explains how hydrogen fuel cells can provide efficient, pollution-free energy to ships at port.

  2. Hydrogen fuel cells could power ships at port

    ScienceCinema

    Pratt, Joe

    2013-11-22

    Sandia National Laboratories researcher Joe Pratt conducted a study on the use of hydrogen fuel cells to power docked ships at major ports. He found the potential environmental and cost benefits to be substantial. Here, he discusses the study and explains how hydrogen fuel cells can provide efficient, pollution-free energy to ships at port.

  3. Regenerative Fuel Cells for Space Power and Energy Conversion (NaBH4/H2O2 Fuel Cell Development)

    NASA Technical Reports Server (NTRS)

    Valdez, Thomas I.; Miley, George H.; Luo, Nie; Burton, Rodney; Mather, Joseph; Hawkins, Glenn; Byrd, Ethan; Gu, Lifeng; Shrestha, Prajakti Joshi

    2006-01-01

    A viewgraph presentation describing hydrogen peroxide and sodium borohydride development is shown. The topics include: 1) Motivation; 2) The Sodium Borohydride Fuel Cell; 3) Fuel Cell Comparisons; 4) MEA Optimization; 5) 500-Watt Stack Testing; 6) System Modeling: Fuel Cell Power Source for Lunar Rovers; and 7) Conclusions

  4. Fuel cell and advanced turbine power cycle

    SciTech Connect

    White, D.J.

    1995-10-19

    Solar Turbines, Incorporated (Solar) has a vested interest in the integration of gas turbines and high temperature fuel cells and in particular, solid oxide fuel cells (SOFCs). Solar has identified a parallel path approach to the technology developments needed for future products. The primary approach is to move away from the simple cycle industrial machines of the past and develop as a first step more efficient recuperated engines. This move was prompted by the recognition that the simple cycle machines were rapidly approaching their efficiency limits. Improving the efficiency of simple cycle machines is and will become increasingly more costly. Each efficiency increment will be progressively more costly than the previous step.

  5. Design and performance of a prototype fuel cell powered vehicle

    SciTech Connect

    Lehman, P.A.; Chamberlin, C.E.

    1996-12-31

    The Schatz Energy Research Center (SERC) is now engaged in the Palm Desert Renewable Hydrogen Transportation System Project. The Project involves a consortium which includes the City of Palm Desert, SERC, the U.S. Department of Energy, the South Coast Air Quality Management District, and Sandia and Lawrence Livermore National Laboratories. Its goal to develop a clean and sustainable transportation system for a community will be accomplished by producing a fleet of fuel cell vehicles, installing a refueling infrastructure utilizing hydrogen generated from solar and wind power, and developing and staffing a fuel cell service and diagnostic center. We will describe details of the project and performance goals for the fuel cell vehicles and associated peripheral systems. In the past year during the first stage in the project, SERC has designed and built a prototype fuel cell powered personal utility vehicle (PUV). These steps included: (1) Designing, building, and testing a 4.0 kW proton exchange membrane (PEM) fuel cell as a power plant for the PUV. (2) Designing, building and testing peripherals including the air delivery, fuel storage/delivery, refueling, water circulation, cooling, and electrical systems. (3) Devising a control algorithm for the fuel cell power plant in the PUV. (4) Designing and building a test bench in which running conditions in the PUV could be simulated and the fuel cell and its peripheral systems tested. (5) Installing an onboard computer and associated electronics into the PUV (6) Assembling and road testing the PUV.

  6. Fuel Cell Based Auxiliary Power Unit for Refrigerated Trucks

    SciTech Connect

    Brooks, Kriston P.

    2014-09-02

    This is the annual report for the Market Transformation project as required by DOE EERE's Fuel Cell Technologies Office. We have been provided with a specific format. It describes the work that was done in developing fuel-cell powered Transport Refrigeration Units for Reefer Trucks. It describes the progress that has been made by Nuvera and Plug Power as they develop and ultimately demonstrate this technology in real world application.

  7. Five Kilowatt Fuel Cell Demonstration for Remote Power Applications

    SciTech Connect

    Dennis Witmer; Tom Johnson; Jack Schmid

    2008-12-31

    While most areas of the US are serviced by inexpensive, dependable grid connected electrical power, many areas of Alaska are not. In these areas, electrical power is provided with Diesel Electric Generators (DEGs), at much higher cost than in grid connected areas. The reasons for the high cost of power are many, including the high relative cost of diesel fuel delivered to the villages, the high operational effort required to maintain DEGs, and the reverse benefits of scale for small utilities. Recent progress in fuel cell technologies have lead to the hope that the DEGs could be replaced with a more efficient, reliable, environmentally friendly source of power in the form of fuel cells. To this end, the University of Alaska Fairbanks has been engaged in testing early fuel cell systems since 1998. Early tests were conducted on PEM fuel cells, but since 2001, the focus has been on Solid Oxide Fuel Cells. In this work, a 5 kW fuel cell was delivered to UAF from Fuel Cell Technologies of Kingston, Ontario. The cell stack is of a tubular design, and was built by Siemens Westinghouse Fuel Cell division. This stack achieved a run of more than 1 year while delivering grid quality electricity from natural gas with virtually no degradation and at an electrical efficiency of nearly 40%. The project was ended after two control system failures resulted in system damage. While this demonstration was successful, considerable additional product development is required before this technology is able to provide electrical energy in remote Alaska. The major issue is cost, and the largest component of system cost currently is the fuel cell stack cost, although the cost of the balance of plant is not insignificant. While several manufactures are working on schemes for significant cost reduction, these systems do not as yet provide the same level of performance and reliability as the larger scale Siemens systems, or levels that would justify commercial deployment.

  8. Power overshoot in two-chambered microbial fuel cell (MFC).

    PubMed

    Nien, Po-Chin; Lee, Chin-Yu; Ho, Kuo-Chuan; Adav, Sunil S; Liu, Lihong; Wang, Aijie; Ren, Nanqi; Lee, Duu-Jong

    2011-04-01

    A two-chamber microbial fuel cell was started using iron-reducing strains as inoculum and acetate as carbon sources. The tested microbial fuel cell had an open-circuit voltage of 0.67 V, and reached 1045 mA m(-2) and a power density of 486 mW m(-2) at 0.46 V before power overshoot occurred. Anodic reactions were identified as the rate-determining steps. Stirring the anolyte insignificantly increased cell performance, suggesting a minimal external mass transfer resistance from the anolyte to the anodic biofilm. Data regression analysis indicates that charge transfer resistance at the biofilm-anode junction was negligible. The order of magnitude estimation of electrical conductance indicates that electron transfer resistance had an insignificant effect on microbial fuel cell performance. Resistance in electrogens for substrate utilization is proposed to induce microbial fuel cell power overshoot. PMID:21295969

  9. Progress and prospects for phosphoric acid fuel cell power plants

    SciTech Connect

    Bonville, L.J.; Scheffler, G.W.; Smith, M.J.

    1996-12-31

    International Fuel Cells (IFC) has developed the fuel cell power plant as a new, on-site power generation source. IFC`s commercial fuel cell product is the 200-kW PC25{trademark} power plant. To date over 100 PC25 units have been manufactured. Fleet operating time is in excess of one million hours. Individual units of the initial power plant model, the PC25 A, have operated for more than 30,000 hours. The first model {open_quotes}C{close_quotes} power plant has over 10,000 hours of operation. The manufacturing, application and operation of this power plant fleet has established a firm base for design and technology development in terms of a clear understanding of the requirements for power plant reliability and durability. This fleet provides the benchmark against which power plant improvements must be measured.

  10. A novel direct ethanol fuel cell with high power density

    NASA Astrophysics Data System (ADS)

    An, L.; Zhao, T. S.; Chen, R.; Wu, Q. X.

    2011-08-01

    A new type of direct ethanol fuel cell (DEFC) that is composed of an alkaline anode and an acid cathode separated with a charger conducting membrane is developed. Theoretically it is shown that the voltage of this novel fuel cell is 2.52 V, while, experimentally it has been demonstrated that this fuel cell can yield an open-circuit voltage (OCV) of 1.60 V and a peak power density of 240 mW cm-2 at 60 °C, which represent the highest performance of DEFCs that has so far been reported in the open literature.

  11. WORKING PARK-FUEL CELL COMBINED HEAT AND POWER SYSTEM

    SciTech Connect

    Allan Jones

    2003-09-01

    This report covers the aims and objectives of the project which was to design, install and operate a fuel cell combined heat and power (CHP) system in Woking Park, the first fuel cell CHP system in the United Kingdom. The report also covers the benefits that were expected to accrue from the work in an understanding of the full technology procurement process (including planning, design, installation, operation and maintenance), the economic and environmental performance in comparison with both conventional UK fuel supply and conventional CHP and the commercial viability of fuel cell CHP energy supply in the new deregulated energy markets.

  12. Heat exchanger for fuel cell power plant reformer

    DOEpatents

    Misage, Robert; Scheffler, Glenn W.; Setzer, Herbert J.; Margiott, Paul R.; Parenti, Jr., Edmund K.

    1988-01-01

    A heat exchanger uses the heat from processed fuel gas from a reformer for a fuel cell to superheat steam, to preheat raw fuel prior to entering the reformer and to heat a water-steam coolant mixture from the fuel cells. The processed fuel gas temperature is thus lowered to a level useful in the fuel cell reaction. The four temperature adjustments are accomplished in a single heat exchanger with only three heat transfer cores. The heat exchanger is preheated by circulating coolant and purge steam from the power section during startup of the latter.

  13. Integrating fuel cell power systems into building physical plants

    SciTech Connect

    Carson, J.

    1996-12-31

    This paper discusses the integration of fuel cell power plants and absorption chillers to cogenerate chilled water or hot water/steam for all weather air conditioning as one possible approach to building system applications. Absorption chillers utilize thermal energy in an absorption based cycle to chill water. It is feasible to use waste heat from fuel cells to provide hydronic heating and cooling. Performance regimes will vary as a function of the supply and quality of waste heat. Respective performance characteristics of fuel cells, absorption chillers and air conditioning systems will define relationships between thermal and electrical load capacities for the combined systems. Specifically, this paper develops thermodynamic relationships between bulk electrical power and cooling/heating capacities for combined fuel cell and absorption chiller system in building applications.

  14. Fuel Cell Combined Heat and Power Commercial Demonstration

    SciTech Connect

    Brooks, Kriston P.; Makhmalbaf, Atefe

    2014-09-02

    This is the annual report for the Market Transformation project as required by DOE EERE's Fuel Cell Technologies Office. We have been provided with a specific format. It describes the work that was done in developing evaluating the performance of 5 kW stationary combined heat and power fuel cell systems that have been deployed in Oregon and California. It also describes the business case that was developed to identify markets and address cost.

  15. Fuel Cells for Portable Power: 1. Introduction to DMFCs; 2. Advanced Materials and Concepts for Portable Power Fuel Cells

    SciTech Connect

    Zelenay, Piotr

    2012-07-16

    Thanks to generally less stringent cost constraints, portable power fuel cells, the direct methanol fuel cell (DMFC) in particular, promise earlier market penetration than higher power polymer electrolyte fuel cells (PEFCs) for the automotive and stationary applications. However, a large-scale commercialization of DMFC-based power systems beyond niche applications already targeted by developers will depend on improvements to fuel cell performance and performance durability as well as on the reduction in cost, especially of the portable systems on the higher end of the power spectrum (100-250 W). In this part of the webinar, we will focus on the development of advanced materials (catalysts, membranes, electrode structures, and membrane electrode assemblies) and fuel cell operating concepts capable of fulfilling two key targets for portable power systems: the system cost of $5/W and overall fuel conversion efficiency of 2.0-2.5 kWh/L. Presented research will concentrate on the development of new methanol oxidation catalysts, hydrocarbon membranes with reduced methanol crossover, and improvements to component durability. Time permitted, we will also present a few highlights from the development of electrocatalysts for the oxidation of two alternative fuels for the direct-feed fuel cells: ethanol and dimethyl ether.

  16. Fuel cell power supply with oxidant and fuel gas switching

    DOEpatents

    McElroy, J.F.; Chludzinski, P.J.; Dantowitz, P.

    1987-04-14

    This invention relates to a fuel cell vehicular power plant. Fuel for the fuel stack is supplied by a hydrocarbon (methanol) catalytic cracking reactor and CO shift reactor. A water electrolysis subsystem is associated with the stack. During low power operation part of the fuel cell power is used to electrolyze water with hydrogen and oxygen electrolysis products being stored in pressure vessels. During peak power intervals, viz, during acceleration or start-up, pure oxygen and pure hydrogen from the pressure vessel are supplied as the reaction gases to the cathodes and anodes in place of air and methanol reformate. This allows the fuel cell stack to be sized for normal low power/air operation but with a peak power capacity several times greater than that for normal operation. 2 figs.

  17. Fuel cell power supply with oxidant and fuel gas switching

    DOEpatents

    McElroy, James F.; Chludzinski, Paul J.; Dantowitz, Philip

    1987-01-01

    This invention relates to a fuel cell vehicular power plant. Fuel for the fuel stack is supplied by a hydrocarbon (methanol) catalytic cracking reactor and CO shift reactor. A water electrolysis subsystem is associated with the stack. During low power operation part of the fuel cell power is used to electrolyze water with hydrogen and oxygen electrolysis products being stored in pressure vessels. During peak power intervals, viz, during acceleration or start-up, pure oxygen and pure hydrogen from the pressure vessel are supplied as the reaction gases to the cathodes and anodes in place of air and methanol reformate. This allows the fuel cell stack to be sized for normal low power/air operation but with a peak power capacity several times greater than that for normal operation.

  18. Neat methanol fuel cell power plant

    NASA Astrophysics Data System (ADS)

    Abens, S.; Farooque, M.

    1985-12-01

    Attention is given to a fuel cell development effort which has been directed, by ease-of-supply, low weight, and low volume criteria toward the use of undiluted methanol. Partial oxidation and internal water recovery concepts are incorporated, allowing the onboard dilution of methanol fuel through mixing with exhaust-recovered water. This scheme is successfully demonstrated for the case of a 3 kW unit employing commercial cross flow heat exchangers, as well as for a 5 kW reformer flue exhaust water recovery design with U.S. Air force baseload stationary applications. The USAF powerplant has an overall thermal efficiency of 32 percent at rated load.

  19. Local biofuels power plants with fuel cell generators

    SciTech Connect

    Lindstroem, O.

    1996-12-31

    The fuel cell should be a most important option for Asian countries now building up their electricity networks. The fuel cell is ideal for the schemes for distributed generation which are more reliable and efficient than the centralized schemes so far favoured by the industrialized countries in the West. Not yet developed small combined cycle power plants with advanced radial gas turbines and compact steam turbines will be the competition. Hot combustion is favoured today but cold combustion may win in the long run thanks to its environmental advantages. Emission standards are in general determined by what is feasible with available technology. The simple conclusion is that the fuel cell has to prove that it is competitive to the turbines in cost engineering terms. A second most important requirement is that the fuel cell option has to be superior with respect to electrical efficiency.

  20. SMALL SCALE FUEL CELL AND REFORMER SYSTEMS FOR REMOTE POWER

    SciTech Connect

    Dennis Witmer

    2003-12-01

    New developments in fuel cell technologies offer the promise of clean, reliable affordable power, resulting in reduced environmental impacts and reduced dependence on foreign oil. These developments are of particular interest to the people of Alaska, where many residents live in remote villages, with no roads or electrical grids and a very high cost of energy, where small residential power systems could replace diesel generators. Fuel cells require hydrogen for efficient electrical production, however. Hydrogen purchased through conventional compressed gas suppliers is very expensive and not a viable option for use in remote villages, so hydrogen production is a critical piece of making fuel cells work in these areas. While some have proposed generating hydrogen from renewable resources such as wind, this does not appear to be an economically viable alternative at this time. Hydrogen can also be produced from hydrocarbon feed stocks, in a process known as reforming. This program is interested in testing and evaluating currently available reformers using transportable fuels: methanol, propane, gasoline, and diesel fuels. Of these, diesel fuels are of most interest, since the existing energy infrastructure of rural Alaska is based primarily on diesel fuels, but this is also the most difficult fuel to reform, due to the propensity for coke formation, due to both the high vaporization temperature and to the high sulfur content in these fuels. There are several competing fuel cell technologies being developed in industry today. Prior work at UAF focused on the use of PEM fuel cells and diesel reformers, with significant barriers identified to their use for power in remote areas, including stack lifetime, system efficiency, and cost. Solid Oxide Fuel Cells have demonstrated better stack lifetime and efficiency in demonstrations elsewhere (though cost still remains an issue), and procuring a system for testing was pursued. The primary function of UAF in the fuel cell

  1. Prospects for advanced coal-fuelled fuel cell power plants

    NASA Astrophysics Data System (ADS)

    Jansen, D.; Vanderlaag, P. C.; Oudhuis, A. B. J.; Ribberink, J. S.

    1994-04-01

    As part of ECN's in-house R&D programs on clean energy conversion systems with high efficiencies and low emissions, system assessment studies have been carried out on coal gasification power plants integrated with high-temperature fuel cells (IGFC). The studies also included the potential to reduce CO2 emissions, and to find possible ways for CO2 extraction and sequestration. The development of this new type of clean coal technology for large-scale power generation is still far off. A significant market share is not envisaged before the year 2015. To assess the future market potential of coal-fueled fuel cell power plants, the promise of this fuel cell technology was assessed against the performance and the development of current state-of-the-art large-scale power generation systems, namely the pulverized coal-fired power plants and the integrated coal gasification combined cycle (IGCC) power plants. With the anticipated progress in gas turbine and gas clean-up technology, coal-fueled fuel cell power plants will have to face severe competition from advanced IGCC power plants, despite their higher efficiency.

  2. The Business Case for Fuel Cells 2012. America's Partner in Power

    SciTech Connect

    Curtin, Sandra; Gangi, Jennifer; Skukowski, Ryan

    2012-12-01

    This report, compiled by Fuel Cells 2000 with support from the Fuel Cell Technologies Program, profiles a select group of nationally recognizable companies and corporations that are deploying or demonstrating fuel cells. These businesses are taking advantage of a fuel cell's unique benefits, especially for powering lift trucks and providing combined heat and power to their stores and administrative offices.

  3. Solid Oxide Fuel Cell Hybrid System for Distributed Power Generation

    SciTech Connect

    Faress Rahman; Nguyen Minh

    2004-01-04

    This report summarizes the work performed by Hybrid Power Generation Systems, LLC (HPGS) during the July 2003 to December 2003 reporting period under Cooperative Agreement DE-FC26-01NT40779 for the U. S. Department of Energy, National Energy Technology Laboratory (DOE/NETL) entitled ''Solid Oxide Fuel Cell Hybrid System for Distributed Power Generation''. The main objective of this project is to develop and demonstrate the feasibility of a highly efficient hybrid system integrating a planar Solid Oxide Fuel Cell (SOFC) and a micro-turbine. In addition, an activity included in this program focuses on the development of an integrated coal gasification fuel cell system concept based on planar SOFC technology. Also, another activity included in this program focuses on the development of SOFC scale up strategies.

  4. Solid Oxide Fuel Cell Hybrid System for Distributed Power Generation

    SciTech Connect

    Nguyen Minh

    2004-07-04

    This report summarizes the work performed by Hybrid Power Generation Systems, LLC (HPGS) during the January to June 2004 reporting period under Cooperative Agreement DE-FC26-01NT40779 for the U. S. Department of Energy, National Energy Technology Laboratory (DOE/NETL) entitled ''Solid Oxide Fuel Cell Hybrid System for Distributed Power Generation''. The main objective of this project is to develop and demonstrate the feasibility of a highly efficient hybrid system integrating a planar Solid Oxide Fuel Cell (SOFC) and a micro-turbine. In addition, an activity included in this program focuses on the development of an integrated coal gasification fuel cell system concept based on planar SOFC technology. Also, another activity included in this program focuses on the development of SOFC scale up strategies.

  5. Methanol reformers for fuel cell powered vehicles: Some design considerations

    SciTech Connect

    Kumar, R.; Ahmed, S.; Krumpelt, M.; Myles, K.M.

    1990-01-01

    Fuel cells are being developed for use in automotive propulsion systems as alternatives for the internal combustion engine in buses, vans, passenger cars. The two most important operational requirements for a stand-alone fuel cell power system for a vehicle are the ability to start up quickly and the ability to supply the necessary power on demand for the dynamically fluctuating load. Methanol is a likely fuel for use in fuel cells for transportation applications. It is a commodity chemical that is manufactured from coal, natural gas, and other feedstocks. For use in a fuel cell, however, the methanol must first be converted (reformed) to a hydrogen-rich gas mixture. The desired features for a methanol reformer include rapid start-up, good dynamic response, high fuel conversion, small size and weight, simple construction and operation, and low cost. In this paper the present the design considerations that are important for developing such a reformer, namely: (1) a small catalyst bed for quick starting, small size, and low weight; (2) multiple catalysts for optimum operation of the dissociation and reforming reactions; (3) reforming by direct heat transfer partial oxidation for rapid response to fluctuating loads; and (4) thermal independence from the rest of the fuel cell system. 10 refs., 1 fig.

  6. High efficiency carbonate fuel cell/turbine hybrid power cycle

    SciTech Connect

    Steinfeld, G.; Maru, H.C.; Sanderson, R.A.

    1996-07-01

    The hybrid power cycle studies were conducted to identify a high efficiency, economically competitive system. A hybrid power cycle which generates power at an LHV efficiency > 70% was identified that includes an atmospheric pressure direct carbonate fuel cell, a gas turbine, and a steam cycle. In this cycle, natural gas fuel is mixed with recycled fuel cell anode exhaust, providing water for reforming fuel. The mixed gas then flows to a direct carbonate fuel cell which generates about 70% of the power. The portion of the anode exhaust which is not recycled is burned and heat transferred through a heat exchanger (HX) to the compressed air from a gas turbine. The heated compressed air is then heated further in the gas turbine burner and expands through the turbine generating 15% of the power. Half the exhaust from the turbine provides air for the anode exhaust burner. All of the turbine exhaust eventually flows through the fuel cell cathodes providing the O2 and CO2 needed in the electrochemical reaction. Exhaust from the cathodes flows to a steam system (heat recovery steam generator, staged steam turbine generating 15% of the cycle power). Simulation of a 200 MW plant with a hybrid power cycle had an LHV efficiency of 72.6%. Power output and efficiency are insensitive to ambient temperature, compared to a gas turbine combined cycle; NOx emissions are 75% lower. Estimated cost of electricity for 200 MW is 46 mills/kWh, which is competitive with combined cycle where fuel cost is > $5.8/MMBTU. Key requirement is HX; in the 200 MW plant studies, a HX operating at 1094 C using high temperature HX technology currently under development by METC for coal gassifiers was assumed. A study of a near term (20 MW) high efficiency direct carbonate fuel cell/turbine hybrid power cycle has also been completed.

  7. Fuel Cell/Turbine Ultra High Efficiency Power System

    SciTech Connect

    Hossein, Ghezel-Ayagh

    2001-11-06

    FuelCell Energy, INC. (FCE) is currently involved in the design of ultra high efficiency power plants under a cooperative agreement (DE-FC26-00NT40) managed by the National Energy Technology Laboratory (NETL) as part of the DOE's Vision 21 program. Under this project, FCE is developing a fuel cell/turbine hybrid system that integrates the atmospheric pressure Direct FuelCell{reg_sign} (DFC{reg_sign}) with an unfired Brayton cycle utilizing indirect heat recovery from the power plant. Features of the DFC/T{trademark} system include: high efficiency, minimal emissions, simplicity in design, direct reforming internal to the fuel cell, no pressurization of the fuel cell, independent operating pressure of the fuel cell and turbine, and potential cost competitiveness with existing combined cycle power plants at much smaller sizes. Objectives of the Vision 21 Program include developing power plants that will generate electricity with net efficiencies approaching 75 percent (with natural gas), while producing sulfur and nitrogen oxide emissions of less than 0.01 lb/million BTU. These goals are significant improvements over conventional power plants, which are 35-60 percent efficient and produce emissions of 0.07 to 0.3 lb/million BTU of sulfur and nitrogen oxides. The nitrogen oxide and sulfur emissions from the DFC/T system are anticipated to be better than the Vision 21 goals due to the non-combustion features of the DFC/T power plant. The expected high efficiency of the DFC/T will also result in a 40-50 percent reduction in carbon dioxide emissions compared to conventional power plants. To date, the R&D efforts have resulted in significant progress including proof-of-concept tests of a sub-scale power plant built around a state-of-the-art DFC stack integrated with a modified Capstone Model 330 Microturbine. The objectives of this effort are to investigate the integration aspects of the fuel cell and turbine and to obtain design information and operational data that will

  8. Solid Oxide Fuel Cell Hybrid System for Distributed Power Generation

    SciTech Connect

    David Deangelis; Rich Depuy; Debashis Dey; Georgia Karvountzi; Nguyen Minh; Max Peter; Faress Rahman; Pavel Sokolov; Deliang Yang

    2004-09-30

    This report summarizes the work performed by Hybrid Power Generation Systems, LLC (HPGS) during the April to October 2004 reporting period in Task 2.3 (SOFC Scaleup for Hybrid and Fuel Cell Systems) under Cooperative Agreement DE-FC26-01NT40779 for the U. S. Department of Energy, National Energy Technology Laboratory (DOE/NETL), entitled ''Solid Oxide Fuel Cell Hybrid System for Distributed Power Generation''. This study analyzes the performance and economics of power generation systems for central power generation application based on Solid Oxide Fuel Cell (SOFC) technology and fueled by natural gas. The main objective of this task is to develop credible scale up strategies for large solid oxide fuel cell-gas turbine systems. System concepts that integrate a SOFC with a gas turbine were developed and analyzed for plant sizes in excess of 20 MW. A 25 MW plant configuration was selected with projected system efficiency of over 65% and a factory cost of under $400/kW. The plant design is modular and can be scaled to both higher and lower plant power ratings. Technology gaps and required engineering development efforts were identified and evaluated.

  9. Fuel economy and range estimates for fuel cell powered automobiles

    SciTech Connect

    Steinbugler, M.; Ogden, J.

    1996-12-31

    While a number of automotive fuel cell applications have been demonstrated, including a golf cart, buses, and a van, these systems and others that have been proposed have utilized differing configurations ranging from direct hydrogen fuel cell-only power plants to fuel cell/battery hybrids operating on reformed methanol. To date there is no clear consensus on which configuration, from among the possible combinations of fuel cell, peaking device, and fuel type, is the most likely to be successfully commercialized. System simplicity favors direct hydrogen fuel cell vehicles, but infrastructure is lacking. Infrastructure favors a system using a liquid fuel with a fuel processor, but system integration and performance issues remain. A number of studies have analyzed particular configurations on either a system or vehicle scale. The objective of this work is to estimate, within a consistent framework, fuel economies and ranges for a variety of configurations using flexible models with the goal of identifying the most promising configurations and the most important areas for further research and development.

  10. FUEL CELL OPERATION ON LANDFILL GAS AT PENROSE POWER STATION

    EPA Science Inventory

    This demonstration test successfully demonstrated operation of a commercial phosphoric acid fuel cell (FC) on landfill gas (LG) at the Penrose Power Station in Sun Valley, CA. Demonstration output included operation up to 137 kW; 37.1% efficiency at 120 kW; exceptionally low sec...

  11. Accelerating Acceptance of Fuel Cell Backup Power Systems - Final Report

    SciTech Connect

    Petrecky, James; Ashley, Christopher

    2014-07-21

    Since 2001, Plug Power has installed more than 800 stationary fuel cell systems worldwide. Plug Power’s prime power systems have produced approximately 6.5 million kilowatt hours of electricity and have accumulated more than 2.5 million operating hours. Intermittent, or backup, power products have been deployed with telecommunications carriers and government and utility customers in North and South America, Europe, the United Kingdom, Japan and South Africa. Some of the largest material handling operations in North America are currently using the company’s motive power units in fuel cell-powered forklifts for their warehouses, distribution centers and manufacturing facilities. The low-temperature GenSys fuel cell system provides remote, off-grid and primary power where grid power is unreliable or nonexistent. Built reliable and designed rugged, low- temperature GenSys delivers continuous or backup power through even the most extreme conditions. Coupled with high-efficiency ratings, low-temperature GenSys reduces operating costs making it an economical solution for prime power requirements. Currently, field trials at telecommunication and industrial sites across the globe are proving the advantages of fuel cells—lower maintenance, fuel costs and emissions, as well as longer life—compared with traditional internal combustion engines.

  12. High efficiency carbonate fuel cell/turbine hybrid power cycles

    SciTech Connect

    Steinfeld, G.

    1995-10-19

    Carbonate fuel cells developed by Energy Research Corporation, in commercial 2.85 MW size, have an efficiency of 57.9 percent. Studies of higher efficiency hybrid power cycles were conducted in cooperation with METC to identify an economically competitive system with an efficiency in excess of 65 percent. A hybrid power cycle was identified that includes a direct carbonate fuel cell, a gas turbine and a steam cycle, which generates power at a LHV efficiency in excess of 70 percent. This new system is called a Tandem Technology Cycle (TTC). In a TTC operating on natural gas fuel, 95 percent of the fuel is mixed with recycled fuel cell anode exhaust, providing water for the reforming of the fuel, and flows to a direct carbonate fuel cell system which generates 72 percent of the power. The portion of the fuel cell anode exhaust which is not recycled, is burned and heat is transferred to the compressed air from a gas turbine, raising its temperature to 1800{degrees}F. The stream is then heated to 2000{degrees}F in the gas turbine burner and expands through the turbine generating 13 percent of the power. Half the exhaust from the gas turbine flows to the anode exhaust burner, and the remainder flows to the fuel cell cathodes providing the O{sub 2} and CO{sub 2} needed in the electrochemical reaction. Exhaust from the fuel cells flows to a steam system which includes a heat recovery steam generator and stages steam turbine which generates 15 percent of the TTC system power. Studies of the TTC for 200-MW and 20-MW size plants quantified performance, emissions and cost-of-electricity, and compared the characteristics of the TTC to gas turbine combined cycles. A 200-MW TTC plant has an efficiency of 72.6 percent, and is relatively insensitive to ambient temperature, but requires a heat exchanger capable of 2000{degrees}F. The estimated cost of electricity is 45.8 mills/kWhr which is not competitive with a combined cycle in installations where fuel cost is under $5.8/MMBtu.

  13. High power density molten carbonate fuel cells

    SciTech Connect

    Bloom, I.; Johnson, S.A.; Geyer, H.K.; Roche, M.F.; Krumpelt, M.; Myles, K.M.

    1995-07-01

    Our results to date indicate that the specific power of the MCFC can be increased from 1200 W/m{sup 2} to above 2000W/m{sup 2} through the use of advanced components such as the double doped LiFeO{sub 2} cathode and pressurized operation. Its volumetric power density can also be increased by an additional 60% by multiple manifolding. Therefore, MCFCs with two to three times the power density of the current generation of MCFCs are possible.

  14. High power density yeast catalyzed microbial fuel cells

    NASA Astrophysics Data System (ADS)

    Ganguli, Rahul

    Microbial fuel cells leverage whole cell biocatalysis to convert the energy stored in energy-rich renewable biomolecules such as sugar, directly to electrical energy at high efficiencies. Advantages of the process include ambient temperature operation, operation in natural streams such as wastewater without the need to clean electrodes, minimal balance-of-plant requirements compared to conventional fuel cells, and environmentally friendly operation. These make the technology very attractive as portable power sources and waste-to-energy converters. The principal problem facing the technology is the low power densities compared to other conventional portable power sources such as batteries and traditional fuel cells. In this work we examined the yeast catalyzed microbial fuel cell and developed methods to increase the power density from such fuel cells. A combination of cyclic voltammetry and optical absorption measurements were used to establish significant adsorption of electron mediators by the microbes. Mediator adsorption was demonstrated to be an important limitation in achieving high power densities in yeast-catalyzed microbial fuel cells. Specifically, the power densities are low for the length of time mediator adsorption continues to occur. Once the mediator adsorption stops, the power densities increase. Rotating disk chronoamperometry was used to extract reaction rate information, and a simple kinetic expression was developed for the current observed in the anodic half-cell. Since the rate expression showed that the current was directly related to microbe concentration close to the electrode, methods to increase cell mass attached to the anode was investigated. Electrically biased electrodes were demonstrated to develop biofilm-like layers of the Baker's yeast with a high concentration of cells directly connected to the electrode. The increased cell mass did increase the power density 2 times compared to a non biofilm fuel cell, but the power density

  15. A portable power system using PEM fuel cells

    SciTech Connect

    Long, E.

    1997-12-31

    Ball has developed a proof-of-concept, small, lightweight, portable power system. The power system uses a proton exchange membrane (PEM) fuel cell stack, stored hydrogen, and atmospheric oxygen as the oxidant to generate electrical power. Electronics monitor the system performance to control cooling air and oxidant flow, and automatically do corrective measures to maintain performance. With the controller monitoring the system health, the system can operate in an ambient environment from 0 C to +50 C. The paper describes system testing, including load testing, thermal and humidity testing, vibration and shock testing, field testing, destructive testing of high-pressure gas tanks, and test results on the fuel cell power system, metal hydride hydrogen storage, high-pressure hydrogen gas storage, and chemical hydride hydrogen storage.

  16. SOLID OXIDE FUEL CELL HYBRID SYSTEM FOR DISTRIBUTED POWER GENERATION

    SciTech Connect

    Faress Rahman; Nguyen Minh

    2003-07-01

    This report summarizes the work performed by Hybrid Power Generation Systems, LLC during the January 2003 to June 2003 reporting period under Cooperative Agreement DE-FC26-01NT40779 for the U. S. Department of Energy, National Energy Technology Laboratory (DOE/NETL) entitled ''Solid Oxide Fuel Cell Hybrid System for Distributed Power Generation''. The main objective of this project is to develop and demonstrate the feasibility of a highly efficient hybrid system integrating a planar Solid Oxide Fuel Cell (SOFC) and a micro-turbine. In addition, an activity included in this program focuses on the development of an integrated coal gasification fuel cell system concept based on planar SOFC technology. This report summarizes the results obtained to date on: System performance analysis and model optimization; Reliability and cost model development; System control including dynamic model development; Heat exchanger material tests and life analysis; Pressurized SOFC evaluation; and Pre-baseline system definition for coal gasification fuel cell system concept.

  17. Solid oxide fuel cell steam reforming power system

    DOEpatents

    Chick, Lawrence A.; Sprenkle, Vincent L.; Powell, Michael R.; Meinhardt, Kerry D.; Whyatt, Greg A.

    2013-03-12

    The present invention is a Solid Oxide Fuel Cell Reforming Power System that utilizes adiabatic reforming of reformate within this system. By utilizing adiabatic reforming of reformate within the system the system operates at a significantly higher efficiency than other Solid Oxide Reforming Power Systems that exist in the prior art. This is because energy is not lost while materials are cooled and reheated, instead the device operates at a higher temperature. This allows efficiencies higher than 65%.

  18. Advanced space power PEM fuel cell systems

    NASA Technical Reports Server (NTRS)

    Vanderborgh, N. E.; Hedstrom, J.; Huff, J. R.

    1989-01-01

    A model showing mass and heat transfer in proton exchange membrane (PEM) single cells is presented. For space applications, stack operation requiring combined water and thermal management is needed. Advanced hardware designs able to combine these two techniques are available. Test results are shown for membrane materials which can operate with sufficiently fast diffusive water transport to sustain current densities of 300 ma per square centimeter. Higher power density levels are predicted to require active water removal.

  19. Fuel-Cell-Powered Vehicle with Hybrid Power Management

    NASA Technical Reports Server (NTRS)

    Eichenberg, Dennis J.

    2010-01-01

    Figure 1 depicts a hybrid electric utility vehicle that is powered by hydrogenburning proton-exchange-membrane (PEM) fuel cells operating in conjunction with a metal hydride hydrogen-storage unit. Unlike conventional hybrid electric vehicles, this vehicle utilizes ultracapacitors, rather than batteries, for storing electric energy. This vehicle is a product of continuing efforts to develop the technological discipline known as hybrid power management (HPM), which is oriented toward integration of diverse electric energy-generating, energy-storing, and energy- consuming devices in optimal configurations. Instances of HPM were reported in five prior NASA Tech Briefs articles, though not explicitly labeled as HPM in the first three articles: "Ultracapacitors Store Energy in a Hybrid Electric Vehicle" (LEW-16876), Vol. 24, No. 4 (April 2000), page 63; "Photovoltaic Power Station With Ultracapacitors for Storage" (LEW- 17177), Vol. 27, No. 8 (August 2003), page 38; "Flasher Powered by Photovoltaic Cells and Ultracapacitors" (LEW-17246), Vol. 27, No. 10 (October 2003), page 37; "Hybrid Power Management" (LEW-17520), Vol. 29, No. 12 (December 2005), page 35; and "Ultracapacitor-Powered Cordless Drill" (LEW-18116-1), Vol. 31, No. 8 (August 2007), page 34. To recapitulate from the cited prior articles: The use of ultracapacitors as energy- storage devices lies at the heart of HPM. An ultracapacitor is an electrochemical energy-storage device, but unlike in a conventional rechargeable electrochemical cell or battery, chemical reactions do not take place during operation. Instead, energy is stored electrostatically at an electrode/electrolyte interface. The capacitance per unit volume of an ultracapacitor is much greater than that of a conventional capacitor because its electrodes have much greater surface area per unit volume and the separation between the electrodes is much smaller.

  20. Fuel cell power source for a cold region

    NASA Astrophysics Data System (ADS)

    Datta, B. K.; Velayutham, G.; Goud, A. Prasad

    Electric power generation at Maitri—the Indian Antarctic station is based on a conventional diesel generator. In spite of the high reliability and simplicity of operation, the main disadvantages of this kind of power source are its pollution potential and fuel transportation costs. In a place like Antarctica environmental protection requirements are of prime importance. Apart from gas pollution, they also suffer from various other problems such as degradation of performance due to sub-zero temperature of operation, noise pollution, solidification of lubricants and mechanical wear and tear. Fuel cells find an ideal application for alternate energy solution, and can maintain the pristine nature of Antarctica. With this objective in mind, Research & Development Establishment (Engineers), Pune, Defence Research & Development Organisation, Ministry of Defence, Government of India joined hands with Centre for Electro-Chemical & Energy Research, SPIC Science Foundation, Chennai and developed three prototype 500 W, 12 V, PEMFC fuel cell power sources for this application. PEMFC has been chosen for study and experimentation at Antarctica because the solid electrolyte Nafion-117 is used in this cell and the electro-chemical reaction is exothermic so that the fuel cell can be activated at low temperature. PEMFC was first installed and successfully demonstrated during the XVII Indian Antarctic Expedition. Further studies continued during the XVIII Indian Antarctic Expedition and a series of scientific experiments were conducted in the areas of optimisation of humidification, temperature for reactants (hydrogen and oxygen), elimination of existing humidification system, feasibility of provision of air-cooling system in lieu of water cooling system, humidifcation of gases using membrane as a medium, charging/discharging characteristics of a metal hydride container for hydrogen storage, and performance of a dc-dc converter and static inverter under sub-zero temperature of

  1. High efficiency fuel cell/advanced turbine power cycles

    SciTech Connect

    Morehead, H.

    1995-10-19

    An outline of the Westinghouse high-efficiency fuel cell/advanced turbine power cycle is presented. The following topics are discussed: The Westinghouse SOFC pilot manufacturing facility, cell scale-up plan, pressure effects on SOFC power and efficiency, sureCell versus conventional gas turbine plants, sureCell product line for distributed power applications, 20 MW pressurized-SOFC/gas turbine power plant, 10 MW SOFC/CT power plant, sureCell plant concept design requirements, and Westinghouse SOFC market entry.

  2. Skid steer fuel cell powered unmanned ground vehicle (Burro)

    NASA Astrophysics Data System (ADS)

    Meldrum, Jay S.; Green, Christopher A.

    2008-04-01

    The use of alternative energy technology for vehicle propulsion and auxiliary power is becoming more important. Work is being performed at Michigan Technological University's Keweenaw Research Center on an Army Research Laboratory cooperative agreement to develop two unmanned ground vehicles for military applications. A wide range of alternative energy technologies were investigated. Hydrogen-powered proton exchange membrane fuel cells were identified as the most appropriate alternative energy source. This is due to some development and commercialization which makes the technology "drop-in plug-in" for immediate use. We have previously presented research work on a small unmanned ground vehicle demonstration platform where the fuel cell is the only power source. We now present research work on the integration of a fuel cell onto a larger skid steer platform. The dual-power capability of this vehicle can provide a modest level of propulsion in "engine-off mode" and may also be used to power directed energy devices which have applications in countermine and similar threat technologies.

  3. Nonlinear observer designs for fuel cell power systems

    NASA Astrophysics Data System (ADS)

    Gorgun, Haluk

    A fuel cell is an electrochemical device that combines hydrogen and oxygen, with the aid of electro-catalysts, to produce electricity. A fuel cell consists of a negatively charged anode, a positively charged cathode and an electrolyte, which transports protons or ions. A low temperature fuel cell has an electrical potential of about 0.7 Volt when generating a current density of 300--500 mA/cm2. Practical fuel cell power systems will require a combination of several cells in series (a stack) to satisfy the voltage requirements of specific applications. Fuel cells are suitable for a potentially wide variety of applications, from stationary power generation in the range of hundreds of megawatts to portable electronics in the range of a couple of watts. Efficient operation of a fuel cell system requires advanced feedback control designs. Reliable measurements from the system are necessary to implement such designs. However, most of the commercially available sensors do not operate properly in the reformate and humidified gas streams in fuel cell systems. Sensors working varying degrees of success are too big and costly, and sensors that are potentially low cost are not reliable or do not have the required life time [28]. Observer designs would eliminate sensor needs for measurements, and make feedback control implementable. Since the fuel cell system dynamics are highly nonlinear, observer design is not an easy task. In this study we aim to develop nonlinear observer design methods applicable to fuel cell systems. In part I of the thesis we design an observer to estimate the hydrogen partial pressure in the anode channel. We treat inlet partial pressure as an unknown slowly varying parameter and develop an adaptive observer that employs a nonlinear voltage injection term. However in this design Fuel Processing System (FPS) dynamics are not modelled, and their effect on the anode dynamics are treated as plant uncertainty. In part II of the thesis we study the FPS

  4. Molten carbonate fuel cell with high power density

    SciTech Connect

    Krumpelt, M.; Roche, M.F.; Bloom, I.; Geyer, H.; Johnson, S.

    1994-08-01

    The objective of this research is a doubling of the current density of the molten carbonate fuel cell (MCFC) from the present value of 1600A/m{sup 2} to 3200 A/m{sup 2} and a similar increase in the volumetric power density. This project is linked to other projects concerning MCFCs (one on the multiply manifolded MCFCs, the other on lithium ferrate and lithium cobaltate cathodes for MCFCs).

  5. A fuel cell-powered battery-charging station

    NASA Astrophysics Data System (ADS)

    Jiang, Zhenhua

    Rechargeable batteries such as lithium-ion cells are playing an increasingly significant role in the utilization of portable electronic devices such as portable computers, cellular phones and camcorders. However, their advantages are partially restricted by the limited usable time. A fuel cell power battery-charging station provides a good solution for recharging these batteries in the fieldwork. This dissertation presents the work on the design, development, validation and implementation of a fuel cell power battery-charging station. The methodology used here is a five-stage research approach: conceptual design, detailed system analysis and design, software validation, hardware validation, and hardware implementation. An effective power processing circuit for the fuel cell powered battery-charging station is designed. Various possible control strategies (including static and real-time control strategies) for active power sharing in the fuel cell powered battery-charging station are discovered in order to minimize the total charging time. A simple method is proposed to estimate the state-of-charge of the battery by estimating the battery open-circuit voltage with current correction and linearly fitting between the open-circuit voltage and the state-of-charge of the battery. These control strategies are then implemented with appropriate approaches in MATLAB/SimulinkRTM. The performances of the various available control strategies are investigated and compared by conducting simulation studies and experiment tests. Experiment data validate the simulation results. Simulation and experiment results also show that the proposed state-of-charge estimation method is effective for the active power sharing strategies. Synergetic control theory is applied to synthesize the controller for buck converters to regulate the pulse current charging of the batteries. This method is completely analytical and uses the full non-linear model of the converter. In comparison to available

  6. Commercial ballard PEM fuel cell natural gas power plant development

    SciTech Connect

    Watkins, D.S.; Dunnison, D.; Cohen, R.

    1996-12-31

    The electric utility industry is in a period of rapid change. Deregulation, wholesale and retail wheeling, and corporate restructuring are forcing utilities to adopt new techniques for conducting their business. The advent of a more customer oriented service business with tailored solutions addressing such needs as power quality is a certain product of the deregulation of the electric utility industry. Distributed and dispersed power are fundamental requirements for such tailored solutions. Because of their modularity, efficiency and environmental benefits, fuel cells are a favored solution to implement distributed and dispersed power concepts. Ballard Power Systems has been working to develop and commercialize Proton Exchange Membrane (PEM) fuel cell power plants for stationary power markets. PEM`s capabilities of flexible operation and multiple market platforms bodes well for success in the stationary power market. Ballard`s stationary commercialization program is now in its second phase. The construction and successful operation of a 10 kW natural gas fueled, proof-of-concept power plant marked the completion of phase one. In the second phase, we are developing a 250 kW market entry power plant. This paper discusses Ballard`s power plant development plan philosophy, the benefits from this approach, and our current status.

  7. Thermally regenerative hydrogen/oxygen fuel cell power cycles

    NASA Technical Reports Server (NTRS)

    Morehouse, J. H.

    1986-01-01

    Two innovative thermodynamic power cycles are analytically examined for future engineering feasibility. The power cycles use a hydrogen-oxygen fuel cell for electrical energy production and use the thermal dissociation of water for regeneration of the hydrogen and oxygen. The TDS (thermal dissociation system) uses a thermal energy input at over 2000 K to thermally dissociate the water. The other cycle, the HTE (high temperature electrolyzer) system, dissociates the water using an electrolyzer operating at high temperature (1300 K) which receives its electrical energy from the fuel cell. The primary advantages of these cycles is that they are basically a no moving parts system, thus having the potential for long life and high reliability, and they have the potential for high thermal efficiency. Both cycles are shown to be classical heat engines with ideal efficiency close to Carnot cycle efficiency. The feasibility of constructing actual cycles is investigated by examining process irreversibilities and device efficiencies for the two types of cycles. The results show that while the processes and devices of the 2000 K TDS exceed current technology limits, the high temperature electrolyzer system appears to be a state-of-the-art technology development. The requirements for very high electrolyzer and fuel cell efficiencies are seen as determining the feasbility of the HTE system, and these high efficiency devices are currently being developed. It is concluded that a proof-of-concept HTE system experiment can and should be conducted.

  8. Advanced coal gasifier-fuel cell power plant systems design

    NASA Technical Reports Server (NTRS)

    Heller, M. E.

    1983-01-01

    Two advanced, high efficiency coal-fired power plants were designed, one utilizing a phosphoric acid fuel cell and one utilizing a molten carbonate fuel cell. Both incorporate a TRW Catalytic Hydrogen Process gasifier and regenerator. Both plants operate without an oxygen plant and without requiring water feed; they, instead, require makeup dolomite. Neither plant requires a shift converter; neither plant has heat exchangers operating above 1250 F. Both plants have attractive efficiencies and costs. While the molten carbonate version has a higher (52%) efficiency than the phosphoric acid version (48%), it also has a higher ($0.078/kWh versus $0.072/kWh) ten-year levelized cost of electricity. The phosphoric acid fuel cell power plant is probably feasible to build in the near term: questions about the TRW process need to be answered experimentally, such as weather it can operate on caking coals, and how effective the catalyzed carbon-dioxide acceptor will be at pilot scale, both in removing carbon dioxide and in removing sulfur from the gasifier.

  9. Solid Oxide Fuel Cell Hybrid System for Distributed Power Generation

    SciTech Connect

    Nguyen Minh

    2002-03-31

    This report summarizes the work performed by Honeywell during the January 2002 to March 2002 reporting period under Cooperative Agreement DE-FC26-01NT40779 for the U. S. Department of Energy, National Energy Technology Laboratory (DOE/NETL) entitled ''Solid Oxide Fuel Cell Hybrid System for Distributed Power Generation''. The main objective of this project is to develop and demonstrate the feasibility of a highly efficient hybrid system integrating a planar Solid Oxide Fuel Cell (SOFC) and a turbogenerator. For this reporting period the following activities have been carried out: {lg_bullet} Conceptual system design trade studies were performed {lg_bullet} System-level performance model was created {lg_bullet} Dynamic control models are being developed {lg_bullet} Mechanical properties of candidate heat exchanger materials were investigated {lg_bullet} SOFC performance mapping as a function of flow rate and pressure was completed

  10. Fuel-Cell Power Source Based on Onboard Rocket Propellants

    NASA Technical Reports Server (NTRS)

    Ganapathi, Gani; Narayan, Sri

    2010-01-01

    The use of onboard rocket propellants (dense liquids at room temperature) in place of conventional cryogenic fuel-cell reactants (hydrogen and oxygen) eliminates the mass penalties associated with cryocooling and boil-off. The high energy content and density of the rocket propellants will also require no additional chemical processing. For a 30-day mission on the Moon that requires a continuous 100 watts of power, the reactant mass and volume would be reduced by 15 and 50 percent, respectively, even without accounting for boiloff losses. The savings increase further with increasing transit times. A high-temperature, solid oxide, electrolyte-based fuel-cell configuration, that can rapidly combine rocket propellants - both monopropellant system with hydrazine and bi-propellant systems such as monomethyl hydrazine/ unsymmetrical dimethyl hydrazine (MMH/UDMH) and nitrogen tetroxide (NTO) to produce electrical energy - overcomes the severe drawbacks of earlier attempts in 1963-1967 of using fuel reforming and aqueous media. The electrical energy available from such a fuel cell operating at 60-percent efficiency is estimated to be 1,500 Wh/kg of reactants. The proposed use of zirconia-based oxide electrolyte at 800-1,000 C will permit continuous operation, very high power densities, and substantially increased efficiency of conversion over any of the earlier attempts. The solid oxide fuel cell is also tolerant to a wide range of environmental temperatures. Such a system is built for easy refueling for exploration missions and for the ability to turn on after several years of transit. Specific examples of future missions are in-situ landers on Europa and Titan that will face extreme radiation and temperature environments, flyby missions to Saturn, and landed missions on the Moon with 14 day/night cycles.

  11. Carbon dioxide separation from high temperature fuel cell power plants

    NASA Astrophysics Data System (ADS)

    Campanari, Stefano

    High temperature fuel cell technologies, solid oxide fuel cells (SOFCs) and molten carbonate fuel cells (MCFCs), are considered for their potential application to carbon dioxide emission control. Both technologies feature electrochemical oxidisation of natural gas reformed fuels, avoiding the mixture of air and fuel flows and dilution with nitrogen and oxygen of the oxidised products; a preliminary analysis shows how the different mechanism of ion transport attributes each technology a specific advantage for the application to CO 2 separation. The paper then compares in the first part the most promising cycle configurations based on high efficiency integrated SOFC/gas turbine "hybrid" cycles, where CO 2 is separated with absorption systems or with the eventual adoption of a second SOFC module acting as an "afterburner". The second part of the paper discusses how a MCFC plant could be "retrofitted" to a conventional fossil-fuel power station, giving the possibility of draining the majority of CO 2 from the stack exhaust while keeping the overall cycle electrical efficiency approximately unchanged.

  12. Thermal management of advanced fuel cell power systems

    NASA Technical Reports Server (NTRS)

    Vanderborgh, N. E.; Hedstrom, J.; Huff, J.

    1990-01-01

    It is shown that fuel cell devices are particularly attractive for the high-efficiency, high-reliability space hardware necessary to support upcoming space missions. These low-temperature hydrogen-oxygen systems necessarily operate with two-phase water. In either PEMFCs (proton exchange membrane fuel cells) or AFCs (alkaline fuel cells), engineering design must be critically focused on both stack temperature control and on the relative humidity control necessary to sustain appropriate conductivity within the ionic conductor. Water must also be removed promptly from the hardware. Present designs for AFC space hardware accomplish thermal management through two coupled cooling loops, both driven by a heat transfer fluid, and involve a recirculation fan to remove water and heat from the stack. There appears to be a certain advantage in using product water for these purposes within PEM hardware, because in that case a single fluid can serve both to control stack temperature, operating simultaneously as a heat transfer medium and through evaporation, and to provide the gas-phase moisture levels necessary to set the ionic conductor at appropriate performance levels. Moreover, the humidification cooling process automatically follows current loads. This design may remove the necessity for recirculation gas fans, thus demonstrating the long-term reliability essential for future space power hardware.

  13. Dynamic behavior of PEM fuel cell and microturbine power plants

    NASA Astrophysics Data System (ADS)

    El-Sharkh, M. Y.; Sisworahardjo, N. S.; Uzunoglu, M.; Onar, O.; Alam, M. S.

    This paper presents a comparison between the dynamic behavior of a 250 kW stand-alone proton exchange membrane fuel cell power plant (PEM FCPP) and a 250 kW stand-alone microturbine (MT). Dynamic models for the two are introduced. To control the voltage and the power output of the PEM FCPP, voltage and power control loops are added to the model. For the MT, voltage, speed, and power control are used. Dynamic models are used to determine the response of the PEM FCPP and MT to a load step change. Simulation results indicate that the response of the MT to reach a steady state is about twice as fast as the PEM FCPP. For stand-alone operation of a PEM FCPP, a set of batteries or ultracapacitors is needed in order to satisfy the power mismatch during transient periods. Software simulation results are obtained by using MATLAB ®, Simulink ®, and SimPowerSystems ®.

  14. Direct fuel cell - A high proficiency power generator for biofuels

    SciTech Connect

    Patel, P.S.; Steinfeld, G.; Baker, B.S.

    1994-12-31

    Conversion of renewable bio-based resources into energy offers significant benefits for our environment and domestic economic activity. It also improves national security by displacing fossil fuels. However, in the current economic environment, it is difficult for biofuel systems to compete with other fossil fuels. The biomass-fired power plants are typically smaller than 50 MW, lower in electrical efficiencies (<25%) and experience greater costs for handling and transporting the biomass. When combined with fuel cells such as the Direct Fuel Cell (DFC), biofuels can produce power more efficiently with negligible environmental impact. Agricultural and other waste biomass can be converted to ethanol or methane-rich biofuels for power generation use in the DFC. These DFC power plants are modular and factory assembled. Due to their electrochemical (non-combustion) conversion process, these plants are environmentally friendly, highly efficient and potentially cost effective, even in sizes as small as a few meagawatts. They can be sited closer to the source of the biomass to minimize handling and transportation costs. The high-grade waste heat available from DFC power plants makes them attractive in cogeneration applications for farming and rural communities. The DFC potentially opens up new markets for biofuels derived from wood, grains and other biomass waste products.

  15. Fuel cells - a new contributor to stationary power

    NASA Astrophysics Data System (ADS)

    Dufour, Angelo U.

    Stationary power generation historically started as distributed generation near the user, with the configuration of a very open market, where a lot of small competing utilities were offering electricity to the customers. At a second time it became a `monopolistic' business because of technical reasons. Big steam turbines and electric generators, allowing better efficiencies, were more conveniently installed in very large power plants, necessarily located in sites far away from where the power was needed, and the transmission losses were bounded by AC high voltage technology. The Governments were, therefore, trying to balance the power of monopolies, that were limiting the economical development of the countries, by strengthening the concept of electrical energy price public control and, alternatively, by establishing rules to allow a free flow of electricity from one region to the other, or taking direct control through ownership of big and small utilities. The most effective way of making the electric energy system competitive has proved to be the opening of a partial competition in the generation field by forcing the utilities to compare the cost of their energy, produced with new centralised plants, to the price of the available energy, coming from combined heat and power dispersed generators. In fact, with reference to this cost, all the peculiar features of large central stations and dispersed generators were taken into account, like the widespread use of natural gas, the investment risk reduction with single smaller increments of capacity, the transmission and distribution siting difficulties and high costs, the improved system reliability, and, finally, the high quality electric power. Fuel Cells are a recently become available technology for distributed electrical energy production, because they share the main typical aspects, relevant for a distributed power system, like compatibility with other modular subsystem packages, fully automation possibility

  16. Direct fuel cell power plants: the final steps to commercialization

    NASA Astrophysics Data System (ADS)

    Glenn, Donald R.

    Since the last paper presented at the Second Grove Fuel Cell Symposium, the Energy Research Corporation (ERC) has established two commercial subsidiaries, become a publically-held firm, expanded its facilities and has moved the direct fuel cell (DFC) technology and systems significantly closer to commercial readiness. The subsidiaries, the Fuel Cell Engineering Corporation (FCE) and Fuel Cell Manufacturing Corporation (FCMC) are perfecting their respective roles in the company's strategy to commercialize its DFC technology. FCE is the prime contractor for the Santa Clara Demonstration and is establishing the needed marketing, sales, engineering, and servicing functions. FCMC in addition to producing the stacks and stack modules for the Santa Clara demonstration plant is now upgrading its production capability and product yields, and retooling for the final stack scale-up for the commercial unit. ERC has built and operated the tallest and largest capacities-to-date carbonate fuel cell stacks as well as numerous short stacks. While most of these units were tested at ERC's Danbury, Connecticut (USA) R&D Center, others have been evaluated at other domestic and overseas facilities using a variety of fuels. ERC has supplied stacks to Elkraft and MTU for tests with natural gas, and RWE in Germany where coal-derived gas were used. Additional stack test activities have been performed by MELCO and Sanyo in Japan. Information from some of these activities is protected by ERC's license arrangements with these firms. However, permission for limited data releases will be requested to provide the Grove Conference with up-to-date results. Arguably the most dramatic demonstration of carbonate fuel cells in the utility-scale, 2 MW power plant demonstration unit, located in the City of Santa Clara, California. Construction of the unit's balance-of-plant (BOP) has been completed and the installed equipment has been operationally checked. Two of the four DFC stack sub-modules, each

  17. The Advantages of Non-Flow-Through Fuel Cell Power Systems for Aerospace Applications

    NASA Technical Reports Server (NTRS)

    Hoberecht, Mark; Burke, Kenneth; Jakupca, Ian

    2011-01-01

    NASA has been developing proton-exchange-membrane (PEM) fuel cell power systems for the past decade, as an upgraded technology to the alkaline fuel cells which presently provide power for the Shuttle Orbiter. All fuel cell power systems consist of one or more fuel cell stacks in combination with appropriate balance-of-plant hardware. Traditional PEM fuel cells are characterized as flow-through, in which recirculating reactant streams remove product water from the fuel cell stack. NASA recently embarked on the development of non-flow-through fuel cell systems, in which reactants are dead-ended into the fuel cell stack and product water is removed by internal wicks. This simplifies the fuel cell power system by eliminating the need for pumps to provide reactant circulation, and mechanical water separators to remove the product water from the recirculating reactant streams. By eliminating these mechanical components, the resulting fuel cell power system has lower mass, volume, and parasitic power requirements, along with higher reliability and longer life. These improved non-flow-through fuel cell power systems therefore offer significant advantages for many aerospace applications.

  18. Fuel Cell Electric Vehicle Powered by Renewable Hydrogen

    SciTech Connect

    2011-01-01

    The National Renewable Energy Laboratory (NREL) recently received a Borrego fuel cell electric vehicle (FCEV) on loan from Kia for display at a variety of summer events. The Borrego is fueled using renewable hydrogen that is produced and dispensed at NREL's National Wind Technology Center near Boulder, Colorado. The hydrogen dispensed at the station is produced via renewable electrolysis as part of the wind-to-hydrogen project, which uses wind turbines and photovoltaic arrays to power electrolyzer stacks that split water into hydrogen and oxygen. The FCEV features state-of-the-art technology with zero harmful emissions.

  19. Fuel Cell Electric Vehicle Powered by Renewable Hydrogen

    ScienceCinema

    None

    2013-05-29

    The National Renewable Energy Laboratory (NREL) recently received a Borrego fuel cell electric vehicle (FCEV) on loan from Kia for display at a variety of summer events. The Borrego is fueled using renewable hydrogen that is produced and dispensed at NREL's National Wind Technology Center near Boulder, Colorado. The hydrogen dispensed at the station is produced via renewable electrolysis as part of the wind-to-hydrogen project, which uses wind turbines and photovoltaic arrays to power electrolyzer stacks that split water into hydrogen and oxygen. The FCEV features state-of-the-art technology with zero harmful emissions.

  20. Experimenting with microbial fuel cells for powering implanted biomedical devices.

    PubMed

    Roxby, Daniel N; Nham Tran; Pak-Lam Yu; Nguyen, Hung T

    2015-08-01

    Microbial Fuel Cell (MFC) technology has the ability to directly convert sugar into electricity by using bacteria. Such a technology could be useful for powering implanted biomedical devices that require a surgery to replace their batteries every couple of years. In steps towards this, parameters such as electrode configuration, inoculation size, stirring of the MFC and single versus dual chamber reactor configuration were tested for their effect on MFC power output. Results indicate that a Top-Bottom electrode configuration, stirring and larger amounts of bacteria in single chamber MFCs, and smaller amounts of bacteria in dual chamber MFCs give increased power outputs. Finally, overall dual chamber MFCs give several fold larger MFC power outputs. PMID:26736845

  1. Air-breathing fuel cell stacks for portable power applications

    SciTech Connect

    Wilson, M.S.; DeCaro, D.; Neutzler, J.K.; Zawodzinski, C.; Gottesfeld, S.

    1996-10-01

    Increasing attention is being directed towards polymer electrolyte fuel cells as battery replacements because of their potentially superior energy densities and the possibility of `mechanical` refueling. On the low end of the power requirement scale (ca. 10 W), fuel cells can compete with primary and secondary batteries only if the fuel cell systems are simple, inexpensive, and reliable. Considerations of cost and simplicity (and minimal parasitic power) discourage the use of conventional performance enhancing subsystems (e.g., humidification, cooling, or forced-reactant flow). We are developing a stack design that is inherently self-regulating to allow effective operation without the benefit of such auxiliary components. The air cathode does not use forced flow to replenish the depleted oxygen. Instead, the oxygen in the air must diffuse into the stack from the periphery of the unit cells. For this reason the stack is described as `air-breathing.` This configuration limits the ability of water to escape which prevents the polymer electrolyte membranes from drying out, even at relatively high continuous operation temperatures (+60 degrees C). This results in stacks with reliable and stable performance. This air-breathing configuration assumes a unique stack geometry that utilizes circular flow-field plates with an annular hydrogen feed manifold and the single tie-bolt extending up through the central axis of the stack. With this geometry, the hydrogen supply to the unit cells is radially outward, and the air supply is from the periphery inward. This configuration has several advantages. The entire periphery is free to air access and allows greater heat conduction to enhance cooling. Furthermore, all of the components in the stack (e.g., the flow-fields, seals and membrane/electrode assemblies), are radially symmetrical, so part fabrication is simple and the entire system is potentially low-cost. Lastly, this configuration is compact and lightweight.

  2. Molten carbonate fuel cell power plant systems studies

    SciTech Connect

    Johnson, W.H.

    1990-06-01

    The goal of the DOE and IFC Molten Carbonate Fuel Cell (MCFC) Program is to develop a MCFC technology base capable of providing clean electrical energy at competitive cost when integrated with coal gasification systems. To be successful, a coal-fueled MCFC system must provide cost of electricity (COE) which is lower than that of current electric generation technologies and which is competitive with other long range electric generating systems. The strategy for the study was to initially evaluate the status of non-fuel cell systems to establish the basis for a competitive CG/MCFC power plant and the corresponding MCFC subsystem goals. Secondly, an iterative and comparative analysis of potential CG/MCFC systems was conducted. This analysis included a detailed examination of MCFC integration with gasifier technology in which the technical basis for MCFC compatibility with a broad range of gasifiers was established. Lastly, a detailed conceptual design was prepared for the most desirable CG/MCFC system. The design established the potential of the CG/MCFC power plant to meet the goals and provide a competitive cost of electricity at very high efficiency and significantly reduced emissions. The design also provided focus for the technical issues still outstanding and required for commercialization of the CG/MCFC technology. 27 figs., 23 tabs.

  3. High power density proton exchange membrane fuel cells

    NASA Technical Reports Server (NTRS)

    Murphy, Oliver J.; Hitchens, G. Duncan; Manko, David J.

    1993-01-01

    Proton exchange membrane (PEM) fuel cells use a perfluorosulfonic acid solid polymer film as an electrolyte which simplifies water and electrolyte management. Their thin electrolyte layers give efficient systems of low weight, and their materials of construction show extremely long laboratory lifetimes. Their high reliability and their suitability for use in a microgravity environment makes them particularly attractive as a substitute for batteries in satellites utilizing high-power, high energy-density electrochemical energy storage systems. In this investigation, the Dow experimental PEM (XUS-13204.10) and unsupported high platinum loading electrodes yielded very high power densities, of the order of 2.5 W cm(exp -2). A platinum black loading of 5 mg per cm(exp 2) was found to be optimum. On extending the three-dimensional reaction zone of fuel cell electrodes by impregnating solid polymer electrolyte into the electrode structures, Nafion was found to give better performance than the Dow experimental PEM. The depth of penetration of the solid polymer electrolyte into electrode structures was 50-70 percent of the thickness of the platinum-catalyzed active layer. However, the degree of platinum utilization was only 16.6 percent and the roughness factor of a typical electrode was 274.

  4. High specific power, direct methanol fuel cell stack

    DOEpatents

    Ramsey, John C.; Wilson, Mahlon S.

    2007-05-08

    The present invention is a fuel cell stack including at least one direct methanol fuel cell. A cathode manifold is used to convey ambient air to each fuel cell, and an anode manifold is used to convey liquid methanol fuel to each fuel cell. Tie-bolt penetrations and tie-bolts are spaced evenly around the perimeter to hold the fuel cell stack together. Each fuel cell uses two graphite-based plates. One plate includes a cathode active area that is defined by serpentine channels connecting the inlet manifold with an integral flow restrictor to the outlet manifold. The other plate includes an anode active area defined by serpentine channels connecting the inlet and outlet of the anode manifold. Located between the two plates is the fuel cell active region.

  5. Intrinsic borohydride fuel cell/battery hybrid power sources

    NASA Astrophysics Data System (ADS)

    Hong, Jian; Fang, Bin; Wang, Chunsheng; Currie, Kenneth

    The electrochemical oxidation behaviors of NaBH 4 on Zn, Zn-MH, and MH (metal-hydride) electrodes were investigated, and an intrinsic direct borohydride fuel cell (DBFC)/battery hybrid power source using MH (or Zn-MH) as the anode and MnO 2 as the cathode was tested. Borohydride cannot be effectively oxidized on Zn electrodes at the Zn oxidation potential because of the poor electrocatalytic ability of Zn for borohydride oxidation and the high overpotential, even though borohydride has the same oxidation potential of Zn in an alkaline solution. The borohydride can be electrochemically oxidized on Ni and MH electrodes through a 4e reaction at a high overpotential. Simply adding borohydride into an alkaline electrolyte of a Zn/air or MH/air battery can greatly increase the capacity, while an intrinsic DBFC/MH(or Zn)-MnO 2 battery can deliver a higher peak power than regular DBFCs.

  6. Power generation properties of Direct Flame Fuel Cell (DFFC)

    NASA Astrophysics Data System (ADS)

    Endo, S.; Nakamura, Y.

    2014-11-01

    This paper investigated the effect of cell temperature and product species concentration induced by small-jet flame on the power generation performance of Direct Flame Fuel Cell (DFFC). The cell is placed above the small flame and heated product gas is impinged toward it and this system is the simplest and smallest unit of the power generation device to be developed. Equivalence ratio (phi) and the distance between the cell and the burner surface (d) are considered as main experimental parameters. It turns out that open circuit voltage (OCV) increases linearly with the increase of temperature in wide range of equivalence ratios. However, it increases drastically at which the equivalence ratio became small (phi <= 2.0) showing inner flame clearly. This result suggests that OCV depends on not only cell temperature but also the species concentration exposed to the cell. It is suggested that Nernst equation might work satisfactory to predict OCV of DFFC.

  7. Hydrogen Fuel Cell Performance as Telecommunications Backup Power in the United States

    SciTech Connect

    Kurtz, Jennifer; Saur, Genevieve; Sprik, Sam

    2015-03-01

    Working in collaboration with the U.S. Department of Energy (DOE) and industry project partners, the National Renewable Energy Laboratory (NREL) acts as the central data repository for the data collected from real-world operation of fuel cell backup power systems. With American Recovery and Reinvestment Act of 2009 (ARRA) co-funding awarded through DOE's Fuel Cell Technologies Office, more than 1,300 fuel cell units were deployed over a three-plus-year period in stationary, material handling equipment, auxiliary power, and backup power applications. This surpassed a Fuel Cell Technologies Office ARRA objective to spur commercialization of an early market technology by installing 1,000 fuel cell units across several different applications, including backup power. By December 2013, 852 backup power units out of 1,330 fuel cell units deployed were providing backup service, mainly for telecommunications towers. For 136 of the fuel cell backup units, project participants provided detailed operational data to the National Fuel Cell Technology Evaluation Center for analysis by NREL's technology validation team. NREL analyzed operational data collected from these government co-funded demonstration projects to characterize key fuel cell backup power performance metrics, including reliability and operation trends, and to highlight the business case for using fuel cells in these early market applications. NREL's analyses include these critical metrics, along with deployment, U.S. grid outage statistics, and infrastructure operation.

  8. Nonlinear Recurrent Neural Network Predictive Control for Energy Distribution of a Fuel Cell Powered Robot

    PubMed Central

    Chen, Qihong; Long, Rong; Quan, Shuhai

    2014-01-01

    This paper presents a neural network predictive control strategy to optimize power distribution for a fuel cell/ultracapacitor hybrid power system of a robot. We model the nonlinear power system by employing time variant auto-regressive moving average with exogenous (ARMAX), and using recurrent neural network to represent the complicated coefficients of the ARMAX model. Because the dynamic of the system is viewed as operating- state- dependent time varying local linear behavior in this frame, a linear constrained model predictive control algorithm is developed to optimize the power splitting between the fuel cell and ultracapacitor. The proposed algorithm significantly simplifies implementation of the controller and can handle multiple constraints, such as limiting substantial fluctuation of fuel cell current. Experiment and simulation results demonstrate that the control strategy can optimally split power between the fuel cell and ultracapacitor, limit the change rate of the fuel cell current, and so as to extend the lifetime of the fuel cell. PMID:24707206

  9. Indirect-fired gas turbine dual fuel cell power cycle

    DOEpatents

    Micheli, Paul L.; Williams, Mark C.; Sudhoff, Frederick A.

    1996-01-01

    A fuel cell and gas turbine combined cycle system which includes dual fuel cell cycles combined with a gas turbine cycle wherein a solid oxide fuel cell cycle operated at a pressure of between 6 to 15 atms tops the turbine cycle and is used to produce CO.sub.2 for a molten carbonate fuel cell cycle which bottoms the turbine and is operated at essentially atmospheric pressure. A high pressure combustor is used to combust the excess fuel from the topping fuel cell cycle to further heat the pressurized gas driving the turbine. A low pressure combustor is used to combust the excess fuel from the bottoming fuel cell to reheat the gas stream passing out of the turbine which is used to preheat the pressurized air stream entering the topping fuel cell before passing into the bottoming fuel cell cathode. The CO.sub.2 generated in the solid oxide fuel cell cycle cascades through the system to the molten carbonate fuel cell cycle cathode.

  10. PRESSURIZED SOLID OXIDE FUEL CELL/GAS TURBINE POWER SYSTEM

    SciTech Connect

    W.L. Lundberg; G.A. Israelson; R.R. Moritz; S.E. Veyo; R.A. Holmes; P.R. Zafred; J.E. King; R.E. Kothmann

    2000-02-01

    Power systems based on the simplest direct integration of a pressurized solid oxide fuel cell (SOFC) generator and a gas turbine (GT) are capable of converting natural gas fuel energy to electric power with efficiencies of approximately 60% (net AC/LHV), and more complex SOFC and gas turbine arrangements can be devised for achieving even higher efficiencies. The results of a project are discussed that focused on the development of a conceptual design for a pressurized SOFC/GT power system that was intended to generate 20 MWe with at least 70% efficiency. The power system operates baseloaded in a distributed-generation application. To achieve high efficiency, the system integrates an intercooled, recuperated, reheated gas turbine with two SOFC generator stages--one operating at high pressure, and generating power, as well as providing all heat needed by the high-pressure turbine, while the second SOFC generator operates at a lower pressure, generates power, and provides all heat for the low-pressure reheat turbine. The system cycle is described, major system components are sized, the system installed-cost is estimated, and the physical arrangement of system components is discussed. Estimates of system power output, efficiency, and emissions at the design point are also presented, and the system cost of electricity estimate is developed.

  11. Fuel-cell based power generating system having power conditioning apparatus

    DOEpatents

    Mazumder, Sudip K.; Pradhan, Sanjaya K.

    2010-10-05

    A power conditioner includes power converters for supplying power to a load, a set of selection switches corresponding to the power converters for selectively connecting the fuel-cell stack to the power converters, and another set of selection switches corresponding to the power converters for selectively connecting the battery to the power converters. The power conveners output combined power that substantially optimally meets a present demand of the load.

  12. Evaluation of the Total Cost of Ownership of Fuel Cell-Powered Material Handling Equipment

    SciTech Connect

    Ramsden, T.

    2013-04-01

    This report discusses an analysis of the total cost of ownership of fuel cell-powered and traditional battery-powered material handling equipment (MHE, or more typically 'forklifts'). A number of fuel cell MHE deployments have received funding support from the federal government. Using data from these government co-funded deployments, DOE's National Renewable Energy Laboratory (NREL) has been evaluating the performance of fuel cells in material handling applications. NREL has assessed the total cost of ownership of fuel cell MHE and compared it to the cost of ownership of traditional battery-powered MHE. As part of its cost of ownership assessment, NREL looked at a range of costs associated with MHE operation, including the capital costs of battery and fuel cell systems, the cost of supporting infrastructure, maintenance costs, warehouse space costs, and labor costs. Considering all these costs, NREL found that fuel cell MHE can have a lower overall cost of ownership than comparable battery-powered MHE.

  13. Overview of commercialization of stationary fuel cell power plants in the United States

    SciTech Connect

    Hooie, D.T.; Williams, M.C.

    1995-07-01

    In this paper, DOE`s efforts to assist private sector organizations to develop and commercialize stationary fuel cell power plants in the United States are discussed. The paper also provides a snapshot of the status of stationary power fuel cell development occurring in the US, addressing all fuel cell types. This paper discusses general characteristics, system configurations, and status of test units and demonstration projects. The US DOE, Morgantown Energy Technology Center is the lead center for implementing DOE`s program for fuel cells for stationary power.

  14. Increased power density from a spiral wound microbial fuel cell.

    PubMed

    Jia, Boyang; Hu, Dawei; Xie, Beizhen; Dong, Kun; Liu, Hong

    2013-03-15

    Using Microbial fuel cell (MFC) to convert organic and inorganic matter into electricity is of great interest for powering portable devices, which is now still limited by the output of MFC. In this study, a spiral wound MFC (SWMFC) with relatively large volume normalized surface area of separator (4.2 cm(2)/ml) was fabricated to enhance power generation. Compared with double-membrane MFC (DMMFC) and conventional double chamber MFC (DCMFC), the power density of SWMFC increased by 42% and 99% resulted from its lower internal resistance. Besides larger separator area, the better performance of SWMFC benefited from its structure sandwiching the cathodes between two separators. This point was proved again by a comparison of another DCMFC and a triple chamber MFC (TCMFC) as well as a simulation using finite element method. Moreover, the feature of SWMFC was more convenient and compact to scale up. Therefore, SWMFC provides a promising configuration for high power output as a portable power source. PMID:23116542

  15. ERC product improvement activities for direct fuel cell power plants

    SciTech Connect

    Maru, H.C.; Farooque, M.; Bentley, C.

    1995-12-01

    This program is designed to advance the carbonate fuel cell technology from the current power plant demonstration status to the commercial design in an approximately five-year period. The specific objectives which will allow attainment of the overall program goal are: (1) Define market-responsive power plant requirements and specifications, (2) Establish the design for a multifuel, low-cost, modular, market-responsive power plant, (3) Resolve power plant manufacturing issues and define the design for the commercial manufacturing facility, (4) Define the stack and BOP equipment packaging arrangement and define module designs, (5) Acquire capability to support developmental testing of stacks and BOP equipment as required to prepare for commercial design, and (6) Resolve stack and BOP equipment technology issues and design, build, and field test a modular commercial prototype power plant to demonstrate readiness for commercial entry. A seven-task program, dedicated to attaining objective(s) in the areas noted above, was initiated in December 1994. Accomplishments of the first six months are discussed in this paper.

  16. ERC product improvement activities for direct fuel cell power plants

    SciTech Connect

    Bentley, C.; Carlson, G.; Doyon, J.

    1995-08-01

    This program is designed to advance the carbonate fuel cell technology from the current power plant demonstration status to the commercial design in an approximately five-year period. The specific objectives which will allow attainment of the overall program goal are: (1) Define market-responsive power plant requirements and specifications, (2) Establish the design for a multifuel, low-cost, modular, market-responsive power plant, (3) Resolve power plant manufacturing issues and define the design for the commercial manufacturing facility, (4) Define the stack and BOP equipment packaging arrangement and define module designs, (5) Acquire capability to support developmental testing of stacks and BOP equipment as required to prepare for commercial design, and (6) Resolve stack and BOP equipment technology issues and design, build, and field test a modular commercial prototype power plant to demonstrate readiness for commercial entry. A seven-task program, dedicated to attaining objective(s) in the areas noted above, was initiated in December 1994. Accomplishments of the first six months are discussed in this paper.

  17. Fuel Cell Power Model Elucidates Life-Cycle Costs for Fuel Cell-Based Combined Heat, Hydrogen, and Power (CHHP) Production Systems (Fact Sheet)

    SciTech Connect

    Not Available

    2010-11-01

    This fact sheet describes NREL's accomplishments in accurately modeling costs for fuel cell-based combined heat, hydrogen, and power systems. Work was performed by NREL's Hydrogen Technologies and Systems Center.

  18. Fuel Cell-Powered Lift Truck Fleet Deployment Projects Final Technical Report May 2014

    SciTech Connect

    Klingler, James J

    2014-05-06

    The overall objectives of this project were to evaluate the performance, operability and safety of fork lift trucks powered by fuel cells in large distribution centers. This was accomplished by replacing the batteries in over 350 lift trucks with fuel cells at five distribution centers operated by GENCO. The annual cost savings of lift trucks powered by fuel cell power units was between $2,400 and $5,300 per truck compared to battery powered lift trucks, excluding DOE contributions. The greatest savings were in fueling labor costs where a fuel cell powered lift truck could be fueled in a few minutes per day compared to over an hour for battery powered lift trucks which required removal and replacement of batteries. Lift truck operators where generally very satisfied with the performance of the fuel cell power units, primarily because there was no reduction in power over the duration of a shift as experienced with battery powered lift trucks. The operators also appreciated the fast and easy fueling compared to the effort and potential risk of injury associated with switching heavy batteries in and out of lift trucks. There were no safety issues with the fueling or operation of the fuel cells. Although maintenance costs for the fuel cells were higher than for batteries, these costs are expected to decrease significantly in the next generation of fuel cells, making them even more cost effective.

  19. Phosphoric acid fuel cell power plant system performance model and computer program

    NASA Technical Reports Server (NTRS)

    Alkasab, K. A.; Lu, C. Y.

    1984-01-01

    A FORTRAN computer program was developed for analyzing the performance of phosphoric acid fuel cell power plant systems. Energy mass and electrochemical analysis in the reformer, the shaft converters, the heat exchangers, and the fuel cell stack were combined to develop a mathematical model for the power plant for both atmospheric and pressurized conditions, and for several commercial fuels.

  20. Challenges for fuel cells as stationary power resource in the evolving energy enterprise

    NASA Astrophysics Data System (ADS)

    Rastler, Dan

    The primary market challenges for fuel cells as stationary power resources in evolving energy markets are reviewed. Fuel cell power systems have significant barriers to overcome in their anticipated role as decentralized energy power systems. Market segments for fuel cells include combined heat and power; low-cost energy, premium power; peak shaving; and load management and grid support. Understanding the role and fit of fuel cell systems in evolving energy markets and the highest value applications are a major challenge for developers and government funding organizations. The most likely adopters of fuel cell systems and the challenges facing each adopter in the target market segment are reviewed. Adopters include generation companies, utility distribution companies, retail energy service providers and end-users. Key challenges include: overcoming technology risk; achieving retail competitiveness; understanding high value markets and end-user needs; distribution and service channels; regulatory policy issues; and the integration of these decentralized resources within the electrical distribution system.

  1. Power management strategy for vehicular-applied hybrid fuel cell/battery power system

    NASA Astrophysics Data System (ADS)

    Li, Xiangjun; Xu, Liangfei; Hua, Jianfeng; Lin, Xinfan; Li, Jianqiu; Ouyang, Minggao

    In this paper, a control strategy for a hybrid PEM (proton exchange membrane) fuel cell/BES (battery energy system) vehicular power system is presented. The strategy, based on fuzzy logic control, incorporates the slow dynamics of fuel cells and the state of charge (SOC) of the BES. Fuel cell output power was determined according to the driving load requirement and the SOC, using fuzzy dynamic decision-making and fuzzy self-organizing concepts. An analysis of the simulation results was conducted using Matlab/Simulink/Stateflow software in order to verify the effectiveness of the proposed control strategy. It was confirmed that the control scheme can be used to improve the operational efficiency of the hybrid power system.

  2. Proton exchange membrane fuel cells for electrical power generation on-board commercial airplanes.

    SciTech Connect

    Curgus, Dita Brigitte; Munoz-Ramos, Karina; Pratt, Joseph William; Akhil, Abbas Ali; Klebanoff, Leonard E.; Schenkman, Benjamin L.

    2011-05-01

    Deployed on a commercial airplane, proton exchange membrane fuel cells may offer emissions reductions, thermal efficiency gains, and enable locating the power near the point of use. This work seeks to understand whether on-board fuel cell systems are technically feasible, and, if so, if they offer a performance advantage for the airplane as a whole. Through hardware analysis and thermodynamic and electrical simulation, we found that while adding a fuel cell system using today's technology for the PEM fuel cell and hydrogen storage is technically feasible, it will not likely give the airplane a performance benefit. However, when we re-did the analysis using DOE-target technology for the PEM fuel cell and hydrogen storage, we found that the fuel cell system would provide a performance benefit to the airplane (i.e., it can save the airplane some fuel), depending on the way it is configured.

  3. Proton Exchange Membrane Fuel Cells for Electrical Power Generation On-Board Commercial Airplanes

    SciTech Connect

    Pratt, Joesph W.; Klebanoff, Leonard E.; Munoz-Ramos, Karina; Akhil, Abbas A.; Curgus, Dita B.; Schenkman, Benjamin L.

    2011-05-01

    Deployed on a commercial airplane, proton exchange membrane fuel cells may offer emissions reductions, thermal efficiency gains, and enable locating the power near the point of use. This work seeks to understand whether on-board fuel cell systems are technically feasible, and, if so, if they offer a performance advantage for the airplane as a whole. Through hardware analysis and thermodynamic and electrical simulation, we found that while adding a fuel cell system using today’s technology for the PEM fuel cell and hydrogen storage is technically feasible, it will not likely give the airplane a performance benefit. However, when we re-did the analysis using DOE-target technology for the PEM fuel cell and hydrogen storage, we found that the fuel cell system would provide a performance benefit to the airplane (i.e., it can save the airplane some fuel), depending on the way it is configured.

  4. Exergy analysis of a fuel cell power system for transportation applications

    SciTech Connect

    Cownden, R.; Nahon, M.; Rosen, M.

    1996-12-31

    An exergy analysis of a solid polymer fuel cell power system for transportation applications is reported. The analysis was completed by implementing the derived fundamental governing second law equations for the system into a fuel cell performance model developed previously. The model analyzes all components of the system including the fuel cell stack and air compression, hydrogen supply, and cooling subsystems. From the analysis, it was determined that the largest destruction of exergy within the system occurs inside the fuel cell stack. Other important sources of exergy destruction include irreversibilities within the hydrogen ejector and the air compressor, and the exergy emission associated with the heat rejected from the radiator. To increase the accuracy of the model and extend the results, a more comprehensive model for the fuel cell stack should be developed, and an investigation should performed into the effects of varying the operating parameters of the system. The results may aid efforts to optimize fuel cell systems.

  5. Power generation from furfural using the microbial fuel cell

    NASA Astrophysics Data System (ADS)

    Luo, Yong; Liu, Guangli; Zhang, Renduo; Zhang, Cuiping

    Furfural is a typical inhibitor in the ethanol fermentation process using lignocellulosic hydrolysates as raw materials. In the literature, no report has shown that furfural can be utilized as the fuel to produce electricity in the microbial fuel cell (MFC), a device that uses microbes to convert organic compounds to generate electricity. In this study, we demonstrated that electricity was successfully generated using furfural as the sole fuel in both the ferricyanide-cathode MFC and the air-cathode MFC. In the ferricyanide-cathode MFC, the maximum power densities reached 45.4, 81.4, and 103 W m -3, respectively, when 1000 mg L -1 glucose, a mixture of 200 mg L -1 glucose and 5 mM furfural, and 6.68 mM furfural were used as the fuels in the anode solution. The corresponding Coulombic efficiencies (CE) were 4.0, 7.1, and 10.2% for the three treatments, respectively. For pure furfural as the fuel, the removal efficiency of furfural reached up to 95% within 12 h. In the air-cathode MFC using 6.68 mM furfural as the fuel, the maximum values of power density and CE were 361 mW m -2 (18 W m -3) and 30.3%, respectively, and the COD removal was about 68% at the end of the experiment (about 30 h). Increase in furfural concentrations from 6.68 to 20 mM resulted in increase in the maximum power densities from 361 to 368 mW m -2, and decrease in CEs from 30.3 to 20.6%. These results indicated that some toxic and biorefractory organics such as furfural might still be suitable resources for electricity generation using the MFC technology.

  6. Novel Sorbent to Clean Biogas for Fuel Cell Combined Heat and Power

    SciTech Connect

    2009-11-01

    TDA Research Inc., in collaboration with FuelCell Energy, will develop a new, high-capacity sorbent to remove sulfur from anaerobic digester gas. This technology will enable the production of a nearly sulfur-free biogas to replace natural gas in fuel cell power plants while reducing greenhouse gas emissions from fossil fuels.

  7. Analysis and Test of a Proton Exchange Membrane Fuel Cell Power System for Space Power Applications

    NASA Technical Reports Server (NTRS)

    Vasquez, Arturo; Varanauski, Donald; Clark, Robert, Jr.

    2000-01-01

    An effort is underway to develop a prototype Proton Exchange Membrane (PEM) Fuel Cell breadboard system for fuhlre space applications. This prototype will be used to develop a comprehensive design basis for a space-rated PEM fuel cell powerplant. The prototype system includes reactant pressure regulators, ejector-based reactant pumps, a 4-kW fuel cell stack and cooling system, and a passive, membranebased oxygen / water separator. A computer model is being developed concurrently to analytically predict fluid flow in the oxidant reactant system. Fuel cells have historically played an important role in human-rated spacecraft. The Gemini and Apollo spacecraft used fuel cells for vehicle electrical power. The Space Shuttle currently uses three Alkaline Fuel Cell Powerplants (AFCP) to generate all of the vehicle's 15-20kW electrical power. Engineers at the Johnson Space Center have leveraged off the development effort ongoing in the commercial arena to develop PEM fuel cel ls for terrestrial uses. The prototype design originated from efforts to develop a PEM fuel cell replacement for the current Space Shuttle AFCP' s. In order to improve on the life and an already excellent hi storical record of reliability and safety, three subsystems were focused on. These were the fuel cell stack itself, the reactant circulation devices, and reactant / product water separator. PEM fuel cell stack performance is already demonstrating the potential for greater than four times the useful life of the current Shuttle's AFCP. Reactant pumping for product water removal has historically been accomplished with mechanical pumps. Ejectors offer an effective means of reactant pumping as well as the potential for weight reduction, control simplification, and long life. Centrifugal water separation is used on the current AFCP. A passive, membrane-based water separator offers compatibility with the micro-gravity environment of space, and the potential for control simplification, elimination of

  8. Direct power generation from waste coffee grounds in a biomass fuel cell

    NASA Astrophysics Data System (ADS)

    Jang, Hansaem; Ocon, Joey D.; Lee, Seunghwa; Lee, Jae Kwang; Lee, Jaeyoung

    2015-11-01

    We demonstrate the possibility of direct power generation from waste coffee grounds (WCG) via high-temperature carbon fuel cell technology. At 900 °C, the WCG-powered fuel cell exhibits a maximum power density that is twice than carbon black. Our results suggest that the heteroatoms and hydrogen contained in WCG are crucial in providing good cell performance due to its in-situ gasification, without any need for pre-reforming. As a first report on the use of coffee as a carbon-neutral fuel, this study shows the potential of waste biomass (e.g. WCG) in sustainable electricity generation in fuel cells.

  9. Self-regulating control of parasitic loads in a fuel cell power system

    NASA Technical Reports Server (NTRS)

    Vasquez, Arturo (Inventor)

    2011-01-01

    A fuel cell power system comprises an internal or self-regulating control of a system or device requiring a parasitic load. The internal or self-regulating control utilizes certain components and an interconnection scheme to produce a desirable, variable voltage potential (i.e., power) to a system or device requiring parasitic load in response to varying operating conditions or requirements of an external load that is connected to a primary fuel cell stack of the system. Other embodiments comprise a method of designing such a self-regulated control scheme and a method of operating such a fuel cell power system.

  10. High power density fuel cell comprising an array of microchannels

    SciTech Connect

    Morse, Jeffrey D.; Upadhye, Ravindra S.; Spadaccini, Christopher M.; Park, Hyung Gyu

    2013-10-15

    A fuel cell according to one embodiment includes a porous electrolyte support structure defining an array of microchannels, the microchannels including fuel and oxidant microchannels; fuel electrodes formed along some of the microchannels; and oxidant electrodes formed along other of the microchannels. A method of making a fuel cell according to one embodiment includes forming an array of walls defining microchannels therebetween using at least one of molding, stamping, extrusion, injection and electrodeposition; processing the walls to make the walls porous, thereby creating a porous electrolyte support structure; forming anode electrodes along some of the microchannels; and forming cathode electrodes along other of the microchannels. Additional embodiments are also disclosed.

  11. An Overview of Power Electronics Applications in Fuel Cell Systems: DC and AC Converters

    PubMed Central

    Ali, M. S.; Kamarudin, S. K.; Masdar, M. S.; Mohamed, A.

    2014-01-01

    Power electronics and fuel cell technologies play an important role in the field of renewable energy. The demand for fuel cells will increase as fuel cells become the main power source for portable applications. In this application, a high-efficiency converter is an essential requirement and a key parameter of the overall system. This is because the size, cost, efficiency, and reliability of the overall system for portable applications primarily depend on the converter. Therefore, the selection of an appropriate converter topology is an important and fundamental aspect of designing a fuel cell system for portable applications as the converter alone plays a major role in determining the overall performance of the system. This paper presents a review of power electronics applications in fuel cell systems, which include various topology combinations of DC converters and AC inverters and which are primarily used in fuel cell systems for portable or stand-alone applications. This paper also reviews the switching techniques used in power conditioning for fuel cell systems. Finally, this paper addresses the current problem encountered with DC converters and AC inverter. PMID:25478581

  12. An overview of power electronics applications in fuel cell systems: DC and AC converters.

    PubMed

    Ali, M S; Kamarudin, S K; Masdar, M S; Mohamed, A

    2014-01-01

    Power electronics and fuel cell technologies play an important role in the field of renewable energy. The demand for fuel cells will increase as fuel cells become the main power source for portable applications. In this application, a high-efficiency converter is an essential requirement and a key parameter of the overall system. This is because the size, cost, efficiency, and reliability of the overall system for portable applications primarily depend on the converter. Therefore, the selection of an appropriate converter topology is an important and fundamental aspect of designing a fuel cell system for portable applications as the converter alone plays a major role in determining the overall performance of the system. This paper presents a review of power electronics applications in fuel cell systems, which include various topology combinations of DC converters and AC inverters and which are primarily used in fuel cell systems for portable or stand-alone applications. This paper also reviews the switching techniques used in power conditioning for fuel cell systems. Finally, this paper addresses the current problem encountered with DC converters and AC inverter. PMID:25478581

  13. An Analytical Performance Assessment of a Fuel Cell-powered, Small Electric Airplane

    NASA Technical Reports Server (NTRS)

    Berton, Jeffrey J.; Freeh, Joshua E.; Wickenheiser, Timothy J.

    2003-01-01

    Rapidly emerging fuel cell power technologies may be used to launch a new revolution of electric propulsion systems for light aircraft. Future small electric airplanes using fuel cell technologies hold the promise of high reliability, low maintenance, low noise, and with exception of water vapor zero emissions. This paper describes an analytical feasibility and performance assessment conducted by NASA's Glenn Research Center of a fuel cell-powered, propeller-driven, small electric airplane based on a model of the MCR 01 two-place kitplane.

  14. ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT: RESIDENTIAL ELECTRIC POWER GENERATION USING THE PLUG POWER SU1 FUEL CELL SYSTEM

    EPA Science Inventory

    The Environmental Technology Verification report discusses the technology and performance of the Plug Power SU1 Fuel Cell System manufactured by Plug Power. The SU1 is a proton exchange membrane fuel cell that requires hydrogen (H2) as fuel. H2 is generally not available, so the ...

  15. Critical assessment of power trains with fuel-cell systems and different fuels

    NASA Astrophysics Data System (ADS)

    Höhlein, B.; von Andrian, S.; Grube, Th; Menzer, R.

    Legal regulations (USA, EU) are a major driving force for intensifying technological developments with respect to the global automobile market. In the future, highly efficient vehicles with very low emission levels will include low-temperature fuel-cell systems (PEFC) as units of electric power trains. With alcohols, ether or hydrocarbons used as fuels for these new electric power trains, hydrogen as PEFC fuel has to be produced on board. These concepts including the direct use of methanol in fuel-cell systems, differ considerably in terms of both their development prospects and the results achieved so far. Based on process engineering analyses for net electricity generation in PEFC-powered power trains, as well as on assumptions for electric power trains and vehicle configurations, different fuel-cell performances and fuel processing units for octane, diesel, methanol, ethanol, propane and dimethylether have been evaluated as fuels. The possible benefits and key challenges for different solutions of power trains with fuel-cell systems/on-board hydrogen production and with direct methanol fuel-cell (DMFC) systems have been assessed. Locally, fuel-cell power trains are almost emission-free and, unlike battery-powered vehicles, their range is comparable to conventional vehicles. Therefore, they have application advantages cases of particularly stringent emission standards requiring zero emission. In comparison to internal combustion engines, using fuel-cell power trains can lead to clear reductions in primary energy demand and global, climate-relevant emissions providing the advantage of the efficiency of the hydrogen/air reaction in the fuel cell is not too drastically reduced by additional conversion steps of on-board hydrogen production, or by losses due to fuel supply provision.

  16. Fuel cell programs in the United States for stationary power applications

    SciTech Connect

    Singer, M.

    1996-04-01

    The Department of Energy (DOE), Office of Fossil Energy, is participating with the private sector in sponsoring the development of molten carbonate fuel cell (MCFC) and solid oxide fuel cell (SOFC) technologies for application in the utility, commercial and industrial sectors. Phosphoric acid fuel cell (PAFC) development was sponsored by the Office of Fossil Energy in previous years and is now being commercialized by the private sector. Private sector participants with the Department of Energy include the Electric Power Research Institute (EPRI), the Gas Research institute (GRI), electric and gas utilities, universities, manufacturing companies and their suppliers. through continued government and private sector support, fuel cell systems are emerging power generation technologies which are expected to have significant worldwide impacts. An industry with annual sales of over a billion dollars is envisioned early in the 21st century. PAFC power plants have begun to enter the marketplace and MCFC and SOFC power plants are expected to be ready to enter the marketplace in the late 1990s. In support of the efficient and effective use of our natural resources, the fuel cell program seeks to increase energy efficiency and economic effectiveness of power generation. This is to be accomplished through effectiveness of power generation. This is accomplished through the development and commercialization of cost-effective, efficient and environmentally desirable fuel cell systems which will operate on fossil fuels in multiple and end use sectors.

  17. A new topology of fuel cell hybrid power source for efficient operation and high reliability

    NASA Astrophysics Data System (ADS)

    Bizon, Nicu

    2011-03-01

    This paper analyzes a new fuel cell Hybrid Power Source (HPS) topology having the feature to mitigate the current ripple of the fuel cell inverter system. In the operation of the inverter system that is grid connected or supplies AC motors in vehicle application, the current ripple normally appears at the DC port of the fuel cell HPS. Consequently, if mitigation measures are not applied, this ripple is back propagated to the fuel cell stack. Other features of the proposed fuel cell HPS are the Maximum Power Point (MPP) tracking, high reliability in operation under sharp power pulses and improved energy efficiency in high power applications. This topology uses an inverter system directly powered from the appropriate fuel cell stack and a controlled buck current source as low power source used for ripple mitigation. The low frequency ripple mitigation is based on active control. The anti-ripple current is injected in HPS output node and this has the LF power spectrum almost the same with the inverter ripple. Consequently, the fuel cell current ripple is mitigated by the designed active control. The ripple mitigation performances are evaluated by indicators that are defined to measure the mitigation ratio of the low frequency harmonics. In this paper it is shown that good performances are obtained by using the hysteretic current control, but better if a dedicated nonlinear controller is used. Two ways to design the nonlinear control law are proposed. First is based on simulation trials that help to draw the characteristic of ripple mitigation ratio vs. fuel cell current ripple. The second is based on Fuzzy Logic Controller (FLC). The ripple factor is up to 1% in both cases.

  18. Micro-tubular flame-assisted fuel cells for micro-combined heat and power systems

    NASA Astrophysics Data System (ADS)

    Milcarek, Ryan J.; Wang, Kang; Falkenstein-Smith, Ryan L.; Ahn, Jeongmin

    2016-02-01

    Currently the role of fuel cells in future power generation is being examined, tested and discussed. However, implementing systems is more difficult because of sealing challenges, slow start-up and complex thermal management and fuel processing. A novel furnace system with a flame-assisted fuel cell is proposed that combines the thermal management and fuel processing systems by utilizing fuel-rich combustion. In addition, the flame-assisted fuel cell furnace is a micro-combined heat and power system, which can produce electricity for homes or businesses, providing resilience during power disruption while still providing heat. A micro-tubular solid oxide fuel cell achieves a significant performance of 430 mW cm-2 operating in a model fuel-rich exhaust stream.

  19. High power density fuel cell comprising an array of microchannels

    SciTech Connect

    Sopchak, David A; Morse, Jeffrey D; Upadhye, Ravindra S; Kotovsky, Jack; Graff, Robert T

    2014-05-06

    A phosphoric acid fuel cell according to one embodiment includes an array of microchannels defined by a porous electrolyte support structure extending between bottom and upper support layers, the microchannels including fuel and oxidant microchannels; fuel electrodes formed along some of the microchannels; and air electrodes formed along other of the microchannels. A method of making a phosphoric acid fuel cell according to one embodiment includes etching an array of microchannels in a substrate, thereby forming walls between the microchannels; processing the walls to make the walls porous, thereby forming a porous electrolyte support structure; forming anode electrodes along some of the walls; forming cathode electrodes along other of the walls; and filling the porous electrolyte support structure with a phosphoric acid electrolyte. Additional embodiments are also disclosed.

  20. Fuel cell power systems for remote applications. Phase 1 final report and business plan

    SciTech Connect

    1998-02-01

    The goal of the Fuel Cell Power Systems for Remote Applications project is to commercialize a 0.1--5 kW integrated fuel cell power system (FCPS). The project targets high value niche markets, including natural gas and oil pipelines, off-grid homes, yachts, telecommunication stations and recreational vehicles. Phase 1 includes the market research, technical and financial analysis of the fuel cell power system, technical and financial requirements to establish manufacturing capability, the business plan, and teaming arrangements. Phase 1 also includes project planning, scope of work, and budgets for Phases 2--4. The project is a cooperative effort of Teledyne Brown Engineering--Energy Systems, Schatz Energy Research Center, Hydrogen Burner Technology, and the City of Palm Desert. Phases 2 through 4 are designed to utilize the results of Phase 1, to further the commercial potential of the fuel cell power system. Phase 2 focuses on research and development of the reformer and fuel cell and is divided into three related, but potentially separate tasks. Budgets and timelines for Phase 2 can be found in section 4 of this report. Phase 2 includes: Task A--Develop a reformate tolerant fuel cell stack and 5 kW reformer; Task B--Assemble and deliver a fuel cell that operates on pure hydrogen to the University of Alaska or another site in Alaska; Task C--Provide support and training to the University of Alaska in the setting up and operating a fuel cell test lab. The Phase 1 research examined the market for power systems for off-grid homes, yachts, telecommunication stations and recreational vehicles. Also included in this report are summaries of the previously conducted market reports that examined power needs for remote locations along natural gas and oil pipelines. A list of highlights from the research can be found in the executive summary of the business plan.

  1. Assessment of the status of fuel cell/battery vehicle power systems

    SciTech Connect

    Escher, W.J.D.; Foster, R.W.

    1980-02-01

    An assessment of the status of the integrated fuel cell/battery power system concept for electric vehicle propulsion is reported. The fuel cell, operating on hydrogen or methanol (indirectly), acts as a very high capacity energy battery for vehicle sustaining operation, while a special power battery provides over-capacity transient power on demand, being recharged by the fuel cell, e.g., during cruising. A focused literature search and a set of industrial and Government contacts were carried out to establish views, outlooks, and general status concerning the concept. It is evident that, although vehicle battery R and D is being actively pursued, little of today's fuel cell work is directed to transportation usage. Only very limited attention has been, and is being, given to the fuel cell/battery power system concept itself. However, judging largely from computer-simulated driving cycle results, the concept can provide needed range capabilities and general operating flexibility to electric vehicles. New transportation applications, conventionally viewed as beyond the capability of electric vehicles, may thereby be practical, e.g., rail, trucks. In view of these potential and important benefits, and the absence of any comprehensive research, development, and demonstration activities which are supportive of the fuel cell/battery system concept, the initiation of an appropriate effort is recommended by the Assessment Team. This general recommendation is supported by applicable findings, observations, and conclusions.

  2. High temperature electrolyzer/fuel cell power cycle: Preliminary design considerations

    NASA Technical Reports Server (NTRS)

    Morehouse, Jeffrey H.

    1987-01-01

    A model of a high temperature electrolyzer/fuel cell, hydrogen/oxygen, thermally regenerative power cycle is developed and used to simulate system performance for varying system parameters. Initial estimates of system efficiency, weight, and volume are provided for a one KWe module assuming specific electrolyzer and fuel cell characteristics, both current and future. Specific interest is placed on examining the system responses to changes in device voltage versus current density operating curves, and the associated optimum operating ranges. The performance of a solar-powered, space based system in low earth orbit is examined in terms of the light-dark periods requiring storage. The storage design tradeoffs between thermal energy, electrical energy, and hydrogen/oxygen mass storage are examined. The current technology module is based on the 1000 C solid oxide electrolyzer cell and the alkaline fuel cell. The Future Technology system examines benefits involved with developing a 1800K electrolyzer operating with an advanced fuel cell.

  3. Interpretation of the power response of a fuel cell with a quadratic logistic differential equation

    SciTech Connect

    Gonzalez, E.R.

    1996-06-01

    The interpretation of the behavior of a fuel cell may be done on the basis of models that require specific assumptions on both the description of the system and the mathematical treatment. This work shows that the power response of a fuel cell can be described by a quadratic logistic differential equation. In this way the interpretation of the dynamical behavior of the system can be done with the general concepts of dissipation, nonlinearity, and feedback.

  4. Fuel Cell/Battery Powered Bus System. Final Report for period August 1987 - December 31, 1997

    SciTech Connect

    Wimmer, R.

    1999-01-01

    Today, fuel cell systems are getting much attention from the automotive industry as a future replacement for the internal combustion engine (ICE). Every US automobile manufacturer and most foreign firms have major programs underway to develop fuel cell engines for transportation. The objective of this program was to investigate the feasibility of using fuel cells as an alternative to the ICE. Three such vehicles (30-foot buses) were introduced beginning in 1994. Extensive development and operational testing of fuel cell systems as a vehicle power source has been accomplished under this program. The development activity investigated total systems configuration and effectiveness for vehicle operations. Operational testing included vehicle performance testing, road operations, and extensive dynamometer emissions testing.

  5. Thermodynamic analysis of Direct Urea Solid Oxide Fuel Cell in combined heat and power applications

    NASA Astrophysics Data System (ADS)

    Abraham, F.; Dincer, I.

    2015-12-01

    This paper presents a comprehensive steady state modelling and thermodynamic analysis of Direct Urea Solid Oxide Fuel Cell integrated with Gas Turbine power cycle (DU-SOFC/GT). The use of urea as direct fuel mitigates public health and safety risks associated with the use of hydrogen and ammonia. The integration scheme in this study covers both oxygen ion-conducting solid oxide fuel cells (SOFC-O) and hydrogen proton-conducting solid oxide fuel cells (SOFC-H). Parametric case studies are carried out to investigate the effects of design and operating parameters on the overall performance of the system. The results reveal that the fuel cell exhibited the highest level of exergy destruction among other system components. Furthermore, the SOFC-O based system offers better overall performance than that with the SOFC-H option mainly due to the detrimental reverse water-gas shift reaction at the SOFC anode as well as the unique configuration of the system.

  6. Dynamic behaviour of Li batteries in hydrogen fuel cell power trains

    NASA Astrophysics Data System (ADS)

    Veneri, O.; Migliardini, F.; Capasso, C.; Corbo, P.

    A Li ion polymer battery pack for road vehicles (48 V, 20 Ah) was tested by charging/discharging tests at different current values, in order to evaluate its performance in comparison with a conventional Pb acid battery pack. The comparative analysis was also performed integrating the two storage systems in a hydrogen fuel cell power train for moped applications. The propulsion system comprised a fuel cell generator based on a 2.5 kW polymeric electrolyte membrane (PEM) stack, fuelled with compressed hydrogen, an electric drive of 1.8 kW as nominal power, of the same typology of that installed on commercial electric scooters (brushless electric machine and controlled bidirectional inverter). The power train was characterized making use of a test bench able to simulate the vehicle behaviour and road characteristics on driving cycles with different acceleration/deceleration rates and lengths. The power flows between fuel cell system, electric energy storage system and electric drive during the different cycles were analyzed, evidencing the effect of high battery currents on the vehicle driving range. The use of Li batteries in the fuel cell power train, adopting a range extender configuration, determined a hydrogen consumption lower than the correspondent Pb battery/fuel cell hybrid vehicle, with a major flexibility in the power management.

  7. Fuel cell-powered microfluidic platform for lab-on-a-chip applications.

    PubMed

    Esquivel, Juan Pablo; Castellarnau, Marc; Senn, Tobias; Löchel, Bernd; Samitier, Josep; Sabaté, Neus

    2012-01-01

    The achievement of a higher degree of integration of components--especially micropumps and power sources--is a challenge currently being pursued to obtain portable and totally autonomous microfluidic devices. This paper presents the integration of a micro direct methanol fuel cell (μDMFC) in a microfluidic platform as a smart solution to provide both electrical and pumping power to a Lab-on-a-Chip system. In this system the electric power produced by the fuel cell is available to enable most of the functionalites required by the microfluidic chip, while the generated CO(2) from the electrochemical reaction produces a pressure capable of pumping a liquid volume through a microchannel. The control of the fuel cell operating conditions allows regulation of the flow rate of a liquid sample through a microfluidic network. The relation between sample flow rate and the current generated by the fuel cell is practically linear, achieving values in the range of 4-18 μL min(-1) while having an available power between 1-4 mW. This permits adjusting the desired flow rate for a given application by controlling the fuel cell output conditions and foresees a fully autonomous analytical Lab-on-a-Chip in which the same device would provide the electrical power to a detection module and at the same time use the CO(2) pumping action to flow the required analytes through a particular microfluidic design. PMID:22072241

  8. Special considerations on operating a fuel cell power plant using natural gas with marginal heating value

    SciTech Connect

    Moses, L. Ng; Chien-Liang Lin; Ya-Tang Cheng

    1996-12-31

    In realizing new power generation technologies in Taiwan, a phosphoric acid fuel cell power plant (model PC2513, ONSI Corporation) has been installed in the premises of the Power Research Institute of the Taiwan Power Company in Taipei County of Taiwan. The pipeline gas supplying to the site of this power plant has a high percentage of carbon dioxide and thus a slightly lower heating value than that specified by the manufacturer. Because of the lowering of heating value of input gas, the highest Output power from the power plant is understandably less than the rated power of 200 kW designed. Further, the transient response of the power plant as interrupted from the Grid is also affected. Since this gas is also the pipeline gas supplying to the heavily populated Taipei Municipal area, it is conceivable that the success of the operations of fuel cells using this fuel is of vital importance to the promotion of the use of this power generation technology in Taiwan. Hence, experiments were set up to assess the feasibility of this fuel cell power plant using the existing pipeline gas in this part of Taiwan where fuel cells would most likely find useful.

  9. Power conversion and quality of the Santa Clara 2 MW direct carbonate fuel cell demonstration plant

    SciTech Connect

    Skok, A.J.; Abueg, R.Z.; Schwartz, P.

    1996-12-31

    The Santa Clara Demonstration Project (SCDP) is the first application of a commercial-scale carbonate fuel cell power plant on a US electric utility system. It is also the largest fuel cell power plant ever operated in the United States. The 2MW plant, located in Santa Clara, California, utilizes carbonate fuel cell technology developed by Energy Research Corporation (ERC) of Danbury, Connecticut. The ultimate goal of a fuel cell power plant is to deliver usable power into an electrical distribution system. The power conversion sub-system does this for the Santa Clara Demonstration Plant. A description of this sub-system and its capabilities follows. The sub-system has demonstrated the capability to deliver real power, reactive power and to absorb reactive power on a utility grid. The sub-system can be operated in the same manner as a conventional rotating generator except with enhanced capabilities for reactive power. Measurements demonstrated the power quality from the plant in various operating modes was high quality utility grade power.

  10. NASA's PEM Fuel Cell Power Plant Development Program for Space Applications

    NASA Technical Reports Server (NTRS)

    Hoberecht, Mark A.

    2008-01-01

    A three-center NASA team led by the Glenn Research Center in Cleveland, Ohio is completing a five-year PEM fuel cell power plant development program for future space applications. The focus of the program has been to adapt commercial PEM fuel cell technology for space applications by addressing the key mission requirements of using pure oxygen as an oxidant and operating in a multi-gravity environment. Competing vendors developed breadboard units in the 1 to 5 kW power range during the first phase of the program, and a single vendor developed a nominal 10-kW engineering model power pant during the second phase of the program. Successful performance and environmental tests conducted by NASA established confidence that PEM fuel cell technology will be ready to meet the electrical power needs of future space missions.

  11. Major design issues of molten carbonate fuel cell power generation unit

    SciTech Connect

    Chen, T.P.

    1996-04-01

    In addition to the stack, a fuel cell power generation unit requires fuel desulfurization and reforming, fuel and oxidant preheating, process heat removal, waste heat recovery, steam generation, oxidant supply, power conditioning, water supply and treatment, purge gas supply, instrument air supply, and system control. These support facilities add considerable cost and system complexity. Bechtel, as a system integrator of M-C Power`s molten carbonate fuel cell development team, has spent substantial effort to simplify and minimize these supporting facilities to meet cost and reliability goals for commercialization. Similiar to other fuels cells, MCFC faces design challenge of how to comply with codes and standards, achieve high efficiency and part load performance, and meanwhile minimize utility requirements, weight, plot area, and cost. However, MCFC has several unique design issues due to its high operating temperature, use of molten electrolyte, and the requirement of CO2 recycle.

  12. Life-cycle cost analysis of conventional and fuel cell/battery powered urban passenger vehicles

    NASA Astrophysics Data System (ADS)

    1992-11-01

    This Final Report summarizes the work on the life cycle cost (LCC) analysis of conventional and fuel cell/battery powered urban passenger vehicles. The purpose of the work is to support the Division in making sound economic comparisons between conventional and fuel cell/battery powered buses, passenger vans, and cars for strategic analysis of programmatic R&D goals. The LCC analysis can indicate whether paying a relatively high initial capital cost for advanced technology with low operating and/or environmental costs is advantageous over paying a lower initial cost for conventional technology with higher operating and/or environmental costs. While minimizing life cycle cost is an important consideration, it does not always result in technology penetration in the marketplace. The LCC analysis model developed under this contract facilitates consideration of all perspectives. Over 100 studies have been acquired and analyzed for their applicability. Drawing on prior work by JPL and Los Alamos National Laboratory as primary sources, specific analytical relationships and cost/performance data relevant to fuel cell/battery and intemal combustion engine (ICE) powered vehicles were selected for development of an LCC analysis model. The completed LCC model is structured around twelve integrated modules. Comparative analysis is made between conventional gasoline and diesel vehicles and fuel cell/battery vehicles using either phosphoric acid fuel cells or proton-exchange membrane fuel cells. In all, seven base vehicle configuration cases with a total of 21 vehicle class/powertrain/fuel combinations are analyzed. The LCC model represents a significant advance in comparative economic analysis of conventional and fuel cell/battery powered vehicle technologies embodying several unique features which were not included in prior models.

  13. Regenerative fuel cell architectures for lunar surface power

    NASA Technical Reports Server (NTRS)

    Harris, D. W.; Gill, S. P.; Nguyen, T. M.; Vrolyk, J. J.

    1991-01-01

    Various Regenerative Fuel Cell (RFC) configurations for the stationary lunar missions were examined using a RFC computer model. For the stationary applications, a GaAs/Ge photovoltaic (PV) array with a 3000 psi gas storage proton exchange membrane (PEM) RFC providing 25 kWe during the day and 12.5 kWe at night was designed. PV/RFC systems utilizing supercritical H2/O2 storage and cryogenic H2/O2 storage for the RFCs were then compared with the baseline high pressure gas storage RFC system. Preliminary results indicate that for long duration nighttime operation missions, the supercritical H2/O2 storage RFC systems offer over 20 percent mass advantage over the high pressure gas storage while the mass savings for the cryogenic H2/O2 storage RFC systems can be as high as 30 percent.

  14. Fuel-Cell-Powered Electric Motor Drive Analyzed for a Large Airplane

    NASA Technical Reports Server (NTRS)

    Brown, Gerald V.; Choi, Benjamin B.

    2005-01-01

    Because of its high efficiency, fuel cell technology may be used to launch a new generation of more-electric aeropropulsion and power systems for future aircraft. Electric-motor-driven airplanes using fuel-cell powerplants would be beneficial to the environment because of fuel savings, low noise, and zero carbon-dioxide emissions. In spite of the fuel cell s efficiency benefit, to produce the same shaft drive power, a fuel cell- powered electric-drive system must be definitely heavier than a turbine-drive system. However, the fuel-cell system s overall efficiency from fuel-to-shaft power is higher than for a turbine-drive system. This means that the fuel consumption rate could be lower than for a conventional system. For heavier, fuel-laden planes for longer flights, we might achieve substantial fuel savings. In the airplane industry, in fact, an efficiency gain of even a few percentage points can make a major economic difference in operating costs.

  15. Generator module architecture for a large solid oxide fuel cell power plant

    DOEpatents

    Gillett, James E.; Zafred, Paolo R.; Riggle, Matthew W.; Litzinger, Kevin P.

    2013-06-11

    A solid oxide fuel cell module contains a plurality of integral bundle assemblies, the module containing a top portion with an inlet fuel plenum and a bottom portion receiving air inlet feed and containing a base support, the base supports dense, ceramic exhaust manifolds which are below and connect to air feed tubes located in a recuperator zone, the air feed tubes passing into the center of inverted, tubular, elongated, hollow electrically connected solid oxide fuel cells having an open end above a combustion zone into which the air feed tubes pass and a closed end near the inlet fuel plenum, where the fuel cells comprise a fuel cell stack bundle all surrounded within an outer module enclosure having top power leads to provide electrical output from the stack bundle, where the fuel cells operate in the fuel cell mode and where the base support and bottom ceramic air exhaust manifolds carry from 85% to all 100% of the weight of the stack, and each bundle assembly has its own control for vertical and horizontal thermal expansion control.

  16. On-board fuel cell power supply modeling on the basis of neural network methodology

    NASA Astrophysics Data System (ADS)

    Jemeı̈, S.; Hissel, D.; Péra, M. C.; Kauffmann, J. M.

    Proton exchange membranes are one of the most promising fuel cell technologies for transportation applications. Considering the aim of transportation applications, a simulation model of the whole fuel cell system is a major milestone. This would lead to the possibility of optimizing the complete vehicle (including all ancillaries, output electrical converter and their dedicated control laws). In a fuel cell system, there is a strong relationship between available electrical power and actual operating conditions: gas conditioning, membrane hydration state, temperature, current set point … Thus, a "minimal behavioral model" of a fuel cell system able to evaluate the output variables and their variations is highly interesting. Artificial neural networks (NN) are a very efficient tool to reach such an aim. In this paper, a proton exchange membrane fuel cell (PEMFC) system neural network model is proposed. It is implemented on Matlab/Simulink ® software and will be integrated to a complete vehicle powertrain. Thus, it will be possible to carry out the development and the simulation of the control laws in order to drive energy transfers on-board fuel cell vehicles.

  17. Hybrid Power Management Program Evaluated Fuel Cell/Ultracapacitor Combinations and Developed Other New Applications

    NASA Technical Reports Server (NTRS)

    Eichenberg, Dennis J.

    2004-01-01

    In fiscal year 2003, the continuation of the Hybrid Power Management (HPM) Program through NASA Glenn Research Center's Commercial Technology Office resulted in several new successful applications of this pioneering technology. HPM is the innovative integration of diverse, state-of-the-art power devices in an optimal configuration for space and terrestrial applications. The appropriate application and control of the various power devices significantly improves overall system performance and efficiency. The advanced power devices include ultracapacitors, fuel cells, and photovoltaics. HPM has extremely wide potential, with applications from nanowatts to megawatts--including power generation, transportation systems, biotechnology systems, and space power systems. HPM has the potential to significantly alleviate global energy concerns, improve the environment, and stimulate the economy. Fuel cells provide excellent efficiency and energy density, but do not have good power density. In contrast, ultracapacitors have excellent power density and virtually unlimited cycle life. To improve the power density of the fuel cell, the combination of fuel cells and ultracapacitors was evaluated.

  18. Performance of a Fuel-Cell-Powered, Small Electric Airplane Assessed

    NASA Technical Reports Server (NTRS)

    Berton, Jeffrey J.

    2004-01-01

    Rapidly emerging fuel-cell-power technologies may be used to launch a new revolution of electric propulsion systems for light aircraft. Future small electric airplanes using fuel cell technologies hold the promise of high reliability, low maintenance, low noise, and - with the exception of water vapor - zero emissions. An analytical feasibility and performance assessment was conducted by NASA Glenn Research Center's Airbreathing Systems Analysis Office of a fuel-cell-powered, propeller-driven, small electric airplane based on a model of the MCR-01 two-place kitplane (Dyn'Aero, Darois, France). This assessment was conducted in parallel with an ongoing effort by the Advanced Technology Products Corporation and the Foundation for Advancing Science and Technology Education. Their project - partially funded by a NASA grant - is to design, build, and fly the first manned, continuously propelled, nongliding electric airplane. In our study, an analytical performance model of a proton exchange membrane (PEM) fuel cell propulsion system was developed and applied to a notional, two-place light airplane modeled after the MCR-01 kitplane. The PEM fuel cell stack was fed pure hydrogen fuel and humidified ambient air via a small automotive centrifugal supercharger. The fuel cell performance models were based on chemical reaction analyses calibrated with published data from the fledgling U.S. automotive fuel cell industry. Electric propeller motors, rated at two shaft power levels in separate assessments, were used to directly drive a two-bladed, variable-pitch propeller. Fuel sources considered were compressed hydrogen gas and cryogenic liquid hydrogen. Both of these fuel sources provided pure, contaminant-free hydrogen for the PEM cells.

  19. A methodology for the validated design space exploration of fuel cell powered unmanned aerial vehicles

    NASA Astrophysics Data System (ADS)

    Moffitt, Blake Almy

    Unmanned Aerial Vehicles (UAVs) are the most dynamic growth sector of the aerospace industry today. The need to provide persistent intelligence, surveillance, and reconnaissance for military operations is driving the planned acquisition of over 5,000 UAVs over the next five years. The most pressing need is for quiet, small UAVs with endurance beyond what is capable with advanced batteries or small internal combustion propulsion systems. Fuel cell systems demonstrate high efficiency, high specific energy, low noise, low temperature operation, modularity, and rapid refuelability making them a promising enabler of the small, quiet, and persistent UAVs that military planners are seeking. Despite the perceived benefits, the actual near-term performance of fuel cell powered UAVs is unknown. Until the auto industry began spending billions of dollars in research, fuel cell systems were too heavy for useful flight applications. However, the last decade has seen rapid development with fuel cell gravimetric and volumetric power density nearly doubling every 2--3 years. As a result, a few design studies and demonstrator aircraft have appeared, but overall the design methodology and vehicles are still in their infancy. The design of fuel cell aircraft poses many challenges. Fuel cells differ fundamentally from combustion based propulsion in how they generate power and interact with other aircraft subsystems. As a result, traditional multidisciplinary analysis (MDA) codes are inappropriate. Building new MDAs is difficult since fuel cells are rapidly changing in design, and various competitive architectures exist for balance of plant, hydrogen storage, and all electric aircraft subsystems. In addition, fuel cell design and performance data is closely protected which makes validation difficult and uncertainty significant. Finally, low specific power and high volumes compared to traditional combustion based propulsion result in more highly constrained design spaces that are

  20. A MEMS-based reformed methanol fuel cell for portable power

    NASA Astrophysics Data System (ADS)

    Morse, J. D.; Upadhye, R. S.; Graff, R. T.; Spadaccini, C.; Park, H. G.; Hart, E. K.

    2007-09-01

    A reformed methanol fuel cell system is described. The use of a microfluidic fuel processor enables component scaling and integration sufficient to achieve power sources in the 2 10 W regime that are competitive in size and energy density in comparison to alternative power sources. While carbon monoxide tolerance of proton conducting membranes has typically limited the performance of reformed methanol fuel cells, phosphoric-acid-doped polybenzimidazole (PBI) membranes have been tested that exhibit no degradation for carbon monoxide >2% mole fraction. Further benefits of the PBI membrane include operating temperature of 150 200 °C, and no need for water to assist protonic conduction. As a result, a chemically and thermally robust fuel cell power source is realized. Results of methanol steam reforming and catalytic combustor heating elements formed in a silicon MEMS platform, and PBI membrane performance with reformate fuel feed will be discussed.

  1. Testing and Evaluation of Batteries for a Fuel Cell Powered Hybrid Bus

    SciTech Connect

    Miller, J.F.; Webster, C.E.; Tummillo, A.F.; DeLuca, W.H.

    1997-05-01

    Argonne National Laboratory conducted performance characterization and life-cycle tests on various batteries to qualify them for use in a fuel cell/battery hybrid bus. On this bus, methanol-fueled, phosphoric acid fuel cells provide routine power needs, while batteries are used to store energy recovered during bus braking and to produce short-duration power during acceleration. Argonne carried out evaluation and endurance testing on several lead-acid and nickel/cadmium batteries selected by the bus developer as potential candidates for the bus application. Argonne conducted over 10,000 hours of testing, simulating more than 80,000 miles of fuel cell bus operation, for the nickel/cadmium battery, which was ultimately selected for use in the three hybrid buses built under the direction of H-Power Corp.

  2. ISRU Reactant, Fuel Cell Based Power Plant for Robotic and Human Mobile Exploration Applications

    NASA Technical Reports Server (NTRS)

    Baird, Russell S.; Sanders, Gerald; Simon, Thomas; McCurdy, Kerri

    2003-01-01

    Three basic power generation system concepts are generally considered for lander, rover, and Extra-Vehicular Activity (EVA) assistant applications for robotic and human Moon and Mars exploration missions. The most common power system considered is the solar array and battery system. While relatively simple and successful, solar array/battery systems have some serious limitations for mobile applications. For typical rover applications, these limitations include relatively low total energy storage capabilities, daylight only operating times (6 to 8 hours on Mars), relatively short operating lives depending on the operating environment, and rover/lander size and surface use constraints. Radioisotope power systems are being reconsidered for long-range science missions. Unfortunately, the high cost, political controversy, and launch difficulties that are associated with nuclear-based power systems suggests that the use of radioisotope powered landers, rovers, and EVA assistants will be limited. The third power system concept now being considered are fuel cell based systems. Fuel cell power systems overcome many of the performance and surface exploration limitations of solar array/battery power systems and the prohibitive cost and other difficulties associated with nuclear power systems for mobile applications. In an effort to better understand the capabilities and limitations of fuel cell power systems for Moon and Mars exploration applications, NASA is investigating the use of in-Situ Resource Utilization (ISRU) produced reactant, fuel cell based power plants to power robotic outpost rovers, science equipment, and future human spacecraft, surface-excursion rovers, and EVA assistant rovers. This paper will briefly compare the capabilities and limitations of fuel cell power systems relative to solar array/battery and nuclear systems, discuss the unique and enhanced missions that fuel cell power systems enable, and discuss the common technology and system attributes

  3. ISRU Reactant, Fuel Cell Based Power Plant for Robotic and Human Mobile Exploration Applications

    NASA Astrophysics Data System (ADS)

    Baird, Russell S.; Sanders, Gerald; Simon, Thomas; McCurdy, Kerri

    2003-01-01

    Three basic power generation system concepts are generally considered for lander, rover, and Extra-Vehicular Activity (EVA) assistant applications for robotic and human Moon and Mars exploration missions. The most common power system considered is the solar array and battery system. While relatively simple and successful, solar array/battery systems have some serious limitations for mobile applications. For typical rover applications, these limitations include relatively low total energy storage capabilities, daylight only operating times (6 to 8 hours on Mars), relatively short operating lives depending on the operating environment, and rover/lander size and surface use constraints. Radioisotope power systems are being reconsidered for long-range science missions. Unfortunately, the high cost, political controversy, and launch difficulties that are associated with nuclear-based power systems suggests that the use of radioisotope powered landers, rovers, and EVA assistants will be limited. The third power system concept now being considered are fuel cell based systems. Fuel cell power systems overcome many of the performance and surface exploration limitations of solar array/battery power systems and the prohibitive cost and other difficulties associated with nuclear power systems for mobile applications. In an effort to better understand the capabilities and limitations of fuel cell power systems for Moon and Mars exploration applications. NASA is investigating the use of In-Situ Resource Utilization (ISRU) produced reactant, fuel cell based power plants to power robotic outpost rovers, science equipment, and future human spacecraft, surface-excursion rovers, and EVA assistant rovers. This paper will briefly compare the capabilities and limitations of fuel cell power systems relative to solar array/battery and nuclear systems, discuss the unique and enhanced missions that fuel cell power systems enable, and discuss the common technology and system attributes

  4. Recovery Act. Solid Oxide Fuel Cell Diesel Auxilliary Power Unit Demonstration

    SciTech Connect

    Geiger, Gail E.

    2013-09-30

    Solid Oxide Fuel Cell Diesel Auxilliary Power Unit Demonstration Project. Summarizing development of Delphi’s next generation SOFC system as the core power plant to prove the viability of the market opportunity for a 3-5 kW diesel SOFC system. Report includes test and demonstration results from testing the diesel APU in a high visibility fleet customer vehicle application.

  5. Multi-objective optimization for hybrid fuel cells power system under uncertainty

    NASA Astrophysics Data System (ADS)

    Subramanyan, Karthik; Diwekar, Urmila M.; Goyal, Amit

    One of the major applications of fuel cells is as onsite stationary electric power plants. Several types of configurations have been hypothesized and tested for these kinds of applications at the conceptual level but hybrid power plants are one of the most efficient. These are designs that combine a fuel cell cycle with other thermodynamic cycles to provide higher efficiency. Generally, the heat rejected by the fuel cell at a higher temperature is used in a bottoming cycle to generate steam. In this work we are considering a conceptual design of a solid oxide fuel cell-proton exchange membrane (SOFC-PEM) fuel cell hybrid power plant [R. Geisbrecht, Compact Electrochemical Reformer Based on SOFC Technology, AIChE Spring National Meeting, Atlanta, GA, 2000] in which the high temperature SOFC fuel cell acts both as electricity producer and fuel reformer for the low temperature PEM fuel cell (PEMFC). The exhaust from the PEM fuel cell goes to a waste hydrogen burner and heat recovery steam generator that produces steam for further utilizations. Optimizing this conceptual design involves consideration of a number of objectives. The process should have low pollutant emissions as well as cost competitive with the existing technology. The solution of a multi-objective optimization problem is not a single solution but a complete non-dominated or Pareto set, which includes the alternatives representing potential compromise solutions among the objectives. This makes a range of choice available to decision makers and provides them with the trade-off information among the multiple objectives effectively. This paper presents the optimal trade-off design solutions or the Pareto set for this hybrid power plant through a multi-objective optimization framework. This hybrid technology is new and the system level models used for fuel cells performance have significant uncertainties in them. In this paper, we characterize these uncertainties and study the effect of these uncertainties

  6. Experimental study of a fuel cell power train for road transport application

    NASA Astrophysics Data System (ADS)

    Corbo, P.; Corcione, F. E.; Migliardini, F.; Veneri, O.

    The development of fuel cell electric vehicles requires the on-board integration of fuel cell systems and electric energy storage devices, with an appropriate energy management system. The optimization of performance and efficiency needs an experimental analysis of the power train, which has to be effected in both stationary and transient conditions (including standard driving cycles). In this paper experimental results concerning the performance of a fuel cell power train are reported and discussed. In particular characterization results for a small sized fuel cell system (FCS), based on a 2.5 kW PEM stack, alone and coupled to an electric propulsion chain of 3.7 kW are presented and discussed. The control unit of the FCS allowed the main stack operative parameters (stoichiometric ratio, hydrogen and air pressure, temperature) to be varied and regulated in order to obtain optimized polarization and efficiency curves. Experimental runs effected on the power train during standard driving cycles have allowed the performance and efficiency of the individual components (fuel cell stack and auxiliaries, dc-dc converter, traction batteries, electric engine) to be evaluated, evidencing the role of output current and voltage of the dc-dc converter in directing the energy flows within the propulsion system.

  7. Feasibility study of wood biomass gasification/molten carbonate fuel cell power system—comparative characterization of fuel cell and gas turbine systems

    NASA Astrophysics Data System (ADS)

    Morita, H.; Yoshiba, F.; Woudstra, N.; Hemmes, K.; Spliethoff, H.

    The conversion of biomass by means of gasification into a fuel suitable for a high-temperature fuel cell has recently received more attention as a potential substitute for fossil fuels in electric power production. However, combining biomass gasification with a high-temperature fuel cell raises many questions with regard to efficiency, feasibility and process requirements. In this study, a biomass gasification/molten carbonate fuel cell (MCFC) system is modelled and compared with a relatively well-established biomass gasification/gas turbine (GT), in order to understand the peculiarities of biomass gasification/MCFC power systems and to develop a reference MCFC system as a future biomass gasification/MCFC power station.

  8. A polymer electrolyte fuel cell stack for stationary power generation from hydrogen fuel

    SciTech Connect

    Zawodzinski, C.; Wilson, M.; Gottesfeld, S.

    1996-10-01

    The fuel cell is the most efficient device for the conversion of hydrogen fuel to electric power. As such, the fuel cell represents a key element in efforts to demonstrate and implement hydrogen fuel utilization for electric power generation. A central objective of a LANL/Industry collaborative effort supported by the Hydrogen Program is to integrate PEM fuel cell and novel stack designs at LANL with stack technology of H-Power Corporation (H-Power) in order to develop a manufacturable, low-cost/high-performance hydrogen/air fuel cell stack for stationary generation of electric power. A LANL/H-Power CRADA includes Tasks ranging from exchange, testing and optimization of membrane-electrode assemblies of large areas, development and demonstration of manufacturable flow field, backing and bipolar plate components, and testing of stacks at the 3-5 cell level and, finally, at the 4-5 kW level. The stack should demonstrate the basic features of manufacturability, overall low cost and high energy conversion efficiency. Plans for future work are to continue the CRADA work along the time line defined in a two-year program, to continue the LANL activities of developing and testing stainless steel hardware for longer term stability including testing in a stack, and to further enhance air cathode performance to achieve higher energy conversion efficiencies as required for stationary power application.

  9. Micro space power system using MEMS fuel cell for nano-satellites

    NASA Astrophysics Data System (ADS)

    Lee, Jongkwang; Kim, Taegyu

    2014-08-01

    A micro space power system using micro fuel cell was developed for nano-satellites. The power system was fabricated using microelectromechanical system (MEMS) fabrication technologies. Polymer electrolyte membrane (PEM) fuel cell was selected in consideration of space environment. Sodium borohydride (NaBH4) was selected as a hydrogen source while hydrogen peroxide (H2O2) was selected as an oxygen source. The power system consists of a micro fuel cell, micro-reactor, micro-pump, and fuel cartridges. The micro fuel cell was fabricated on a light-weight and corrosion-resistant glass plates. The micro-reactor was used to generate hydrogen from NaBH4 alkaline solution via a catalytic hydrolysis reaction. All components such as micro-pump, fuel cartridges, and auxiliary battery were integrated for a complete power system. The storability of NaBH4 solution was evaluated at -25 °C and the performance of the micro power system was measured at various operating conditions. The power output of micro power system reasonably followed up the given electric load conditions.

  10. Recent progress in zirconia-based fuel cells for power generation

    SciTech Connect

    Singhal, S.C.

    1992-01-01

    High temperature solid oxide fuel cells based upon yttria-stabilized zirconia electrolyte offer a clean, pollution-free technology to electrochemically generate electricity at high efficiencies. This paper reviews the designs, materials and fabrication processes used for such fuel cells. Most progress to date has been achieved with tubular geometry cells. A large number of tubular cells have been electrically tested, some to times up to 30,000 hours; these cells have shown excellent performance and performance stability. In addition, successively larger size electric generators utilizing these cells have been designed, built and operated since 1984. Two 25 kW power generation field test units have recently been fabricated; these units represent a major milestone in the commercialization of zirconia-based fuel cells for power generation.

  11. Recent progress in zirconia-based fuel cells for power generation

    SciTech Connect

    Singhal, S.C.

    1992-12-01

    High temperature solid oxide fuel cells based upon yttria-stabilized zirconia electrolyte offer a clean, pollution-free technology to electrochemically generate electricity at high efficiencies. This paper reviews the designs, materials and fabrication processes used for such fuel cells. Most progress to date has been achieved with tubular geometry cells. A large number of tubular cells have been electrically tested, some to times up to 30,000 hours; these cells have shown excellent performance and performance stability. In addition, successively larger size electric generators utilizing these cells have been designed, built and operated since 1984. Two 25 kW power generation field test units have recently been fabricated; these units represent a major milestone in the commercialization of zirconia-based fuel cells for power generation.

  12. Characteristics of candidate sites selected for onsite fuel cell power plant testing

    NASA Astrophysics Data System (ADS)

    Racine, W. C.; Ferraro, V. D.; Woods, R. R.

    A portion of the Onsite Fuel Cell Program involves field testing forty-nine, 40-kW onsite fuel cell power plants. This paper describes the energy characteristics of 82 different sites that have been selected as potential field test locations. The 82 sites include multi-family residential, commercial and light industrial buildings that represent 26 market segments throughout the United States and Japan. Each one of the 82 sites has been instrumented with a standard data acquisition system to obtain hourly thermal and electrical energy consumption data. This energy data will help determine each site's compatibility with a 40-kW fuel cell power plant, and will provide an extensive data base which may be useful in other energy studies.

  13. Simulation of gas and water management strategies in PEM fuel cells for UAV power

    NASA Astrophysics Data System (ADS)

    Wade, Nasir; Smith, Sonya

    2008-11-01

    Proton exchange membrane fuel cells (PEMFC) a involve a number of complex fluid phenomena that are not well understood. The focus of this research is to design a fuel cell that addresses the issues of gas and water management for the power requirements for an Unmanned Arial Vehicle (UAV). Often in conventional stack design, PEM fuel cells are connected electrically in series to create the desired voltage and feed from a common fuel or oxidant stream. This method of fueling, often leads to an uneven distribution of fluid within the stack, causing issues such as cell flooding, dehydration of membrane and inevitably poor fuel cell performance. Generally, fuel cell designers and developers incorporate higher stoichiometric gas flow rates and use flow field designs with high pressure drops in order to counter this phenomenon, ensuring even gas distribution. This method, although effective for water removal, leads to added cost and higher levels of wasted fuel. Using a simulation based approach we demonstrate the feasibility and effectiveness of an individual fuel and oxidant flow distribution, integrated with an individual sequential exhaust technique for a 6-8 cell stack which outputs 300-500 Watts of power. Using varied exhaust configurations the most optimal active gas management strategy will be outlined and recommended to give the best stack performance.

  14. Adaptive supervisory control strategy of a fuel cell/battery-powered city bus

    NASA Astrophysics Data System (ADS)

    Xu, Liangfei; Li, Jianqiu; Hua, Jianfeng; Li, Xiangjun; Ouyang, Minggao

    This paper presents an adaptive supervisory control strategy for a fuel cell/battery-powered city bus to fulfill the complex road conditions in Beijing bus routes. An equivalent consumption minimization strategy (ECMS) is firstly proposed to optimize the fuel economy. The adaptive supervisory control strategy is exploited based on this, incorporating an estimating algorithm for the vehicle accessorial power, an algorithm for the battery charge-sustaining and a Recursive Least Squares (RLS) algorithm for fuel cell performance identification. Finally, an adaptive supervisory controller (ASC) considering the fuel consumption minimization, the battery charge-sustaining and the fuel cell durability has been implemented within the hybrid city buses. Results in the "China city bus typical cycle" testing and the demonstrational program of Beijing bus routes are presented, demonstrating that this approach provides an improvement of fuel economy along with robustness and ease of implementation. However, the fuel cell system does not leave much room for the optimal strategy to promote the fuel economy. Benefits may also result in a prolongation of the fuel cell working life, which needs to be verified in future.

  15. High power density from Pt thin film electrodes based microbial fuel cell.

    PubMed

    Sharma, Tushar; Reddy, A Leela Mohana; Chandra, T S; Ramaprabhu, S

    2008-08-01

    Microbial Fuel Cells (MFC) are robust devices capable of taping biological energy, converting sugars into potential sources of energy. Persistent efforts are directed towards increasing power output. However, they have not been researched to the extent of making them competitive with chemical fuel cells. The power generated in a dual-chamber MFC using neutral red (NR) as the electron mediator has been previously shown to be 152.4 mW/m2 at 412.5 mA/m2 of current density. In the present work we show that Pt thin film coated carbon paper as electrodes increase the performance of a microbial fuel cell compared to conventionally employed electrodes. The results obtained using E. coli based microbial fuel cell with methylene blue and neutral red as the electron mediator, potassium ferricyanide in the cathode compartment were systematically studied and the results obtained with Pt thin film coated over carbon paper as electrodes were compared with that of graphite electrodes. Platinum coated carbon electrodes were found to be better over the previously used for microbial fuel cells and at the same time are cheaper than the preferred pure platinum electrodes. PMID:19049189

  16. Advanced power systems featuring a closely coupled catalytic gasification carbonate fuel cell plant

    SciTech Connect

    Steinfeld, G.; Wilson, W.G.

    1993-01-01

    Pursuing the key national goal of clean and efficient uulization of the abundant domestic coal resources for power generation, a study was conducted with DOE/METC support to evaluate the potential of integrated gasification/carbonate fuel cell power generation systems. By closely coupling the fuel cell with the operation of a catalytic gasifier, the advantages of both the catalytic gasification and the high efficiency fuel cell complement each other, resulting in a power plant system with unsurpassed efficiencies approaching 55% (HHV). Low temperature catalytic gasification producing a high methane fuel gas offers the potential for high gas efficiencies by operating with minimal or no combustion. Heat required for gasification is provided by combination of recycle from the fuel cell and exothermic methanation and shift reactions. Air can be supplemented if required. In combination with internally reforming carbonate fuel cells, low temperature catalytic gasification can achieve very attractive system efficiencies while producing extremely low emissions compared to conventional plants utilizing coal. Three system configurations based on recoverable and disposable gasification catalysts were studied. Experimental tests were conducted to evaluate these gasification catalysts. The recoverable catalyst studied was potassium carbonate, and the disposable catalysts were calcium in the form of limestone and iron in the form of taconite. Reactivities of limestone and iron were lower than that of potassium, but were improved by using the catalyst in solution form. Promising results were obtained in the system evaluations as well as the experimental testing of the gasification catalysts. To realize the potential of these high efficiency power plant systems more effort is required to develop catalytic gasification systems and their integration with carbonate fuel cells.

  17. Advanced power systems featuring a closely coupled catalytic gasification carbonate fuel cell plant

    SciTech Connect

    Steinfeld, G.; Wilson, W.G.

    1993-06-01

    Pursuing the key national goal of clean and efficient uulization of the abundant domestic coal resources for power generation, a study was conducted with DOE/METC support to evaluate the potential of integrated gasification/carbonate fuel cell power generation systems. By closely coupling the fuel cell with the operation of a catalytic gasifier, the advantages of both the catalytic gasification and the high efficiency fuel cell complement each other, resulting in a power plant system with unsurpassed efficiencies approaching 55% (HHV). Low temperature catalytic gasification producing a high methane fuel gas offers the potential for high gas efficiencies by operating with minimal or no combustion. Heat required for gasification is provided by combination of recycle from the fuel cell and exothermic methanation and shift reactions. Air can be supplemented if required. In combination with internally reforming carbonate fuel cells, low temperature catalytic gasification can achieve very attractive system efficiencies while producing extremely low emissions compared to conventional plants utilizing coal. Three system configurations based on recoverable and disposable gasification catalysts were studied. Experimental tests were conducted to evaluate these gasification catalysts. The recoverable catalyst studied was potassium carbonate, and the disposable catalysts were calcium in the form of limestone and iron in the form of taconite. Reactivities of limestone and iron were lower than that of potassium, but were improved by using the catalyst in solution form. Promising results were obtained in the system evaluations as well as the experimental testing of the gasification catalysts. To realize the potential of these high efficiency power plant systems more effort is required to develop catalytic gasification systems and their integration with carbonate fuel cells.

  18. Self-powered supercapacitive microbial fuel cell: The ultimate way of boosting and harvesting power.

    PubMed

    Santoro, Carlo; Soavi, Francesca; Serov, Alexey; Arbizzani, Catia; Atanassov, Plamen

    2016-04-15

    In this work, for the first time, we demonstrate a supercapacitive microbial fuel cell which integrates the energy harvesting function of a microbial fuel cell (MFC) with the high-power operation of an internal supercapacitor. The pursued strategies are: (i) the increase of the cell voltage by the use of high potential cathodes like bilirubin oxidase (BOx) or iron-aminoantipyrine (Fe-AAPyr); (ii) the use of an additional capacitive electrode (additional electrode, AdE) which is short-circuited with the MFC cathode and coupled with the MFC anode (MFC-AdE). The high working potential of BOx cathode and the low impedances of the additional capacitive electrode and the MFC anode permitted to achieve up to 19 mW (84.4 Wm(-2), 152 Wm(-3)), the highest power value ever reported for MFCs. Exploiting the supercapacitive properties of the MFC electrodes allows the system to be simpler, cheaper and more efficient without additional electronics management added with respect to an MFC/external supercapacitor coupling. The use of the AdE makes it possible to decouple energy and power and to achieve recharge times in the order of few seconds making the system appealing for practical applications. PMID:26615513

  19. Metal Interconnects for Solid Oxide Fuel Cell Power Systems

    SciTech Connect

    S. Elangovan

    2006-04-01

    Interconnect development is identified by the US Department of energy as a key technical area requiring focused research to meet the performance and cost goals under the Solid State Energy Conversion Alliance initiative. In the Phase I SECA Core Technology Program, Ceramatec investigated a commercial ferritic stainless steel composition for oxidation resistance properties by measuring the weight gain when exposed to air at the fuel cell operating temperature. A pre-treatment process that results in a dense, adherent scale was found to reduce the oxide scale growth rate significantly. A process for coating the surface of the alloy in order to reduce the in-plane resistance and potentially inhibit chromium oxide evaporation was also identified. The combination of treatments provided a very low resistance through the scale. The resistance measured was as low as 10 milliohm-cm2 at 750 C in air. The oxide scale was also found to be stable in humidified air at 750 C. The resistance value was stable over several thermal cycles. A similar treatment and coating for the fuel side of the interconnect also showed an exceptionally low resistance of one milliohm-cm2 in humidified hydrogen at 750 c, and was stable through multiple thermal cycles. Measurement of interconnect resistance when it was exposed to both air and humidified hydrogen on opposite sides also showed low, stable resistance after additional modification to the pre-treatment process. Resistance stacks, using an interconnect stack with realistic gas flows, also provided favorable results. Chromium evaporation issue however requires testing of fuel stacks and was outside of the scope of this project. based on results to-date, the alloy selection and the treatment processes appear to be well suited for SOFC interconnect application.

  20. A practical PEM fuel cell model for simulating vehicle power sources

    SciTech Connect

    Amphlett, J.C.; Mann, R.F.; Peppley, B.A.; Roberge, P.R.; Rodrigues, A.

    1995-07-01

    The interest in fuel cell technology as an alternative to internal combustion engines is growing rapidly with the increased concern with environmental issues such s reducing vehicle emissions. Fuel cells offer a power source which produces electrical energy from fuel and oxidant which produce little or no emissions. Fuel cell power sources are being considered for both terrestrial and marine applications. The research and commercialization of such systems require system modeling to determine performance levels and fuel and oxidant requirements. A practical model will have to be flexible in its calculations depending on the information available. A model predicting the performance of a proton exchange membrane fuel cell has been developed for a Ballard Mark V 5 kW 35-cell stack. The parametric model combining both empirical and mechanistic qualities was developed to calculate the cell voltage output in terms of complex relationships between current, stack temperature, and inlet partial pressure of hydrogen and oxygen. The model utilizes an iterative computer solution to obtain a practical flexible model which could calculate any variable in terms of the others. This paper illustrates the use of a practical model to determine the fuel and oxidant requirements to achieve various levels of power required for different vehicle power supplies. Applications to automobiles, buses, locomotives, ships, submarines, and unmanned underwater vehicles with power supplies of 3--3,000 kW were investigated.

  1. Reformers for the production of hydrogen from methanol and alternative fuels for fuel cell powered vehicles

    SciTech Connect

    Kumar, R.; Ahmed, S.; Krumpelt, M.; Myles, K.M.

    1992-08-01

    The objective of this study was (i) to assess the present state of technology of reformers that convert methanol (or other alternative fuels) to a hydrogen-rich gas mixture for use in a fuel cell, and (ii) to identify the R&D needs for developing reformers for transportation applications. Steam reforming and partial oxidation are the two basic types of fuel reforming processes. The former is endothermic while the latter is exothermic. Reformers are therefore typically designed as heat exchange systems, and the variety of designs used includes shell-and-tube, packed bed, annular, plate, and cyclic bed types. Catalysts used include noble metals and oxides of Cu, Zn, Cr, Al, Ni, and La. For transportation applications a reformer must be compact, lightweight, and rugged. It must also be capable of rapid start-up and good dynamic performance responsive to fluctuating loads. A partial oxidation reformer is likely to be better than a steam reformer based on these considerations, although its fuel conversion efficiency is expected to be lower than that of a steam reformer. A steam reformer better lends itself to thermal integration with the fuel cell system; however, the thermal independence of the reformer from the fuel cell stack is likely to yield much better dynamic performance of the reformer and the fuel cell propulsion power system. For both steam reforming and partial oxidation reforming, research is needed to develop compact, fast start-up, and dynamically responsive reformers. For transportation applications, steam reformers are likely to prove best for fuel cell/battery hybrid power systems, and partial oxidation reformers are likely to be the choice for stand-alone fuel cell power systems.

  2. Reformers for the production of hydrogen from methanol and alternative fuels for fuel cell powered vehicles

    SciTech Connect

    Kumar, R.; Ahmed, S.; Krumpelt, M.; Myles, K.M.

    1992-08-01

    The objective of this study was (i) to assess the present state of technology of reformers that convert methanol (or other alternative fuels) to a hydrogen-rich gas mixture for use in a fuel cell, and (ii) to identify the R D needs for developing reformers for transportation applications. Steam reforming and partial oxidation are the two basic types of fuel reforming processes. The former is endothermic while the latter is exothermic. Reformers are therefore typically designed as heat exchange systems, and the variety of designs used includes shell-and-tube, packed bed, annular, plate, and cyclic bed types. Catalysts used include noble metals and oxides of Cu, Zn, Cr, Al, Ni, and La. For transportation applications a reformer must be compact, lightweight, and rugged. It must also be capable of rapid start-up and good dynamic performance responsive to fluctuating loads. A partial oxidation reformer is likely to be better than a steam reformer based on these considerations, although its fuel conversion efficiency is expected to be lower than that of a steam reformer. A steam reformer better lends itself to thermal integration with the fuel cell system; however, the thermal independence of the reformer from the fuel cell stack is likely to yield much better dynamic performance of the reformer and the fuel cell propulsion power system. For both steam reforming and partial oxidation reforming, research is needed to develop compact, fast start-up, and dynamically responsive reformers. For transportation applications, steam reformers are likely to prove best for fuel cell/battery hybrid power systems, and partial oxidation reformers are likely to be the choice for stand-alone fuel cell power systems.

  3. Low-temperature fuel cell systems for commercial airplane auxiliary power.

    SciTech Connect

    Curgus, Dita Brigitte; Pratt, Joseph William; Akhil, Abbas Ali; Klebanoff, Leonard E.

    2010-11-01

    This presentation briefly describes the ongoing study of fuel cell systems on-board a commercial airplane. Sandia's current project is focused on Proton Exchange Membrane (PEM) fuel cells applied to specific on-board electrical power needs. They are trying to understand how having a fuel cell on an airplane would affect overall performance. The fuel required to accomplish a mission is used to quantify the performance. Our analysis shows the differences between the base airplane and the airplane with the fuel cell. There are many ways of designing a system, depending on what you do with the waste heat. A system that requires ram air cooling has a large mass penalty due to increased drag. The bottom-line impact can be expressed as additional fuel required to complete the mission. Early results suggest PEM fuel cells can be used on airplanes with manageable performance impact if heat is rejected properly. For PEMs on aircraft, we are continuing to perform: (1) thermodynamic analysis (investigate configurations); (2) integrated electrical design (with dynamic modeling of the micro grid); (3) hardware assessment (performance, weight, and volume); and (4) galley and peaker application.

  4. Power generation in fuel cells using liquid methanol and hydrogen peroxide

    NASA Technical Reports Server (NTRS)

    Narayanan, Sekharipuram R. (Inventor); Valdez, Thomas I. (Inventor); Chun, William (Inventor)

    2002-01-01

    The invention is directed to an encapsulated fuel cell including a methanol source that feeds liquid methanol (CH.sub.3 OH) to an anode. The anode is electrical communication with a load that provides electrical power. The fuel cell also includes a hydrogen peroxide source that feeds liquid hydrogen peroxide (H.sub.2 O.sub.2) to the cathode. The cathode is also in communication with the electrical load. The anode and cathode are in contact with and separated by a proton-conducting polymer electrolyte membrane.

  5. Transport dynamics of a high-power-density matrix-type hydrogen-oxygen fuel cell

    NASA Technical Reports Server (NTRS)

    Prokopius, P. R.; Hagedorn, N. H.

    1974-01-01

    Experimental transport dynamics tests were made on a space power fuel cell of current design. Various operating transients were introduced and transport-related response data were recorded with fluidic humidity sensing instruments. Also, sampled data techniques were developed for measuring the cathode-side electrolyte concentration during transient operation.

  6. Fuel Cell-Powered Go-Kart: Project Mimics Real-World Product Development

    ERIC Educational Resources Information Center

    Fuller, Amanda

    2010-01-01

    Five years ago, Leon Strecker's technology education class at Darien High School came up with the idea of building a fuel cell-powered go-kart. In previous years, the class had worked on other creations, such as electric cars that competed in a state-sponsored race and a full-size hovercraft. But students had not taken on anything anywhere near…

  7. Manual of phosphoric acid fuel cell power plant cost model and computer program

    NASA Technical Reports Server (NTRS)

    Lu, C. Y.; Alkasab, K. A.

    1984-01-01

    Cost analysis of phosphoric acid fuel cell power plant includes two parts: a method for estimation of system capital costs, and an economic analysis which determines the levelized annual cost of operating the system used in the capital cost estimation. A FORTRAN computer has been developed for this cost analysis.

  8. ENERGY PRODUCTION AND POLLUTION PREVENTION AT SEWAGE TREATMENT PLANTS USING FUEL CELL POWER PLANTS

    EPA Science Inventory

    The paper discusses energy production and pollution prevention at sewage treatment plants using fuel cell power plants. Anaerobic digester gas (ADG) is produced at waste water treatment plants during the anaerobic treatment of sewage to reduce solids. The major constituents are...

  9. Method for reducing fuel cell output voltage to permit low power operation

    DOEpatents

    Reiser, Carl A.; Landau, Michael B.

    1980-01-01

    Fuel cell performance is degraded by recycling a portion of the cathode exhaust through the cells and, if necessary, also reducing the total air flow to the cells for the purpose of permitting operation below a power level which would otherwise result in excessive voltage.

  10. ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT: UTC FUEL CELLS' PC25C POWER PLANT - GAS PROCESSING UNIT PERFORMANCE FOR ANAEROBIC DIGESTER GAS

    EPA Science Inventory

    Under EPA’s Environmental Technology Verification program, which provides objective and scientific third party analysis of new technology that can benefit the environment, a combined heat and power system based on the UTC Fuel Cell's PC25C Fuel Cell Power Plant was evaluated. The...

  11. Fuel Cell Power Model Version 2: Startup Guide, System Designs, and Case Studies. Modeling Electricity, Heat, and Hydrogen Generation from Fuel Cell-Based Distributed Energy Systems

    SciTech Connect

    Steward, D.; Penev, M.; Saur, G.; Becker, W.; Zuboy, J.

    2013-06-01

    This guide helps users get started with the U.S. Department of Energy/National Renewable Energy Laboratory Fuel Cell Power (FCPower) Model Version 2, which is a Microsoft Excel workbook that analyzes the technical and economic aspects of high-temperature fuel cell-based distributed energy systems with the aim of providing consistent, transparent, comparable results. This type of energy system would provide onsite-generated heat and electricity to large end users such as hospitals and office complexes. The hydrogen produced could be used for fueling vehicles or stored for later conversion to electricity.

  12. MOLTEN CARBONATE FUEL CELL POWER PLANT LOCATED AT TERMINAL ISLAND WASTEWATER TREATMENT PLANT

    SciTech Connect

    William W. Glauz

    2004-09-01

    The Los Angeles Department of Water and Power (LADWP) has developed one of the most recognized fuel cell demonstration programs in the United States. In addition to their high efficiencies and superior environmental performance, fuel cells and other generating technologies that can be located at or near the load, offers several electric utility benefits. Fuel cells can help further reduce costs by reducing peak electricity demand, thereby deferring or avoiding expenses for additional electric utility infrastructure. By locating generators near the load, higher reliability of service is possible and the losses that occur during delivery of electricity from remote generators are avoided. The potential to use renewable and locally available fuels, such as landfill or sewage treatment waste gases, provides another attractive outlook. In Los Angeles, there are also many oil producing areas where the gas by-product can be utilized. In June 2000, the LADWP contracted with FCE to install and commission the precommercial 250kW MCFC power plant. The plant was delivered, installed, and began power production at the JFB in August 2001. The plant underwent manufacturer's field trials up for 18 months and was replace with a commercial plant in January 2003. In January 2001, the LADWP contracted with FCE to provide two additional 250kW MCFC power plants. These commercial plants began operations during mid-2003. The locations of these plants are at the Terminal Island Sewage Treatment Plant at the Los Angeles Harbor (for eventual operation on digester gas) and at the LADWP Main Street Service Center east of downtown Los Angeles. All three carbonate fuel cell plants received partial funding through the Department of Defense's Climate Change Fuel Cell Buydown Program. This report covers the technical evaluation and benefit-cost evaluation of the Terminal Island 250kW MCFC power plant during its first year of operation from June 2003 to July 2004.

  13. Energy management of fuel cell/solar cell/supercapacitor hybrid power source

    NASA Astrophysics Data System (ADS)

    Thounthong, Phatiphat; Chunkag, Viboon; Sethakul, Panarit; Sikkabut, Suwat; Pierfederici, Serge; Davat, Bernard

    This study presents an original control algorithm for a hybrid energy system with a renewable energy source, namely, a polymer electrolyte membrane fuel cell (PEMFC) and a photovoltaic (PV) array. A single storage device, i.e., a supercapacitor (ultracapacitor) module, is in the proposed structure. The main weak point of fuel cells (FCs) is slow dynamics because the power slope is limited to prevent fuel starvation problems, improve performance and increase lifetime. The very fast power response and high specific power of a supercapacitor complements the slower power output of the main source to produce the compatibility and performance characteristics needed in a load. The energy in the system is balanced by d.c.-bus energy regulation (or indirect voltage regulation). A supercapacitor module functions by supplying energy to regulate the d.c.-bus energy. The fuel cell, as a slow dynamic source in this system, supplies energy to the supercapacitor module in order to keep it charged. The photovoltaic array assists the fuel cell during daytime. To verify the proposed principle, a hardware system is realized with analog circuits for the fuel cell, solar cell and supercapacitor current control loops, and with numerical calculation (dSPACE) for the energy control loops. Experimental results with small-scale devices, namely, a PEMFC (1200 W, 46 A) manufactured by the Ballard Power System Company, a photovoltaic array (800 W, 31 A) manufactured by the Ekarat Solar Company and a supercapacitor module (100 F, 32 V) manufactured by the Maxwell Technologies Company, illustrate the excellent energy-management scheme during load cycles.

  14. High efficiency direct fuel cell hybrid power cycle for near term application

    SciTech Connect

    Steinfeld, G.; Maru, H.C.; Sanderson, R.A.

    1996-12-31

    Direct carbonate fuel cells being developed by Energy Research Corporation can generate power at an efficiency approaching 60% LHV. This unique fuel cell technology can consume natural gas and other hydrocarbon based fuels directly without requiring an external reformer, thus providing a simpler and inherently efficient power generation system. A 2 MW power plant demonstration of this technology has been initiated at an installation in the city of Santa Clara in California. A 2.85 MW commercial configuration shown in Figure 1 is presently being developed. The complete plant includes the carbonate fuel cell modules, an inverter, transformer and switchgear, a heat recovery unit and supporting instrument air and water treatment systems. The emission levels for this 2.85 MW plant are projected to be orders of magnitude below existing or proposed standards. The 30 year levelized cost of electricity, without inflation, is projected to be approximately 5{cents}/kW-h assuming capital cost for the carbonate fuel cell system of $1000/kW.

  15. Configuring a fuel cell based residential combined heat and power system

    NASA Astrophysics Data System (ADS)

    Ahmed, Shabbir; Papadias, Dionissios D.; Ahluwalia, Rajesh K.

    2013-11-01

    The design and performance of a fuel cell based residential combined heat and power (CHP) system operating on natural gas has been analyzed. The natural gas is first converted to a hydrogen-rich reformate in a steam reformer based fuel processor, and the hydrogen is then electrochemically oxidized in a low temperature polymer electrolyte fuel cell to generate electric power. The heat generated in the fuel cell and the available heat in the exhaust gas is recovered to meet residential needs for hot water and space heating. Two fuel processor configurations have been studied. One of the configurations was explored to quantify the effects of design and operating parameters, which include pressure, temperature, and steam-to-carbon ratio in the fuel processor, and fuel utilization in the fuel cell. The second configuration applied the lessons from the study of the first configuration to increase the CHP efficiency. Results from the two configurations allow a quantitative comparison of the design alternatives. The analyses showed that these systems can operate at electrical efficiencies of ∼46% and combined heat and power efficiencies of ∼90%.

  16. A direct methanol fuel cell system to power a humanoid robot

    NASA Astrophysics Data System (ADS)

    Joh, Han-Ik; Ha, Tae Jung; Hwang, Sang Youp; Kim, Jong-Ho; Chae, Seung-Hoon; Cho, Jae Hyung; Prabhuram, Joghee; Kim, Soo-Kil; Lim, Tae-Hoon; Cho, Baek-Kyu; Oh, Jun-Ho; Moon, Sang Heup; Ha, Heung Yong

    In this study, a direct methanol fuel cell (DMFC) system, which is the first of its kind, has been developed to power a humanoid robot. The DMFC system consists of a stack, a balance of plant (BOP), a power management unit (PMU), and a back-up battery. The stack has 42 unit cells and is able to produce about 400 W at 19.3 V. The robot is 125 cm tall, weighs 56 kg, and consumes 210 W during normal operation. The robot is integrated with the DMFC system that powers the robot in a stable manner for more than 2 h. The power consumption by the robot during various motions is studied, and load sharing between the fuel cell and the back-up battery is also observed. The loss of methanol feed due to crossover and evaporation amounts to 32.0% and the efficiency of the DMFC system in terms of net electric power is 22.0%.

  17. High performance monolithic power management system with dynamic maximum power point tracking for microbial fuel cells.

    PubMed

    Erbay, Celal; Carreon-Bautista, Salvador; Sanchez-Sinencio, Edgar; Han, Arum

    2014-12-01

    Microbial fuel cell (MFC) that can directly generate electricity from organic waste or biomass is a promising renewable and clean technology. However, low power and low voltage output of MFCs typically do not allow directly operating most electrical applications, whether it is supplementing electricity to wastewater treatment plants or for powering autonomous wireless sensor networks. Power management systems (PMSs) can overcome this limitation by boosting the MFC output voltage and managing the power for maximum efficiency. We present a monolithic low-power-consuming PMS integrated circuit (IC) chip capable of dynamic maximum power point tracking (MPPT) to maximize the extracted power from MFCs, regardless of the power and voltage fluctuations from MFCs over time. The proposed PMS continuously detects the maximum power point (MPP) of the MFC and matches the load impedance of the PMS for maximum efficiency. The system also operates autonomously by directly drawing power from the MFC itself without any external power. The overall system efficiency, defined as the ratio between input energy from the MFC and output energy stored into the supercapacitor of the PMS, was 30%. As a demonstration, the PMS connected to a 240 mL two-chamber MFC (generating 0.4 V and 512 μW at MPP) successfully powered a wireless temperature sensor that requires a voltage of 2.5 V and consumes power of 85 mW each time it transmit the sensor data, and successfully transmitted a sensor reading every 7.5 min. The PMS also efficiently managed the power output of a lower-power producing MFC, demonstrating that the PMS works efficiently at various MFC power output level. PMID:25365216

  18. Reliability considerations of a fuel cell backup power system for telecom applications

    NASA Astrophysics Data System (ADS)

    Serincan, Mustafa Fazil

    2016-03-01

    A commercial fuel cell backup power unit is tested in real life operating conditions at a base station of a Turkish telecom operator. The fuel cell system responds to 256 of 260 electric power outages successfully, providing the required power to the base station. Reliability of the fuel cell backup power unit is found to be 98.5% at the system level. On the other hand, a qualitative reliability analysis at the component level is carried out. Implications of the power management algorithm on reliability is discussed. Moreover, integration of the backup power unit to the base station ecosystem is reviewed in the context of reliability. Impact of inverter design on the stability of the output power is outlined. Significant current harmonics are encountered when a generic inverter is used. However, ripples are attenuated significantly when a custom design inverter is used. Further, fault conditions are considered for real world case studies such as running out of hydrogen, a malfunction in the system, or an unprecedented operating scheme. Some design guidelines are suggested for hybridization of the backup power unit for an uninterrupted operation.

  19. Simulation and system analysis of an ethanol fuel processor/PEM fuel cell power plant

    SciTech Connect

    Amphlett, J.C.; Leclerc, S.; Mann, R.F.; Peppley, B.A.; Roberge, P.R.

    1998-07-01

    Proton-exchange membrane (PEM) fuel cell systems offer a potential power source for utility and mobile applications. Currently, practical fuel cell systems use fuel processors for the production of a hydrogen-rich gas for the fuel cell anode. Liquid fuels such as ethanol, which can be produced from renewable feed stocks, are attractive options as feeds to a fuel processor. The generation of hydrogen gas for fuel cells, in most cases, becomes the crucial design issue with respect to weight and volume in these applications. Furthermore, these fuel processors require a gas clean-up system to ensure that the fuel quality meets the demands of the cell anode. The endothermic nature of the reformer will have a significant effect on the overall system efficiency. The gas clean-up system may also significantly affect the overall heat balance. A model of a methanol steam reformer that was previously developed has been used as the basis for a model for an ethanol steam reformer. Similarly, a steady-state electrochemical fuel cell model (SSEM) that was previously developed was used. A palladium diffuser purifier simulation was used for gas clean-up. The ethanol fuel processor model and the SSEM have been incorporated into a process simulation and system analysis of an ethanol-fueled reformer/fuel cell system. The performance of this complete system has been investigated for a variety of operating conditions. Assuming that ethanol reforming could be done at 400 C, a net electrical efficiency based on the LHV of ethanol of approximately 54% was calculated. The efficiency, however, is very sensitive to reforming temperature and drops rapidly as the reformer temperature increases. The fractional recovery of hydrogen by the gas clean-up system is also an important factor. The net thermal efficiency passes through a maximum at the point when the heating value in the retentate from the purifier just meets the endothermic heating requirements of the reformer.

  20. A New Hybrid Proton-Exchange-Membrane Fuel Cells-Battery Power System with Efficiencies Considered

    NASA Astrophysics Data System (ADS)

    Chao, Chung-Hsing; Shieh, Jenn-Jong

    Hybrid systems, based on lead-acid or lithium-ion batteries and proton-exchange-membrane fuel cells (PEMFCs), give the possibility of combining the benefit of both technologies. The merits of high energy density and power density for different applications are discussed in this paper in recognition of the practical realization of such hybrid power systems. Furthermore, experimental data for such a hybrid system is described and the results are shown and discussed. The results show that the combination of lead-acid batteries or lithium-ion batteries and PEMFCs shows advantages in cases of applications with high peak power requirements, such as electric scooters and applications where the fuel cell (FC) is used as an auxiliary power-supply to recharge the battery. The high efficiency of FCs operating with a partial load results in a good fuel economy for the purpose of recharging batteries within a FC system.

  1. Fuel Cells

    ERIC Educational Resources Information Center

    Hawkins, M. D.

    1973-01-01

    Discusses the theories, construction, operation, types, and advantages of fuel cells developed by the American space programs. Indicates that the cell is an ideal small-scale power source characterized by its compactness, high efficiency, reliability, and freedom from polluting fumes. (CC)

  2. Solid Oxide Fuel Cell/Gas Turbine Hybrid Cycle Technology for Auxiliary Aerospace Power

    NASA Technical Reports Server (NTRS)

    Steffen, Christopher J., Jr.; Freeh, Joshua E.; Larosiliere, Louis M.

    2005-01-01

    A notional 440 kW auxiliary power unit has been developed for 300 passenger commercial transport aircraft in 2015AD. A hybrid engine using solid-oxide fuel cell stacks and a gas turbine bottoming cycle has been considered. Steady-state performance analysis during cruise operation has been presented. Trades between performance efficiency and system mass were conducted with system specific energy as the discriminator. Fuel cell performance was examined with an area specific resistance. The ratio of fuel cell versus turbine power was explored through variable fuel utilization. Area specific resistance, fuel utilization, and mission length had interacting effects upon system specific energy. During cruise operation, the simple cycle fuel cell/gas turbine hybrid was not able to outperform current turbine-driven generators for system specific energy, despite a significant improvement in system efficiency. This was due in part to the increased mass of the hybrid engine, and the increased water flow required for on-board fuel reformation. Two planar, anode-supported cell design concepts were considered. Designs that seek to minimize the metallic interconnect layer mass were seen to have a large effect upon the system mass estimates.

  3. Development of reversible solid oxide fuel cell for power generation and hydrogen production

    NASA Astrophysics Data System (ADS)

    Jung, G. B.; Chen, J. Y.; Lin, C. Y.; Chan, S. H.

    2011-06-01

    A reversible solid oxide fuel cell (RSOFC) provides the dual function of performing energy storage and power generation, all in one unit. When functioning as an energy storage device, the RSOFC acts like an electrolyzer in water electrolysis mode; whereby the electric energy is stored as (electrolyzed) hydrogen and oxygen gases. While hydrogen is useful as a transportation fuel and in other industrial applications, the RSOFC also acts as a fuel cell in power generation mode to produce electricity when needed. The RSOFC would be a competitive technology in the upcoming hydrogen economy on the basis of its low cost, simple structure, and high efficiency. This paper reports on the design and manufacturing of its membrane electrode assembly using commercially available materials. Also reported are the resulting performance, both in electrolysis and fuel cell modes, as a function of its operating parameters such as temperature and current density. We found that the RSOFC performance improved with increasing temperature and its fuel cell mode had a better performance than its electrolysis mode due to a limited humidity inlet causing concentration polarization.

  4. Microbial fuel cells as power supply of a low-power temperature sensor

    NASA Astrophysics Data System (ADS)

    Khaled, Firas; Ondel, Olivier; Allard, Bruno

    2016-02-01

    Microbial fuel cells (MFCs) show great promise as a concomitant process for water treatment and as renewable energy sources for environmental sensors. The small energy produced by MFCs and the low output voltage limit the applications of MFCs. Specific converter topologies are required to step-up the output voltage of a MFC. A Power Management Unit (PMU) is proposed for operation at low input voltage and at very low power in a completely autonomous way to capture energy from MFCs with the highest possible efficiency. The application of sensors for monitoring systems in remote locations is an important approach. MFCs could be an alternative energy source in this case. Powering a sensor with MFCs may prove the fact that wastewater may be partly turned into renewable energy for realistic applications. The Power Management Unit is demonstrated for 3.6 V output voltage at 1 mW continuous power, based on a low-cost 0.7-L MFC. A temperature sensor may operate continuously on 2-MFCs in continuous flow mode. A flyback converter under discontinuous conduction mode is also tested to power the sensor. One continuously fed MFC was able to efficiently and continuously power the sensor.

  5. Water rocket - Electrolysis propulsion and fuel cell power

    SciTech Connect

    Carter, P H; Dittman, M D; Kare, J T; Militsky, F; Myers, B; Weisberg, A H

    1999-07-24

    Water Rocket is the collective name for an integrated set of technologies that offer new options for spacecraft propulsion, power, energy storage, and structure. Low pressure water stored on the spacecraft is electrolyzed to generate, separate, and pressurize gaseous hydrogen and oxygen. These gases, stored in lightweight pressure tanks, can be burned to generate thrust or recombined to produce electric power. As a rocket propulsion system, Water Rocket provides the highest feasible chemical specific impulse (-400 seconds). Even higher specific impulse propulsion can be achieved by combining Water Rocket with other advanced propulsion technologies, such as arcjet or electric thrusters. With innovative pressure tank technology, Water Rocket's specific energy [Wh/kg] can exceed that of the best foreseeable batteries by an order of magnitude, and the tanks can often serve as vehicle structural elements. For pulsed power applications, Water Rocket propellants can be used to drive very high power density generators, such as MHD devices or detonation-driven pulse generators. A space vehicle using Water Rocket propulsion can be totally inert and non-hazardous during assembly and launch. These features are particularly important for the timely development and flight qualification of new classes of spacecraft, such as microsats, nanosats, and refuelable spacecraft.

  6. Dynamic modeling and evaluation of solid oxide fuel cell - combined heat and power system operating strategies

    NASA Astrophysics Data System (ADS)

    Nanaeda, Kimihiro; Mueller, Fabian; Brouwer, Jacob; Samuelsen, Scott

    Operating strategies of solid oxide fuel cell (SOFC) combined heat and power (CHP) systems are developed and evaluated from a utility, and end-user perspective using a fully integrated SOFC-CHP system dynamic model that resolves the physical states, thermal integration and overall efficiency of the system. The model can be modified for any SOFC-CHP system, but the present analysis is applied to a hotel in southern California based on measured electric and heating loads. Analysis indicates that combined heat and power systems can be operated to benefit both the end-users and the utility, providing more efficient electric generation as well as grid ancillary services, namely dispatchable urban power. Design and operating strategies considered in the paper include optimal sizing of the fuel cell, thermal energy storage to dispatch heat, and operating the fuel cell to provide flexible grid power. Analysis results indicate that with a 13.1% average increase in price-of-electricity (POE), the system can provide the grid with a 50% operating range of dispatchable urban power at an overall thermal efficiency of 80%. This grid-support operating mode increases the operational flexibility of the SOFC-CHP system, which may make the technology an important utility asset for accommodating the increased penetration of intermittent renewable power.

  7. Onsite 40-kilowatt fuel cell power plant manufacturing and field test program

    NASA Technical Reports Server (NTRS)

    1985-01-01

    A joint Gas Research Institute and U.S. Department of Energy Program was initiated in 1982 to evaluate the use of fuel cell power systems for on-site energy service. Forty-six 40 kW fuel cell power plants were manufactured at the United Technologies Corporation facility in South Windsor, Connecticut, and are being delivered to host utilities and other program participants in the United States and Japan for field testing. The construction of the 46 fully-integrated power plants was completed in January 1985 within the constraints of the contract plan. The program has provided significant experience in the manufacture, acceptance testing, deployment, and support of on-site fuel cell systems. Initial field test results also show that these experimental power plants meet the performance and environmental requirements of a commercial specification. This Interim Report encompasses the design and manufacturing phases of the 40 kW Power Plant Manufacturing and Field Test program. The contract between UTC and NASA also provides UTC field engineering support to the host utilities, training programs and associated manuals for utility operating and maintenance personnel, spare parts support for a defined test period, and testing at UTC of a power plant made available from a preceding program phase. These activities are ongoing and will be reported subsequently.

  8. Onsite 40-kilowatt fuel cell power plant manufacturing and field test program

    NASA Astrophysics Data System (ADS)

    1985-02-01

    A joint Gas Research Institute and U.S. Department of Energy Program was initiated in 1982 to evaluate the use of fuel cell power systems for on-site energy service. Forty-six 40 kW fuel cell power plants were manufactured at the United Technologies Corporation facility in South Windsor, Connecticut, and are being delivered to host utilities and other program participants in the United States and Japan for field testing. The construction of the 46 fully-integrated power plants was completed in January 1985 within the constraints of the contract plan. The program has provided significant experience in the manufacture, acceptance testing, deployment, and support of on-site fuel cell systems. Initial field test results also show that these experimental power plants meet the performance and environmental requirements of a commercial specification. This Interim Report encompasses the design and manufacturing phases of the 40 kW Power Plant Manufacturing and Field Test program. The contract between UTC and NASA also provides UTC field engineering support to the host utilities, training programs and associated manuals for utility operating and maintenance personnel, spare parts support for a defined test period, and testing at UTC of a power plant made available from a preceding program phase. These activities are ongoing and will be reported subsequently.

  9. Microscale Fuel Cells

    SciTech Connect

    Holladay, Jamie D.; Viswanathan, Vish V.

    2005-11-03

    Perhaprs some of the most innovative work on fuel cells has been the research dedicated to applying silicon fabrication techniques to fuel cells technology creating low power microscale fuel cells applicable to microelectro mechanical systems (MEMS), microsensors, cell phones, PDA’s, and other low power (0.001 to 5 We) applications. In this small power range, fuel cells offer the decoupling of the energy converter from the energy storage which may enable longer operating times and instant or near instant charging. To date, most of the microscale fuel cells being developed have been based on proton exchange membrane fuel cell technology (PEMFC) or direct methanol fuel cell (DMFC) technology. This section will discuss requirements and considerations that need to be addressed in the development of microscale fuel cells, as well as some proposed designs and fabrication strategies.

  10. Solid Oxide Fuel Cell Technology Stationary Power Application Project

    SciTech Connect

    Joseph Pierre

    2009-03-05

    The objectives of this program were to: (1) Develop a reliable, cost-effective, and production-friendly technique to apply the power-enhancing layer at the interface of the air electrode and electrolyte of the Siemens SOFC; (2) Design, build, install, and operate in the field two 5 kWe SOFC systems fabricated with the state-of-the-art cylindrical, tubular cell and bundle technology and incorporating advanced module design features. Siemens successfully demonstrated, first in a number of single cell tests and subsequently in a 48-cell bundle test, a significant power enhancement by employing a power-enhancing composite interlayer at the interface between the air electrode and electrolyte. While successful from a cell power enhancement perspective, the interlayer application process was not suitable for mass manufacturing. The application process was of inconsistent quality, labor intensive, and did not have an acceptable yield. This program evaluated the technical feasibility of four interlayer application techniques. The candidate techniques were selected based on their potential to achieve the technical requirements of the interlayer, to minimize costs (both labor and material), and suitably for large-scale manufacturing. Preliminary screening, utilizing lessons learned in manufacturing tubular cells, narrowed the candidate processes to two, ink-roller coating (IRC) and dip coating (DC). Prototype fixtures were successfully built and utilized to further evaluate the two candidate processes for applying the interlayer to the high power density Delta8 cell geometry. The electrical performance of interlayer cells manufactured via the candidate processes was validated. Dip coating was eventually selected as the application technique of choice for applying the interlayer to the high power Delta8 cell. The technical readiness of the DC process and product quality was successfully and repeatedly demonstrated, and its throughput and cost are amenable to large scale

  11. A polymer electrolyte fuel cell stack for stationary power generation from hydrogen fuel

    SciTech Connect

    Gottesfeld, S.

    1995-09-01

    The fuel cell is the most efficient device for the conversion of hydrogen fuel to electric power. As such, the fuel cell represents a key element in efforts to demonstrate and implement hydrogen fuel utilization for electric power generation. The low temperature, polymer electrolyte membrane fuel cell (PEMFC) has recently been identified as an attractive option for stationary power generation, based on the relatively simple and benign materials employed, the zero-emission character of the device, and the expected high power density, high reliability and low cost. However, a PEMFC stack fueled by hydrogen with the combined properties of low cost, high performance and high reliability has not yet been demonstrated. Demonstration of such a stack will remove a significant barrier to implementation of this advanced technology for electric power generation from hydrogen. Work done in the past at LANL on the development of components and materials, particularly on advanced membrane/electrode assemblies (MEAs), has contributed significantly to the capability to demonstrate in the foreseeable future a PEMFC stack with the combined characteristics described above. A joint effort between LANL and an industrial stack manufacturer will result in the demonstration of such a fuel cell stack for stationary power generation. The stack could operate on hydrogen fuel derived from either natural gas or from renewable sources. The technical plan includes collaboration with a stack manufacturer (CRADA). It stresses the special requirements from a PEMFC in stationary power generation, particularly maximization of the energy conversion efficiency, extension of useful life to the 10 hours time scale and tolerance to impurities from the reforming of natural gas.

  12. Assessment and comparison of 100-MW coal gasification phosphoric acid fuel cell power plants

    NASA Technical Reports Server (NTRS)

    Lu, Cheng-Yi

    1988-01-01

    One of the advantages of fuel cell (FC) power plants is fuel versatility. With changes only in the fuel processor, the power plant will be able to accept a variety of fuels. This study was performed to design process diagrams, evaluate performance, and to estimate cost of 100 MW coal gasifier (CG)/phosphoric acid fuel cell (PAFC) power plant systems utilizing coal, which is the largest single potential source of alternate hydrocarbon liquids and gases in the United States, as the fuel. Results of this study will identify the most promising integrated CG/PAFC design and its near-optimal operating conditions. The comparison is based on the performance and cost of electricity which is calculated under consistent financial assumptions.

  13. MOLTEN CARBONATE FUEL CELL POWER PLANT LOCATED AT LADWP MAIN STREET SERVICE CENTER

    SciTech Connect

    William W. Glauz

    2004-09-10

    The Los Angeles Department of Water and Power (LADWP) has developed one of the most recognized fuel cell demonstration programs in the United States. In addition to their high efficiencies and superior environmental performance, fuel cells and other generating technologies that can be located at or near the load, offers several electric utility benefits. Fuel cells can help further reduce costs by reducing peak electricity demand, thereby deferring or avoiding expenses for additional electric utility infrastructure. By locating generators near the load, higher reliability of service is possible and the losses that occur during delivery of electricity from remote generators are avoided. The potential to use renewable and locally available fuels, such as landfill or sewage treatment waste gases, provides another attractive outlook. In Los Angeles, there are also many oil producing areas where the gas by-product can be utilized. In June 2000, the LADWP contracted with FCE to install and commission the precommercial 250kW MCFC power plant. The plant was delivered, installed, and began power production at the JFB in August 2001. The plant underwent manufacturer's field trials up for 18 months and was replace with a commercial plant in January 2003. In January 2001, the LADWP contracted with FCE to provide two additional 250kW MCFC power plants. These commercial plants began operations during mid-2003. The locations of these plants are at the Terminal Island Sewage Treatment Plant at the Los Angeles Harbor (for eventual operation on digester gas) and at the LADWP Main Street Service Center east of downtown Los Angeles. All three carbonate fuel cell plants received partial funding through the Department of Defense's Climate Change Fuel Cell Buydown Program. This report covers the technical evaluation and benefit-cost evaluation of the Main Street 250kW MCFC power plant during its first year of operation from September 2003 to August 2004. The data for the month of

  14. Research development and demonstration of a fuel cell/battery powered bus system. Annual report, January 1--December 31, 1994

    SciTech Connect

    Wimmer, R.

    1995-01-01

    This report describes the progress in the Georgetown University research, development and demonstration project of a fuel cell/battery powered bus system. The topics addressed in the report include demonstrations, vehicle design and application analysis, technology transfer activities, coordination and monitoring of system design and integration contractor, fuel cell bus test program, current problems, work planned, and manpower, cost and schedule reports.

  15. Landfill gas cleanup for carbonate fuel cell power generation. CRADA final report

    SciTech Connect

    Steinfeld, G.; Sanderson, R.

    1998-02-01

    The overall objective of the work reported here was to evaluate the extent to which conventional contaminant removal processes could be combined to economically reduce contaminant levels to the specifications for carbonate fuel cells. The technical effort was conducted by EPRI, consultant David Thimsen, Kaltec of Minnesota, Energy Research Corporation (ERC) and Interpoll Laboratories. The Electric Power Research Institute (EPRI) made available two test skids originally used to test an ERC 30 kW carbonate fuel cell at the Destec Coal Gasification Plan in Plaquemine, LA. EPRI`s carbonate fuel cell pilot plant was installed at the Anoka County Regional Landfill in Ramsey, Minnesota. Additional gas cleaning equipment was installed to evaluate a potentially inexpensive, multi-stage gas cleaning process to remove sulfur and chlorine in the gas to levels acceptable for long-term, economical carbonate fuel cell operation. The pilot plant cleaned approximately 970,000 scf (27,500 Nm{sup 3}) of gas over 1,000 hours of operation. The testing showed that the process could achieve the following polished gas concentrations. Less than 80 ppbv hydrogen sulfide; less than 1 ppmv (the detection limit) organic sulfur; less than 300 ppbv hydrogen chloride; less than 20--80 ppbv of any individual chlorined hydrocarbon; and 1.5 ppm sulfur dioxide. These were the detection limits of the analytical procedures employed. It is probable that the actual concentrations are below these analytical limits.

  16. Characterization and quantification of uncertainty in solid oxide fuel cell hybrid power plants

    NASA Astrophysics Data System (ADS)

    Subramanyan, Karthik; Diwekar, Urmila M.

    Distributed power generation is one of the most powerful applications of fuel cell technology. Several types of configurations have been hypothesized and tested for these kinds of applications at the conceptual level, but hybrid power plants are one of the most efficient. These are designs that combine the fuel cell cycle with other thermodynamic cycles to provide higher efficiency. The power plant in focus is the high pressure (HP)-low pressure (LP) solid oxide fuel cells (SOFC)/steam turbine (ST)/gas turbine (GT) configuration which is a part of the vision-21 program, which is a new approach, the U.S. Department of Energy's (DOE's) Office of Fossil Energy has begun, for developing 21st century energy plants that would have virtually no environmental impact. The overall goal is to effectively eliminate—at competitive costs—environmental concerns associated with the use of fossil fuels, for producing electricity and transportation fuels. In this design, coal is gasified in an entrained bed gasifier and the syn-gas produced is cleaned in a transport bed desulfurizer and passed over to cascaded SOFC modules (at two pressure levels). This module is integrated with a reheat GT cycle. The heat of the exhaust from the GT cycle is used to convert water to steam, which is eventually used in a steam bottoming cycle. Since this hybrid technology is new and futuristic, the system level models used for predicting the fuel cells' performance and for other modules like the desulfurizer have significant uncertainties in them. Also, the performance curves of the SOFC would differ depending on the materials used for the anode, cathode and electrolyte. The accurate characterization and quantification of these uncertainties is crucial for the validity of the model predictions and hence is the main focus of this paper. This work performs a two-level uncertainty analysis of the fuel cell module: uncertainty associated with (1) model and (2) material used for anode, cathode and

  17. Development of molten carbonate fuel cell power plant technology

    NASA Astrophysics Data System (ADS)

    Healy, H. C.; Sanderson, R. A.; Wertheim, F. J.; Farris, P. F.; Mientek, A. P.; Maricle, D. L.; Briggs, T. A.; Preston, J. L., Jr.; Louis, G. A.; Abrams, M. L.

    1980-08-01

    During this quarter, effort was continued in all four major task areas: system studies to define the reference power plant design; cell and stack design, development and verification; preparation for fabrication and testing of the full-scale prototype stack; and developing the capability for operation of stacks on coal-derived gas. Preliminary module and cell stack design requirements were completed. Fuel processor characterization was completed. Design approaches for full-scale stack busbars and electrical isolation of reactant manifolds and reactant piping were defined. Preliminary design requirements were completed for the anode. Conductive nickel oxide for cathode fabrication was made by oxidation and lithiation of porous nickel sheet stock. A method of mechanizing the tape casting process for increased production rates was successfully demonstrated. Theoretical calculations indicated that hydrogen cyanide and ammonia, when present as impurities in the stack fuel gas, will have no harmful effects. Laboratory experiments using higher than anticipated levels of ethylene showed no harmful effects.

  18. CLIMATE CHANGE FUEL CELL PROGRAM 200 kW - PC25C FUEL CELL POWER PLANT FOR THE ST.-AGNES-HOSPITAL, BOCHOLT, GERMANY

    SciTech Connect

    Dipl.-Ing. Knut Stahl

    2002-01-31

    Since the beginning of the Year 2001, the Saint-Agnes-Hospital in Bocholt, Germany, operates a phosphoric acid fuel cell (PAFC) to provide the base load of electrical power as well as heat in Winter and air conditioning in Summer. The project was made possible by federal funding from the U.S. Department of Energy as well as by a strategic alliance with the local utility company, the Bocholter Energie- und Wasserversorgung GmbH (BEW), and with the gas supplier of BEW, the Thyssengas GmbH. The fuel cell power plant is combined with an absorption chiller. It is highly efficient and has an excellent power to heat ratio. The operation during the first Year went smoothly and nearly free of trouble.

  19. Combined Power Generation and Carbon Sequestration Using Direct FuelCell

    SciTech Connect

    Hossein Ghezel-Ayagh

    2006-03-01

    The unique chemistry of carbonate fuel cell offers an innovative approach for separation of carbon dioxide from greenhouse gases (GHG). The carbonate fuel cell system also produces electric power at high efficiency. The simultaneous generation of power and sequestration of greenhouse gases offer an attractive scenario for re-powering the existing coal-fueled power plants, in which the carbonate fuel cell would separate the carbon dioxide from the flue gas and would generate additional pollutant-free electric power. Development of this system is concurrent with emergence of Direct FuelCell{reg_sign} (DFC{reg_sign}) technology for generation of electric power from fossil fuels. DFC is based on carbonate fuel cell featuring internal reforming. This technology has been deployed in MW-scale power plants and is readily available as a manufactured product. This final report describes the results of the conceptualization study conducted to assess the DFC-based system concept for separation of CO2 from GHG. Design and development studies were focused on integration of the DFC systems with coal-based power plants, which emit large amounts of GHG. In parallel to the system design and simulation activities, operation of laboratory scale DFC verified the technical concept and provided input to the design activity. The system was studied to determine its effectiveness in capturing more than ninety percent of CO2 from the flue gases. Cost analysis was performed to estimate the change in cost of electricity for a 200 MW pulverized coal boiler steam cycle plant retrofitted with the DFC-based CO2 separation system producing an additional 127 MW of electric power. The cost increments as percentage of levelized cost of electricity were estimated for a range of separation plant installations per year and a range of natural gas cost. The parametric envelope meeting the goal (<20% increase in COE) was identified. Results of this feasibility study indicated that DFC-based separation

  20. A methodology for the validated design space exploration of fuel cell powered unmanned aerial vehicles

    NASA Astrophysics Data System (ADS)

    Moffitt, Blake Almy

    Unmanned Aerial Vehicles (UAVs) are the most dynamic growth sector of the aerospace industry today. The need to provide persistent intelligence, surveillance, and reconnaissance for military operations is driving the planned acquisition of over 5,000 UAVs over the next five years. The most pressing need is for quiet, small UAVs with endurance beyond what is capable with advanced batteries or small internal combustion propulsion systems. Fuel cell systems demonstrate high efficiency, high specific energy, low noise, low temperature operation, modularity, and rapid refuelability making them a promising enabler of the small, quiet, and persistent UAVs that military planners are seeking. Despite the perceived benefits, the actual near-term performance of fuel cell powered UAVs is unknown. Until the auto industry began spending billions of dollars in research, fuel cell systems were too heavy for useful flight applications. However, the last decade has seen rapid development with fuel cell gravimetric and volumetric power density nearly doubling every 2--3 years. As a result, a few design studies and demonstrator aircraft have appeared, but overall the design methodology and vehicles are still in their infancy. The design of fuel cell aircraft poses many challenges. Fuel cells differ fundamentally from combustion based propulsion in how they generate power and interact with other aircraft subsystems. As a result, traditional multidisciplinary analysis (MDA) codes are inappropriate. Building new MDAs is difficult since fuel cells are rapidly changing in design, and various competitive architectures exist for balance of plant, hydrogen storage, and all electric aircraft subsystems. In addition, fuel cell design and performance data is closely protected which makes validation difficult and uncertainty significant. Finally, low specific power and high volumes compared to traditional combustion based propulsion result in more highly constrained design spaces that are

  1. Analysis and optimization of solid oxide fuel cell-based auxiliary power units using a generic zero-dimensional fuel cell model

    NASA Astrophysics Data System (ADS)

    Göll, S.; Samsun, R. C.; Peters, R.

    Fuel-cell-based auxiliary power units can help to reduce fuel consumption and emissions in transportation. For this application, the combination of solid oxide fuel cells (SOFCs) with upstream fuel processing by autothermal reforming (ATR) is seen as a highly favorable configuration. Notwithstanding the necessity to improve each single component, an optimized architecture of the fuel cell system as a whole must be achieved. To enable model-based analyses, a system-level approach is proposed in which the fuel cell system is modeled as a multi-stage thermo-chemical process using the "flowsheeting" environment PRO/II™. Therein, the SOFC stack and the ATR are characterized entirely by corresponding thermodynamic processes together with global performance parameters. The developed model is then used to achieve an optimal system layout by comparing different system architectures. A system with anode and cathode off-gas recycling was identified to have the highest electric system efficiency. Taking this system as a basis, the potential for further performance enhancement was evaluated by varying four parameters characterizing different system components. Using methods from the design and analysis of experiments, the effects of these parameters and of their interactions were quantified, leading to an overall optimized system with encouraging performance data.

  2. Advanced system analysis for indirect methanol fuel cell power plants for transportation applications

    NASA Astrophysics Data System (ADS)

    Vanderborgh, Nicholas E.; McFarland, Robert D.; Huff, James R.

    The indirect methanol cell fuel concept actively pursued by the USDOE and General Motors Corporation proposes the development of an electrochemical engine (e.c.e.), an electrical generator capable for usually efficient and clean power production from methanol fuel for the transportation sector. This on-board generator works in consort with batteries to provide electrical power to drive propulsion motors for a range of electric vehicles. Success in this technology could do much to improve impacted environmental areas and to convert part of the transportation fleet to natural gas and coal derived methanol as the fuel source. These developments parallel work in Europe and Japan where various fuel cell powered vehicles, often fueled with tanked or hydride hydrogen, are under active development. Transportation applications present design challenges that are distinctly different from utility requirements, the thrust of most of previous fuel cell programs. In both cases, high conversion efficiency (fuel to electricity) is essential. However, transportation requirements dictate as well designs for high power densities, rapid transients including short times for system start up, and consumer safety. The e.c.e. system is formed from four interacting components: (1) the fuel processor; (2) the fuel cell stack; (3) the air compression and decompression device; and (4) the condensing cross flow heat exchange device.

  3. The reasons for the high power density of fuel cells fabricated with directly deposited membranes

    NASA Astrophysics Data System (ADS)

    Vierrath, Severin; Breitwieser, Matthias; Klingele, Matthias; Britton, Benjamin; Holdcroft, Steven; Zengerle, Roland; Thiele, Simon

    2016-09-01

    In a previous study, we reported that polymer electrolyte fuel cells prepared by direct membrane deposition (DMD) produced power densities in excess of 4 W/cm2. In this study, the underlying origins that give rise to these high power densities are investigated and reported. The membranes of high power, DMD-fabricated fuel cells are relatively thin (12 μm) compared to typical benchmark, commercially available membranes. Electrochemical impedance spectroscopy, at high current densities (2.2 A/cm2) reveals that mass transport resistance was half that of reference, catalyst-coated-membranes (CCM). This is attributed to an improved oxygen supply in the cathode catalyst layer by way of a reduced propensity of flooding, and which is facilitated by an enhancement in the back diffusion of water from cathode to anode through the thin directly deposited membrane. DMD-fabricated membrane-electrode-assemblies possess 50% reduction in ionic resistance (15 mΩcm2) compared to conventional CCMs, with contributions of 9 mΩcm2 for the membrane resistance and 6 mΩcm2 for the contact resistance of the membrane and catalyst layer ionomer. The improved mass transport is responsible for 90% of the increase in power density of the DMD fuel cell, while the reduced ionic resistance accounts for a 10% of the improvement.

  4. High Efficiency Direct Carbon and Hydrogen Fuel Cells for Fossil Fuel Power Generation

    SciTech Connect

    Steinberg, M; Cooper, J F; Cherepy, N

    2002-01-02

    Hydrogen he1 cells have been under development for a number of years and are now nearing commercial applications. Direct carbon fuel cells, heretofore, have not reached practical stages of development because of problems in fuel reactivity and cell configuration. The carbon/air fuel cell reaction (C + O{sub 2} = CO{sub 2}) has the advantage of having a nearly zero entropy change. This allows a theoretical efficiency of 100 % at 700-800 C. The activities of the C fuel and CO{sub 2} product do not change during consumption of the fuel. Consequently, the EMF is invariant; this raises the possibility of 100% fuel utilization in a single pass. (In contrast, the high-temperature hydrogen fuel cell has a theoretical efficiency of and changes in fuel activity limit practical utilizations to 75-85%.) A direct carbon fuel cell is currently being developed that utilizes reactive carbon particulates wetted by a molten carbonate electrolyte. Pure COZ is evolved at the anode and oxygen from air is consumed at the cathode. Electrochemical data is reported here for the carbon/air cell utilizing carbons derived from he1 oil pyrolysis, purified coal, purified bio-char and petroleum coke. At 800 O C, a voltage efficiency of 80% was measured at power densities of 0.5-1 kW/m2. Carbon and hydrogen fuels may be produced simultaneously at lugh efficiency from: (1) natural gas, by thermal decomposition, (2) petroleum, by coking or pyrolysis of distillates, (3) coal, by sequential hydrogasification to methane and thermal pyrolysis of the methane, with recycle of the hydrogen, and (4) biomass, similarly by sequential hydrogenation and thermal pyrolysis. Fuel production data may be combined with direct C and H2 fuel cell operating data for power cycle estimates. Thermal to electric efficiencies indicate 80% HHV [85% LHV] for petroleum, 75.5% HHV [83.4% LHV] for natural gas and 68.3% HHV [70.8% LHV] for lignite coal. Possible benefits of integrated carbon and hydrogen fuel cell power

  5. Temperature and Humidity Sensor Powered by an Individual Microbial Fuel Cell in a Power Management System.

    PubMed

    Zheng, Qi; Xiong, Lei; Mo, Bing; Lu, Weihong; Kim, Suki; Wang, Zhenyu

    2015-01-01

    Microbial fuel cells (MFCs) are of increasing interest as bioelectrochemical systems for decomposing organic materials and converting chemical energy into electricity. The main challenge for this technology is that the low power and voltage of the devices restricts the use of MFCs in practical applications. In this paper, a power management system (PMS) is developed to store the energy and export an increased voltage. The designed PMS successfully increases the low voltage generated by an individual MFC to a high potential of 5 V, capable of driving a wireless temperature and humidity sensor based on nRF24L01 data transmission modules. With the PMS, MFCs can intermittently power the sensor for data transmission to a remote receiver. It is concluded that even an individual MFC can supply the energy required to power the sensor and telemetry system with the designed PMS. The presented PMS can be widely used for unmanned environmental monitoring such as wild rivers, lakes, and adjacent water areas, and offers promise for further advances in MFC technology. PMID:26378546

  6. Temperature and Humidity Sensor Powered by an Individual Microbial Fuel Cell in a Power Management System

    PubMed Central

    Zheng, Qi; Xiong, Lei; Mo, Bing; Lu, Weihong; Kim, Suki; Wang, Zhenyu

    2015-01-01

    Microbial fuel cells (MFCs) are of increasing interest as bioelectrochemical systems for decomposing organic materials and converting chemical energy into electricity. The main challenge for this technology is that the low power and voltage of the devices restricts the use of MFCs in practical applications. In this paper, a power management system (PMS) is developed to store the energy and export an increased voltage. The designed PMS successfully increases the low voltage generated by an individual MFC to a high potential of 5 V, capable of driving a wireless temperature and humidity sensor based on nRF24L01 data transmission modules. With the PMS, MFCs can intermittently power the sensor for data transmission to a remote receiver. It is concluded that even an individual MFC can supply the energy required to power the sensor and telemetry system with the designed PMS. The presented PMS can be widely used for unmanned environmental monitoring such as wild rivers, lakes, and adjacent water areas, and offers promise for further advances in MFC technology. PMID:26378546

  7. The power of glove: Soft microbial fuel cell for low-power electronics

    NASA Astrophysics Data System (ADS)

    Winfield, Jonathan; Chambers, Lily D.; Stinchcombe, Andrew; Rossiter, Jonathan; Ieropoulos, Ioannis

    2014-03-01

    A novel, soft microbial fuel cell (MFC) has been constructed using the finger-piece of a standard laboratory natural rubber latex glove. The natural rubber serves as structural and proton exchange material whilst untreated carbon veil is used for the anode. A soft, conductive, synthetic latex cathode is developed that coats the outside of the glove. This inexpensive, lightweight reactor can without any external power supply, start up and energise a power management system (PMS), which steps-up the MFC output (0.06-0.17 V) to practical levels for operating electronic devices (>3 V). The MFC is able to operate for up to 4 days on just 2 mL of feedstock (synthetic tryptone yeast extract) without any cathode hydration. The MFC responds immediately to changes in fuel-type when the introduction of urine accelerates the cycling times (35 vs. 50 min for charge/discharge) of the MFC and PMS. Following starvation periods of up to 60 h at 0 mV the MFC is able to cold start the PMS simply with the addition of 2 mL fresh feedstock. These findings demonstrate that cheap MFCs can be developed as sole power sources and in conjunction with advancements in ultra-low power electronics, can practically operate small electrical devices.

  8. Fuel cell systems for auxiliary, main propulsion power: Planar solid-oxide and polymer-electrolyte systems yield stealth, endurance, reduced costs & emissions

    SciTech Connect

    Scoles, S.W.; Sapyta, J.J.

    1995-07-01

    The US Navy has identified fuel-cell systems as having significant promise for meeting the power needs of future generations of ships. A resently released report from the Carderock Division of the Naval Surface Warfare Center entitled, The Assessment of Fuel Cell Power Plants for Surface Combatants, compares various fuel-cell technologies with conventional shipboard power sources on the basis of the fuel-cell system`s influence in the design, cost, and effectiveness of surface combatants. Fuel-cell technologies have been available for many years but only recently have any of the five major types of fuel cells emerged from the R&D environments in a form usable in shipboard applications. The Carderock report identified planar solid-oxide fuel cells (PSOFC) and polymer-electrolyte fuel cells (PEFC) as the only fuel-cell technologies with the potential to provide combatants in all applications. This article examines each type and provides a technical and economic analysis.

  9. Fuzzy Logic Based Controller for a Grid-Connected Solid Oxide Fuel Cell Power Plant.

    PubMed

    Chatterjee, Kalyan; Shankar, Ravi; Kumar, Amit

    2014-10-01

    This paper describes a mathematical model of a solid oxide fuel cell (SOFC) power plant integrated in a multimachine power system. The utilization factor of a fuel stack maintains steady state by tuning the fuel valve in the fuel processor at a rate proportional to a current drawn from the fuel stack. A suitable fuzzy logic control is used for the overall system, its objective being controlling the current drawn by the power conditioning unit and meet a desirable output power demand. The proposed control scheme is verified through computer simulations. PMID:25053926

  10. Fuel processor for fuel cell power system. [Conversion of methanol into hydrogen

    DOEpatents

    Vanderborgh, N.E.; Springer, T.E.; Huff, J.R.

    1986-01-28

    A catalytic organic fuel processing apparatus, which can be used in a fuel cell power system, contains within a housing a catalyst chamber, a variable speed fan, and a combustion chamber. Vaporized organic fuel is circulated by the fan past the combustion chamber with which it is in indirect heat exchange relationship. The heated vaporized organic fuel enters a catalyst bed where it is converted into a desired product such as hydrogen needed to power the fuel cell. During periods of high demand, air is injected upstream of the combustion chamber and organic fuel injection means to burn with some of the organic fuel on the outside of the combustion chamber, and thus be in direct heat exchange relation with the organic fuel going into the catalyst bed.

  11. Techno-economic analysis of fuel cell auxiliary power units as alternative to idling

    NASA Astrophysics Data System (ADS)

    Jain, Semant; Chen, Hsieh-Yeh; Schwank, Johannes

    This paper presents a techno-economic analysis of fuel-cell-based auxiliary power units (APUs), with emphasis on applications in the trucking industry and the military. The APU system is intended to reduce the need for discretionary idling of diesel engines or gas turbines. The analysis considers the options for on-board fuel processing of diesel and compares the two leading fuel cell contenders for automotive APU applications: proton exchange membrane fuel cell and solid oxide fuel cell. As options for on-board diesel reforming, partial oxidation and auto-thermal reforming are considered. Finally, using estimated and projected efficiency data, fuel consumption patterns, capital investment, and operating costs of fuel-cell APUs, an economic evaluation of diesel-based APUs is presented, with emphasis on break-even periods as a function of fuel cost, investment cost, idling time, and idling efficiency. The analysis shows that within the range of parameters studied, there are many conditions where deployment of an SOFC-based APU is economically viable. Our analysis indicates that at an APU system cost of 100 kW -1, the economic break-even period is within 1 year for almost the entire range of conditions. At 500 kW -1 investment cost, a 2-year break-even period is possible except for the lowest end of the fuel consumption range considered. However, if the APU investment cost is 3000 kW -1, break-even would only be possible at the highest fuel consumption scenarios. For Abram tanks, even at typical land delivered fuel costs, a 2-year break-even period is possible for APU investment costs as high as 1100 kW -1.

  12. Technology development goals for automotive fuel cell power systems. Final report

    SciTech Connect

    James, B.D.; Baum, G.N.; Kuhn, I.F. Jr.

    1994-08-01

    This report determines cost and performance requirements for Proton Exchange Membrane (PEM) fuel cell vehicles carrying pure H{sub 2} fuel, to achieve parity with internal combustion engine (ICE) vehicles. A conceptual design of a near term FCEV (fuel cell electric vehicle) is presented. Complete power system weight and cost breakdowns are presented for baseline design. Near term FCEV power system weight is 6% higher than ICE system, mid-term FCEV projected weights are 29% lower than ICE`s. There are no inherently high-cost components in FCE, and at automotive production volumes, near term FCEV cost viability is closer at hand than at first thought. PEM current vs voltage performance is presented for leading PEM manufacturers and researchers. 5 current and proposed onboard hydrogen storage techniques are critically compared: pressurized gas, cryogenic liquid, combined pressurized/cryogenic, rechargeable hydride, adsorption. Battery, capacitor, and motor/controller performance is summarized. Fuel cell power system component weight and cost densities (threshold and goal) are tabulated.

  13. A synergetic use of hydrogen and fuel cells in human spaceflight power systems

    NASA Astrophysics Data System (ADS)

    Belz, S.

    2016-04-01

    Hydrogen is very flexible in different fields of application of energy conversion. It can be generated by water electrolysis. Stored in tanks it is available for re-electrification by fuel cells. But it is not only the power system, which benefits from use of hydrogen, but also the life support system, which can contain hydrogen consuming technologies for recycling management (e.g. carbon dioxide removal and waste combustion processes). This paper points out various fields of hydrogen use in a human spaceflight system. Depending on mission scenarios, shadow phases, and the need of energy storage, regenerative fuel cell systems can be more efficient than secondary batteries. Here, different power storage concepts are compared by equivalent system mass calculation, thus including impact in the peripheral structure (volume, thermal management, etc.) on the space system. It is also focused on the technical integration aspect, e.g. which peripheral components have to be adapted when hydrogen is also used for life support technologies and what system mass benefit can be expected. Finally, a recommendation is given for the following development steps for a synergetic use of hydrogen and fuel cells in human spaceflight power systems.

  14. Iron-based cathode catalyst with enhanced power density in polymer electrolyte membrane fuel cells.

    PubMed

    Proietti, Eric; Jaouen, Frédéric; Lefèvre, Michel; Larouche, Nicholas; Tian, Juan; Herranz, Juan; Dodelet, Jean-Pol

    2011-01-01

    H(2)-air polymer-electrolyte-membrane fuel cells are electrochemical power generators with potential vehicle propulsion applications. To help reduce their cost and encourage widespread use, research has focused on replacing the expensive Pt-based electrocatalysts in polymer-electrolyte-membrane fuel cells with a lower-cost alternative. Fe-based cathode catalysts are promising contenders, but their power density has been low compared with Pt-based cathodes, largely due to poor mass-transport properties. Here we report an iron-acetate/phenanthroline/zeolitic-imidazolate-framework-derived electrocatalyst with increased volumetric activity and enhanced mass-transport properties. The zeolitic-imidazolate-framework serves as a microporous host for phenanthroline and ferrous acetate to form a catalyst precursor that is subsequently heat treated. A cathode made with the best electrocatalyst from this work, tested in H(2)-O(2,) has a power density of 0.75 W cm(-2) at 0.6 V, a meaningful voltage for polymer-electrolyte-membrane fuel cells operation, comparable with that of a commercial Pt-based cathode tested under identical conditions. PMID:21811245

  15. Drinking water purification by electrosynthesis of hydrogen peroxide in a power-producing PEM fuel cell.

    PubMed

    Li, Winton; Bonakdarpour, Arman; Gyenge, Előd; Wilkinson, David P

    2013-11-01

    The industrial anthraquinone auto-oxidation process produces most of the world's supply of hydrogen peroxide. For applications that require small amounts of H2 O2 or have economically difficult transportation means, an alternate, on-site H2 O2 production method is needed. Advanced drinking water purification technologies use neutral-pH H2 O2 in combination with UV treatment to reach the desired water purity targets. To produce neutral H2 O2 on-site and on-demand for drinking water purification, the electroreduction of oxygen at the cathode of a proton exchange membrane (PEM) fuel cell operated in either electrolysis (power consuming) or fuel cell (power generating) mode could be a possible solution. The work presented here focuses on the H2 /O2 fuel cell mode to produce H2 O2 . The fuel cell reactor is operated with a continuous flow of carrier water through the cathode to remove the product H2 O2 . The impact of the cobalt-carbon composite cathode catalyst loading, Teflon content in the cathode gas diffusion layer, and cathode carrier water flowrate on the production of H2 O2 are examined. H2 O2 production rates of up to 200 μmol h(-1)  cmgeometric (-2) are achieved using a continuous flow of carrier water operating at 30 % current efficiency. Operation times of more than 24 h have shown consistent H2 O2 and power production, with no degradation of the cobalt catalyst. PMID:24039111

  16. An experimental study of a PEM fuel cell power train for urban bus application

    NASA Astrophysics Data System (ADS)

    Corbo, P.; Migliardini, F.; Veneri, O.

    An experimental study was carried out on a fuel cell propulsion system for minibus application with the aim to investigate the main issues of energy management within the system in dynamic conditions. The fuel cell system (FCS), based on a 20 kW PEM stack, was integrated into the power train comprising DC-DC converter, Pb batteries as energy storage systems and asynchronous electric drive of 30 kW. As reference vehicle a minibus for public transportation in historical centres was adopted. A preliminary experimental analysis was conducted on the FCS connected to a resistive load through a DC-DC converter, in order to verify the stack dynamic performance varying its power acceleration from 0.5 kW s -1 to about 4 kW s -1. The experiments on the power train were conducted on a test bench able to simulate the vehicle parameters and road characteristics on specific driving cycles, in particular the European R40 cycle was adopted as reference. The "soft hybrid" configuration, which permitted the utilization of a minimum size energy storage system and implied the use of FCS mainly in dynamic operation, was compared with the "hard hybrid" solution, characterized by FCS operation at limited power in stationary conditions. Different control strategies of power flows between fuel cells, electric energy storage system and electric drive were adopted in order to verify the two above hybrid approaches during the vehicle mission, in terms of efficiencies of individual components and of the overall power train. The FCS was able to support the dynamic requirements typical of R40 cycle, but an increase of air flow rate during the fastest acceleration phases was necessary, with only a slight reduction of FCS efficiency. The FCS efficiency resulted comprised between 45 and 48%, while the overall power train efficiency reached 30% in conditions of constant stack power during the driving cycle.

  17. A polymer electrolyte fuel cell stack for stationary power generation from hydrogen fuel

    SciTech Connect

    Wilson, M.S.; Moeller-Holst, S.; Webb, D.M.; Zawodzinski, C.; Gottesfeld, S.

    1998-08-01

    The objective is to develop and demonstrate a 4 kW, hydrogen-fueled polymer electrolyte fuel cell (PEFC) stack, based on non-machined stainless steel hardware and on membrane/electrode assemblies (MEAs) of low catalyst loadings. The stack is designed to operate at ambient pressure on the air-side and can accommodate operation at higher fuel pressures, if so required. This is to be accomplished by working jointly with a fuel cell stack manufacturer, based on a CRADA. The performance goals are 57% energy conversion efficiency hydrogen-to-electricity (DC) at a power density of 0.9 kW/liter for a stack operating at ambient inlet pressures. The cost goal is $600/kW, based on present materials costs.

  18. Fuel Cell Auxiliary Power Study Volume 1: RASER Task Order 5

    NASA Technical Reports Server (NTRS)

    Mak, Audie; Meier, John

    2007-01-01

    This study evaluated the feasibility of a hybrid solid oxide fuel cell (SOFC) auxiliary power unit (APU) and the impact in a 90-passenger More-Electric Regional Jet application. The study established realistic hybrid SOFC APU system weight and system efficiencies, and evaluated the impact on the aircraft total weight, fuel burn, and emissions from the main engine and the APU during cruise, landing and take-off (LTO) cycle, and at the gate. Although the SOFC APU may be heavier than the current conventional APU, its weight disadvantage can be offset by fuel savings in the higher SOFC APU system efficiencies against the main engine bleed and extraction during cruise. The higher SOFC APU system efficiency compared to the conventional APU on the ground can also provide considerable fuel saving and emissions reduction, particularly at the gate, but is limited by the fuel cell stack thermal fatigue characteristic.

  19. Characterization of a microfluidic microbial fuel cell as a power generator based on a nickel electrode.

    PubMed

    Mardanpour, Mohammad Mahdi; Yaghmaei, Soheila

    2016-05-15

    This study reports the fabrication of a microfluidic microbial fuel cell (MFC) using nickel as a novel alternative for conventional electrodes and a non-phatogenic strain of Escherichia coli as the biocatalyst. The feasibility of a microfluidic MFC as an efficient power generator for production of bioelectricity from glucose and urea as organic substrates in human blood and urine for implantable medical devices (IMDs) was investigated. A maximum open circuit potential of 459 mV was achieved for the batch-fed microfluidic MFC. During continuous mode operation, a maximum power density of 104 Wm(-3) was obtained with nutrient broth. For the glucose-fed microfluidic MFC, the maximum power density of 5.2 μW cm(-2) obtained in this study is significantly greater than the power densities reported previously for microsized MFCs and glucose fuel cells. The maximum power density of 14 Wm(-3) obtained using urea indicates the successful performance of a microfluidic MFC using human excreta. It features high power density, self-regeneration, waste management and a low production cost (<$1), which suggest it as a promising alternative to conventional power supplies for IMDs. The performance of the microfluidic MFC as a power supply was characterized based on polarization behavior and cell potential in different substrates, operational modes, and concentrations. PMID:26720922

  20. A Terrestrial Microbial Fuel Cell for Powering a Single-Hop Wireless Sensor Network

    PubMed Central

    Zhang, Daxing; Zhu, Yingmin; Pedrycz, Witold; Guo, Yongxian

    2016-01-01

    Microbial fuel cells (MFCs) are envisioned as one of the most promising alternative renewable energy sources because they can generate electric current continuously while treating waste. Terrestrial Microbial Fuel Cells (TMFCs) can be inoculated and work on the use of soil, which further extends the application areas of MFCs. Energy supply, as a primary influential factor determining the lifetime of Wireless Sensor Network (WSN) nodes, remains an open challenge in sensor networks. In theory, sensor nodes powered by MFCs have an eternal life. However, low power density and high internal resistance of MFCs are two pronounced problems in their operation. A single-hop WSN powered by a TMFC experimental setup was designed and experimented with. Power generation performance of the proposed TMFC, the relationships between the performance of the power generation and the environment temperature, the water content of the soil by weight were measured by experiments. Results show that the TMFC can achieve good power generation performance under special environmental conditions. Furthermore, the experiments with sensor data acquisition and wireless transmission of the TMFC powering WSN were carried out. We demonstrate that the obtained experimental results validate the feasibility of TMFCs powering WSNs. PMID:27213346

  1. A Terrestrial Microbial Fuel Cell for Powering a Single-Hop Wireless Sensor Network.

    PubMed

    Zhang, Daxing; Zhu, Yingmin; Pedrycz, Witold; Guo, Yongxian

    2016-01-01

    Microbial fuel cells (MFCs) are envisioned as one of the most promising alternative renewable energy sources because they can generate electric current continuously while treating waste. Terrestrial Microbial Fuel Cells (TMFCs) can be inoculated and work on the use of soil, which further extends the application areas of MFCs. Energy supply, as a primary influential factor determining the lifetime of Wireless Sensor Network (WSN) nodes, remains an open challenge in sensor networks. In theory, sensor nodes powered by MFCs have an eternal life. However, low power density and high internal resistance of MFCs are two pronounced problems in their operation. A single-hop WSN powered by a TMFC experimental setup was designed and experimented with. Power generation performance of the proposed TMFC, the relationships between the performance of the power generation and the environment temperature, the water content of the soil by weight were measured by experiments. Results show that the TMFC can achieve good power generation performance under special environmental conditions. Furthermore, the experiments with sensor data acquisition and wireless transmission of the TMFC powering WSN were carried out. We demonstrate that the obtained experimental results validate the feasibility of TMFCs powering WSNs. PMID:27213346

  2. Hydrogen Fuel Cell Analysis: Lessons Learned from Stationary Power Generation Final Report

    SciTech Connect

    Scott E. Grasman; John W. Sheffield; Fatih Dogan; Sunggyu Lee; Umit O. Koylu; Angie Rolufs

    2010-04-30

    This study considered opportunities for hydrogen in stationary applications in order to make recommendations related to RD&D strategies that incorporate lessons learned and best practices from relevant national and international stationary power efforts, as well as cost and environmental modeling of pathways. The study analyzed the different strategies utilized in power generation systems and identified the different challenges and opportunities for producing and using hydrogen as an energy carrier. Specific objectives included both a synopsis/critical analysis of lessons learned from previous stationary power programs and recommendations for a strategy for hydrogen infrastructure deployment. This strategy incorporates all hydrogen pathways and a combination of distributed power generating stations, and provides an overview of stationary power markets, benefits of hydrogen-based stationary power systems, and competitive and technological challenges. The motivation for this project was to identify the lessons learned from prior stationary power programs, including the most significant obstacles, how these obstacles have been approached, outcomes of the programs, and how this information can be used by the Hydrogen, Fuel Cells & Infrastructure Technologies Program to meet program objectives primarily related to hydrogen pathway technologies (production, storage, and delivery) and implementation of fuel cell technologies for distributed stationary power. In addition, the lessons learned address environmental and safety concerns, including codes and standards, and education of key stakeholders.

  3. Generating power from cellulose in an alkaline fuel cell enhanced by methyl viologen as an electron-transfer catalyst

    NASA Astrophysics Data System (ADS)

    Hao, Miaoqing; Liu, Xianhua; Feng, Mengnan; Zhang, Pingping; Wang, Guangyi

    2014-04-01

    In this work, we developed a single-compartment direct cellulose alkaline fuel cell by using nickel foam as the anode and methyl viologen as an electron transfer catalyst. The maximum power density of the fuel cell at optimal conditions is 450 mW m-2. High-performance liquid chromatography detected short-chain aliphatic carboxylic acids in the oxidation products. Using common reed and red algae as fuels, the fuel cell achieved maximum power densities of 295 mW m-2 and 154 mW m-2, respectively.

  4. American Recovery & Reinvestment Act: Fuel Cell Hybrid Power Packs and Hydrogen Refueling for Lift Trucks

    SciTech Connect

    Block, Gus

    2011-07-31

    HEB Grocery Company, Inc. (H-E-B) is a privately-held supermarket chain with 310 stores throughout Texas and northern Mexico. H-E-B converted 14 of its lift reach trucks to fuel cell power using Nuvera Fuel Cells’ PowerEdge™ units to verify the value proposition and environmental benefits associated with the technology. Issues associated with the increasing power requirements of the distribution center operation, along with high ambient temperature in the summer and other operating conditions (such as air quality and floor surface condition), surfaced opportunities for improving Nuvera’s PowerEdge fuel cell system design in high-throughput forklift environments. The project included on-site generation of hydrogen from a steam methane reformer, called PowerTap™ manufactured by Nuvera. The hydrogen was generated, compressed and stored in equipment located outside H-E-B’s facility, and provided to the forklifts by hydrogen dispensers located in high forklift traffic areas. The PowerEdge fuel cell units logged over 25,300 operating hours over the course of the two-year project period. The PowerTap hydrogen generator produced more than 11,100 kg of hydrogen over the same period. Hydrogen availability at the pump was 99.9%. H-E-B management has determined that fuel cell forklifts help alleviate several issues in its distribution centers, including truck operator downtime associated with battery changing, truck and battery maintenance costs, and reduction of grid electricity usage. Data collected from this initial installation demonstrated a 10% productivity improvement, which enabled H-E-B to make economic decisions on expanding the fleet of PowerEdge and PowerTap units in the fleet, which it plans to undertake upon successful demonstration of the new PowerEdge reach truck product. H-E-B has also expressed interst in other uses of hydrogen produced on site in the future, such as for APUs used in tractor trailers and refrigerated transport trucks in its fleet.

  5. Current status of fuel cell based combined heat and power systems for residential sector

    NASA Astrophysics Data System (ADS)

    Ellamla, Harikishan R.; Staffell, Iain; Bujlo, Piotr; Pollet, Bruno G.; Pasupathi, Sivakumar

    2015-10-01

    Combined Heat and Power (CHP) is the sequential or simultaneous generation of multiple forms of useful energy, usually electrical and thermal, in a single and integrated system. Implementing CHP systems in the current energy sector may solve energy shortages, climate change and energy conservation issues. This review paper is divided into six sections: the first part defines and classifies the types of fuel cell used in CHP systems; the second part discusses the current status of fuel cell CHP (FC-CHP) around the world and highlights the benefits and drawbacks of CHP systems; the third part focuses on techniques for modelling CHP systems. The fourth section gives a thorough comparison and discussion of the two main fuel cell technologies used in FC-CHP (PEMFC and SOFC), characterising their technical performance and recent developments from the major manufacturers. The fifth section describes all the main components of FC-CHP systems and explains the issues connected with their practical application. The last part summarises the above, and reflects on micro FC-CHP system technology and its future prospects.

  6. Power sources for portable electronics and hybrid cars: lithium batteries and fuel cells.

    PubMed

    Scrosati, Bruno

    2005-01-01

    The activities in progress in our laboratory for the development of batteries and fuel cells for portable electronics and hybrid car applications are reviewed and discussed. In the case of lithium batteries, the research has been mainly focused on the characterization of new electrode and electrolyte materials. Results related to disordered carbon anodes and improved, solvent-free, as well as gel-type, polymer electrolytes are particularly stressed. It is shown that the use of proper gel electrolytes, in combination with suitable electrode couples, allows the development of new types of safe, reliable, and low-cost lithium ion batteries which appear to be very promising power sources for hybrid vehicles. Some of the technologies proven to be successful in the lithium battery area are readapted for use in fuel cells. In particular, this approach has been followed for the preparation of low-cost and stable protonic membranes to be proposed as an alternative to the expensive, perfluorosulfonic membranes presently used in polymer electrolyte membrane fuel cells (PEMFCs). PMID:16211622

  7. Combined solid oxide fuel cell and gas turbine systems for efficient power and heat generation

    NASA Astrophysics Data System (ADS)

    Palsson, Jens; Selimovic, Azra; Sjunnesson, Lars

    The Department of Heat and Power Engineering at Lund University in Sweden has been conducting theoretical studies of combined SOFC and gas turbine (SOFC/GT) cycles. The overall goal is an unbiased evaluation of performance prospects and operational behaviour of such systems. The project is part of a Swedish national program on high-temperature fuel cells. Results of continuous studies started earlier by authors are presented. Recent developments in modelling techniques has resulted in a more accurate fuel cell model giving an advantage over previous system studies based on simplified SOFC models. The fuel cell model has been improved by detailed representation of resistive cell losses, reaction kinetics for the reforming reaction and heat conduction through the solid part of the cell. This SOFC model has further been confirmed against the literature and integrated into simulation software, Aspen Plus™. Recent calculations have focused on a system with external pre-reforming and anode gas recirculation for the internal supply of steam. A reference system, sized at 500 kW, has also been analyzed in variants with gas turbine reheat and air compression intercooling. In addition, knowledge of stack and system behaviour has been gained from sensitivity studies. It is shown that the pressure ratio has a large impact on performance and that electrical efficiencies of more than 65% are possible at low pressure ratios.

  8. Fuel Cell Power Plant Initiative. Volume 1; Solid Oxide Fuel Cell/Logistics Fuel Processor 27 kWe Power System Demonstration for ARPA

    NASA Technical Reports Server (NTRS)

    Veyo, S.E.

    1997-01-01

    This report describes the successful testing of a 27 kWe Solid Oxide Fuel Cell (SOFC) generator fueled by natural gas and/or a fuel gas produced by a brassboard logistics fuel preprocessor (LFP). The test period began on May 24, 1995 and ended on February 26, 1996 with the successful completion of all program requirements and objectives. During this time period, this power system produced 118.2 MWh of electric power. No degradation of the generator's performance was measured after 5582 accumulated hours of operation on these fuels: local natural gas - 3261 hours, jet fuel reformate gas - 766 hours, and diesel fuel reformate gas - 1555 hours. This SOFC generator was thermally cycled from full operating temperature to room temperature and back to operating temperature six times, because of failures of support system components and the occasional loss of test site power, without measurable cell degradation. Numerous outages of the LFP did not interrupt the generator's operation because the fuel control system quickly switched to local natural gas when an alarm indicated that the LFP reformate fuel supply had been interrupted. The report presents the measured electrical performance of the generator on all three fuel types and notes the small differences due to fuel type. Operational difficulties due to component failures are well documented even though they did not affect the overall excellent performance of this SOFC power generator. The final two appendices describe in detail the LFP design and the operating history of the tested brassboard LFP.

  9. Fuel Cell Power Plant Initiative. Volume 2; Preliminary Design of a Fixed-Base LFP/SOFC Power System

    NASA Technical Reports Server (NTRS)

    Veyo, S.E.

    1997-01-01

    This report documents the preliminary design for a military fixed-base power system of 3 MWe nominal capacity using Westinghouse's tubular Solid Oxide Fuel Cell [SOFC] and Haldor Topsoe's logistic fuels processor [LFP]. The LFP provides to the fuel cell a methane rich sulfur free fuel stream derived from either DF-2 diesel fuel, or JP-8 turbine fuel. Fuel cells are electrochemical devices that directly convert the chemical energy contained in fuels such as hydrogen, natural gas, or coal gas into electricity at high efficiency with no intermediate heat engine or dynamo. The SOFC is distinguished from other fuel cell types by its solid state ceramic structure and its high operating temperature, nominally 1000'C. The SOFC pioneered by Westinghouse has a tubular geometry closed at one end. A power generation stack is formed by aggregating many cells in an ordered array. The Westinghouse stack design is distinguished from other fuel cell stacks by the complete absence of high integrity seals between cell elements, cells, and between stack and manifolds. Further, the reformer for natural gas [predominantly methane] and the stack are thermally and hydraulically integrated with no requirement for process water. The technical viability of combining the tubular SOFC and a logistic fuels processor was demonstrated at 27 kWe scale in a test program sponsored by the Advanced Research Projects Agency [ARPA) and carried out at the Southern California Edison's [SCE] Highgrove generating station near San Bernardino, California in 1994/95. The LFP was a breadboard design supplied by Haldor Topsoe, Inc. under subcontract to Westinghouse. The test program was completely successful. The LFP fueled the SOFC for 766 hours on JP-8 and 1555 hours of DF-2. In addition, the fuel cell operated for 3261 hours on pipeline natural gas. Over the 5582 hours of operation, the SOFC generated 118 MVVH of electricity with no perceptible degradation in performance. The LFP processed military

  10. Prediction-based optimal power management in a fuel cell/battery plug-in hybrid vehicle

    NASA Astrophysics Data System (ADS)

    Bubna, Piyush; Brunner, Doug; Advani, Suresh G.; Prasad, Ajay K.

    A prediction-based power management strategy is proposed for fuel cell/battery plug-in hybrid vehicles with the goal of improving overall system operating efficiency. The main feature of the proposed strategy is that, if the total amount of energy required to complete a particular drive cycle can be reliably predicted, then the energy stored in the onboard electrical storage system can be depleted in an optimal manner that permits the fuel cell to operate in its most efficient regime. The strategy has been implemented in a vehicle power-train simulator called LFM which was developed in MATLAB/SIMULINK software and its effectiveness was evaluated by comparing it with a conventional control strategy. The proposed strategy is shown to provide significant improvement in average fuel cell system efficiency while reducing hydrogen consumption. It has been demonstrated with the LFM simulation that the prediction-based power management strategy can maintain a stable power request to the fuel cell thereby improving fuel cell durability, and that the battery is depleted to the desired state-of-charge at the end of the drive cycle. A sensitivity analysis has also been conducted to study the effects of inaccurate predictions of the remaining portion of the drive cycle on hydrogen consumption and the final battery state-of-charge. Finally, the advantages of the proposed control strategy over the conventional strategy have been validated through implementation in the University of Delaware's fuel cell hybrid bus with operational data acquired from onboard sensors.

  11. Design of a mediated enzymatic fuel cell to generate power from renewable fuel sources.

    PubMed

    Korkut, Seyda; Kilic, Muhammet Samet

    2016-01-01

    The present work reported a compartment-less enzymatic fuel cell (EFC) based on newly synthesized Poly(pyrrole-2-carboxylic acid-co-3-thiophene acetic acid) film containing glucose oxidase and laccase effectively wired by p-benzoquinone incorporated into the copolymer structure. The resulting system generated a power density of 18.8 µW/cm(2) with 30 mM of glucose addition at +0.94 V at room temperature. Improvements to maximize the power output were ensured with step-by-step optimization of electrode fabrication design and operational parameters for operating the system with renewable fuel sources. We demonstrated that the improved fuel cell could easily harvest glucose produced during photosynthesis to produce electrical energy in a simple, renewable and sustainable way by generating a power density of 10 nW/cm(2) in the plant leaf within 2 min. An EFC for the first time was successfully operated in municipal wastewater which contained glycolytic substances to generate electrical energy with a power output of 3.3 µW/cm(2). PMID:26102352

  12. Intermediate-sized natural gas fueled carbonate fuel cell power plants

    NASA Astrophysics Data System (ADS)

    Sudhoff, Frederick A.; Fleming, Donald K.

    1994-04-01

    This executive summary of the report describes the accomplishments of the joint US Department of Energy's (DOE) Morgantown Energy Technology Center (METC) and M-C POWER Corporation's Cooperative Research and Development Agreement (CRADA) No. 93-013. This study addresses the intermediate power plant size between 2 megawatt (MW) and 200 MW. A 25 MW natural-gas, fueled-carbonate fuel cell power plant was chosen for this purpose. In keeping with recent designs, the fuel cell will operate under approximately three atmospheres of pressure. An expander/alternator is utilized to expand exhaust gas to atmospheric conditions and generate additional power. A steam-bottoming cycle is not included in this study because it is not believed to be cost effective for this system size. This study also addresses the simplicity and accuracy of a spreadsheet-based simulation with that of a full Advanced System for Process Engineering (ASPEN) simulation. The personal computer can fully utilize the simple spreadsheet model simulation. This model can be made available to all users and is particularly advantageous to the small business user.

  13. NASA's PEM Fuel Cell Power Plant Development Program for Space Applications

    NASA Technical Reports Server (NTRS)

    Hoberecht, Mark

    2006-01-01

    NASA embarked on a PEM fuel cell power plant development program beginning in 2001. This five-year program was conducted by a three-center NASA team of Glenn Research Center (lead), Johnson Space Center, and Kennedy Space Center. The program initially was aimed at developing hardware for a Reusable Launch Vehicle (RLV) application, but more recently had shifted to applications supporting the NASA Exploration Program. The first phase of the development effort, to develop breadboard hardware in the 1-5 kW power range, was conducted by two competing vendors. The second phase of the effort, to develop Engineering Model hardware at the 10 kW power level, was conducted by the winning vendor from the first phase of the effort. Both breadboard units and the single engineering model power plant were delivered to NASA for independent testing. This poster presentation will present a summary of both phases of the development effort, along with a discussion of test results of the PEM fuel cell engineering model under simulated mission conditions.

  14. Development of molten carbonate fuel cell technology at M-C Power Corporation

    SciTech Connect

    Dilger, D.

    1996-04-01

    M-C Power Corporation was founded in 1987 with the mission to further develop and subsequently commercialize molten carbonate fuel cells (MCFC). The technology chosen for commercialization was initially developed by the Institute of Gas technology (IGT). At the center of this MCFC technology is the Internally Manifolded Heat EXchange (IMHEX) separator plate design. The IMHEX technology design provides several functions within one component assembly. These functions include integrating the gas manifold structure into the fuel cell stack, separating the fuel gas stream from the oxidant gas stream, providing the required electrical contact between cells to achieve desired power output, and removing excess heat generated in the electrochemical process. Development of this MCFC technology from lab-scale sizes too a commercial area size of 1m{sup 2} has focused our efforts an demonstrating feasibility and evolutionary progress. The development effort will culminate in a proof-of-concept- 250kW power plant demonstration in 1996. The remainder of our commercialization program focuses upon lowering the costs associated with the MCFC power plant system in low production volumes.

  15. Manual of phosphoric acid fuel cell power plant optimization model and computer program

    NASA Technical Reports Server (NTRS)

    Lu, C. Y.; Alkasab, K. A.

    1984-01-01

    An optimized cost and performance model for a phosphoric acid fuel cell power plant system was derived and developed into a modular FORTRAN computer code. Cost, energy, mass, and electrochemical analyses were combined to develop a mathematical model for optimizing the steam to methane ratio in the reformer, hydrogen utilization in the PAFC plates per stack. The nonlinear programming code, COMPUTE, was used to solve this model, in which the method of mixed penalty function combined with Hooke and Jeeves pattern search was chosen to evaluate this specific optimization problem.

  16. New Power Sources for the 21st Century: From Batteries to Fuel Cells

    NASA Astrophysics Data System (ADS)

    Taylor, Kathleen C.

    1998-03-01

    Promised substantial benefits for air quality and fuel efficiency are the motivation for the application of electrochemical based power sources for transportation. General Motors' EV-1 introduced in the marketplace in 1997 is the first modern purpose-built electric vehicle. In the future we anticipate the increased emphasis industry-wide on 'electrochemical engines' for a clean environment. Advanced batteries and fuel cell systems currently under development are the enabling technologies for growing market penetration of electric and hybrid vehicles throughout the 21st century.

  17. Hydrogen Gas Production from Nuclear Power Plant in Relation to Hydrogen Fuel Cell Technologies Nowadays

    NASA Astrophysics Data System (ADS)

    Yusibani, Elin; Kamil, Insan; Suud, Zaki

    2010-06-01

    Recently, world has been confused by issues of energy resourcing, including fossil fuel use, global warming, and sustainable energy generation. Hydrogen may become the choice for future fuel of combustion engine. Hydrogen is an environmentally clean source of energy to end-users, particularly in transportation applications because without release of pollutants at the point of end use. Hydrogen may be produced from water using the process of electrolysis. One of the GEN-IV reactors nuclear projects (HTGRs, HTR, VHTR) is also can produce hydrogen from the process. In the present study, hydrogen gas production from nuclear power plant is reviewed in relation to commercialization of hydrogen fuel cell technologies nowadays.

  18. Water removal studies on high power hydrogen-oxygen fuel cells with alkaline electrolytes

    NASA Astrophysics Data System (ADS)

    Kordesch, K.; Oliveira, J. C. T.; Gruber, Ch.; Winkler, G.

    1989-08-01

    Research in verification of bipolar fuel cell design, containing mass-produceable all-carbon electrodes which can be used in alkaline or acidic cells with liquid or immobilized (matrix) electrolytes, is described. Spin-offs from the research related to the Hermes manned spaceplane could be useful for applications on Earth. Peak-power plants, electric vehicles and storage devices used in combination with renewable energy sources could all benefit from the research. A subsequent investigation of water transpiration properties of carbon electrodes is described.

  19. Monolithic solid oxide fuel cell technology advancement for coal- based power generation. Quarterly report, December 1991

    SciTech Connect

    Not Available

    1992-01-15

    The program is conducted by a team consisting of AiResearch Los Angeles Division of Allied-Signal Aerospace Company and Argonne National Laboratory (ANL). The objective of the program is to advance materials and fabrication methodologies to develop a monolithic solid oxide fuel cell (MSOFC) system capable of meeting performance, life, and cost goals for coal-based power generation. The program focuses on materials research and development, fabrication process development, cell/stack performance testing and characterization, cost and system analysis, and quality development.

  20. Monolithic solid oxide fuel cell technology advancement for coal- based power generation

    SciTech Connect

    Not Available

    1992-01-15

    The program is conducted by a team consisting of AiResearch Los Angeles Division of Allied-Signal Aerospace Company and Argonne National Laboratory (ANL). The objective of the program is to advance materials and fabrication methodologies to develop a monolithic solid oxide fuel cell (MSOFC) system capable of meeting performance, life, and cost goals for coal-based power generation. The program focuses on materials research and development, fabrication process development, cell/stack performance testing and characterization, cost and system analysis, and quality development.

  1. Hydrogen Gas Production from Nuclear Power Plant in Relation to Hydrogen Fuel Cell Technologies Nowadays

    SciTech Connect

    Yusibani, Elin; Kamil, Insan; Suud, Zaki

    2010-06-22

    Recently, world has been confused by issues of energy resourcing, including fossil fuel use, global warming, and sustainable energy generation. Hydrogen may become the choice for future fuel of combustion engine. Hydrogen is an environmentally clean source of energy to end-users, particularly in transportation applications because without release of pollutants at the point of end use. Hydrogen may be produced from water using the process of electrolysis. One of the GEN-IV reactors nuclear projects (HTGRs, HTR, VHTR) is also can produce hydrogen from the process. In the present study, hydrogen gas production from nuclear power plant is reviewed in relation to commercialization of hydrogen fuel cell technologies nowadays.

  2. Develop and test fuel cell powered on-site integrated total energy systems: Phase 3: Full-scale power plant development

    NASA Technical Reports Server (NTRS)

    1982-01-01

    The development of a commercially viable and cost-effective phospheric acid fuel cell powered on-site integrated energy system (OS/IES) is described. The fuel cell offers energy efficients in the range of 35-40% of the higher heating value of available fuels in the form of electrical energy. In addition, by utilizing the thermal energy generated for heating, ventilating and air-conditioning (HVAC), a fuel cell OS/IES could provide total energy efficiencies in the neighborhood of 80%. Also, the Engelhard fuel cell OS/IES offers the important incentive of replacing imported oil with domestically produced methanol, including coal-derived methanol.

  3. Parallel operation characteristics of PEM fuel cell and microturbine power plants

    NASA Astrophysics Data System (ADS)

    Uzunoglu, M.; Onar, O.; El-Sharkh, M. Y.; Sisworahardjo, N. S.; Rahman, A.; Alam, M. S.

    This paper reports on the dynamic behavior of a 250 kW proton exchange membrane fuel cell power plant (PEM FCPP) and a 250 kW microturbine (MT) when operating in parallel. A load sharing control scheme is used to distribute the load equally between the PEM FCPP and the MT. For stand alone operation of a PEM FCPP, a set of batteries or ultracapacitors are needed in order to satisfy the power mismatch during transient periods. Using MT in parallel with the PEM FCPP helps in eliminating the need for storage devices. Models for the PEM FCPP and the MT with power, voltage and speed controls are used to determine the dynamic response of the system to a step change in the load. Simulation results indicate viability of parallel operation of the PEM FCPP and the MT. These results are obtained using MATLAB ®, Simulink ®, and SimPowerSystems ®.

  4. Cost Study for Manufacturing of Solid Oxide Fuel Cell Power Systems

    SciTech Connect

    Weimar, Mark R.; Chick, Lawrence A.; Gotthold, David W.; Whyatt, Greg A.

    2013-09-30

    Solid oxide fuel cell (SOFC) power systems can be designed to produce electricity from fossil fuels at extremely high net efficiencies, approaching 70%. However, in order to penetrate commercial markets to an extent that significantly impacts world fuel consumption, their cost will need to be competitive with alternative generating systems, such as gas turbines. This report discusses a cost model developed at PNNL to estimate the manufacturing cost of SOFC power systems sized for ground-based distributed generation. The power system design was developed at PNNL in a study on the feasibility of using SOFC power systems on more electric aircraft to replace the main engine-mounted electrical generators [Whyatt and Chick, 2012]. We chose to study that design because the projected efficiency was high (70%) and the generating capacity was suitable for ground-based distributed generation (270 kW).

  5. The changing nature of the power generation market — does it create opportunities for fuel cells?

    NASA Astrophysics Data System (ADS)

    Cragg, C. T.

    This paper surveys the global power industry seeking trends that might encourage greater use of full cells. The subject is broken into four basic themes: (i) an increasing demand for electricity, and this may not be solved by the traditional form of the integrated state-owned, centralised power utility, with a large infrastructure grid attached, the load curves of these integrated grids becoming unmanageable; (ii) a general trend towards privatisation and deregulation in the power sector, that is shifting its control from an engineering to a commercial paradigm, with unforseen consequences; (iii) contrary to (ii), the need for supplying security in its most basic sense is increasing rather than declining as power-dependent technology becomes progressively more important in the modern economy, and (iv) the trend in technology, particularly environmental-friendly technology, is towards smaller size of production centres. Within these inter-related themes these are encouraging prospects for the fuel cell community.

  6. H[sub 2]/Cl[sub 2] fuel cells for power and HCl production - chemical cogeneration

    DOEpatents

    Gelb, A.H.

    1991-08-20

    A fuel cell for the electrolytic production of hydrogen chloride and the generation of electric energy from hydrogen and chlorine gas is disclosed. In typical application, the fuel cell operates from the hydrogen and chlorine gas generated by a chlorine electrolysis generator. The hydrogen chloride output is used to maintain acidity in the anode compartment of the electrolysis cells, and the electric energy provided from the fuel cell is used to power a portion of the electrolysis cells in the chlorine generator or for other chlorine generator electric demands. The fuel cell itself is typically formed by a passage for the flow of hydrogen chloride or hydrogen chloride and sodium chloride electrolyte between anode and cathode gas diffusion electrodes. 3 figures.

  7. H.sub.2 /C.sub.12 fuel cells for power and HCl production - chemical cogeneration

    DOEpatents

    Gelb, Alan H.

    1991-01-01

    A fuel cell for the electrolytic production of hydrogen chloride and the generation of electric energy from hydrogen and chlorine gas is disclosed. In typical application, the fuel cell operates from the hydrogen and chlorine gas generated by a chlorine electrolysis generator. The hydrogen chloride output is used to maintain acidity in the anode compartment of the electrolysis cells, and the electric energy provided from the fuel cell is used to power a portion of the electrolysis cells in the chlorine generator or for other chlorine generator electric demands. The fuel cell itself is typically formed by a passage for the flow of hydrogen chloride or hydrogen chloride and sodium chloride electrolyte between anode and cathode gas diffusion electrodes, the HCl increa This invention was made with Government support under Contract No. DE-AC02-86ER80366 with the Department of Energy and the United States Government has certain rights thereto.

  8. An application of indirect model reference adaptive control to a low-power proton exchange membrane fuel cell

    NASA Astrophysics Data System (ADS)

    Yang, Yee-Pien; Liu, Zhao-Wei; Wang, Fu-Cheng

    2008-05-01

    Nonlinearity and the time-varying dynamics of fuel cell systems make it complex to design a controller for improving output performance. This paper introduces an application of a model reference adaptive control to a low-power proton exchange membrane (PEM) fuel cell system, which consists of three main components: a fuel cell stack, an air pump to supply air, and a solenoid valve to adjust hydrogen flow. From the system perspective, the dynamic model of the PEM fuel cell stack can be expressed as a multivariable configuration of two inputs, hydrogen and air-flow rates, and two outputs, cell voltage and current. The corresponding transfer functions can be identified off-line to describe the linearized dynamics with a finite order at a certain operating point, and are written in a discrete-time auto-regressive moving-average model for on-line estimation of parameters. This provides a strategy of regulating the voltage and current of the fuel cell by adaptively adjusting the flow rates of air and hydrogen. Experiments show that the proposed adaptive controller is robust to the variation of fuel cell system dynamics and power request. Additionally, it helps decrease fuel consumption and relieves the DC/DC converter in regulating the fluctuating cell voltage.

  9. Making the grid the backup: Utility applications for fuel cell power

    SciTech Connect

    Eklof, S.L.

    1996-12-31

    Fuel cells are recognized as a versatile power generation option and accepted component of SMUD`s ART Program. SMUD has received wide support and recognition for promoting and implementing fuel cell power plants, as well as other innovative generation, based primarily on technological factors. Current economic and technical realities in the electric generation market highlight other important factors, such as the cost involved to develop a slate of such resources. The goal now is to develop only those select quality resources most likely to become commercially viable in the near future. The challenge becomes the identification of candidate technologies with the greatest potential, and then matching the technologies with the applications that will help to make them successful. Utility participation in this development is critical so as to provide the industry with case examples of advanced technologies that can be applied in a way beneficial to both the utility and its customers. The ART resource acquisitions provide the experience base upon which to guide this selection process, and should bring about the cost reductions and reliability improvements sought.

  10. Fuel Preprocessor (FPP) for a Solid Oxide Fuel Cell Auxiliary Power Unit

    SciTech Connect

    M. Namazian, S. Sethuraman and G. Venkataraman

    2004-12-31

    Auxiliary Power Units (APUs), driven by truck engines, consume over 800 million gallon of diesel fuel while idling. Use of separate SOFC based APUs are an excellent choice to reduce the cost and pollution associated with producing auxiliary power. However, diesel fuel is a challenging fuel to use in fuel cell systems because it has heavy hydrocarbons that can transform into carbon deposits and gums that can block passages and deactivate fuel reformer and fuel cell reactor elements. The work reported herein addresses the challenges associated with the diesel fuel sulfur and carbon producing contaminants in a Fuel Preprocessor (FPP). FPP processes the diesel fuel onboard and ahead of the reformer to reduce its carbon deposition tendency and its sulfur content, thus producing a fuel suitable for SOFC APU systems. The goal of this DOE supported Invention and Innovation program was to design, develop and test a prototype Fuel Preprocessor (FPP) that efficiently and safely converts the diesel fuel into a clean fuel suitable for a SOFC APU system. The goals were achieved. A 5 kWe FPP was designed, developed and tested. It was demonstrated that FPP removes over 80% of the fuel sulfur and over 90% of its carbon residues and it was demonstrated that FPP performance exceeds the original project goals.

  11. Fuel cell powered small unmanned aerial systems (UASs) for extended endurance flights

    NASA Astrophysics Data System (ADS)

    Chu, Deryn; Jiang, R.; Dunbar, Z.; Grew, Kyle; McClure, J.

    2015-05-01

    Small unmanned aerial systems (UASs) have been used for military applications and have additional potential for commercial applications [1-4]. For the military, these systems provide valuable intelligence, surveillance, reconnaissance and target acquisition (ISRTA) capabilities for units at the infantry, battalion, and company levels. The small UASs are light-weight, manportable, can be hand-launched, and are capable of carrying payloads. Currently, most small UASs are powered by lithium-ion or lithium polymer batteries; however, the flight endurance is usually limited less than two hours and requires frequent battery replacement. Long endurance small UAS flights have been demonstrated through the implementation of a fuel cell system. For instance, a propane fueled solid oxide fuel cell (SOFC) stack has been used to power a small UAS and shown to extend mission flight time. The research and development efforts presented here not only apply to small UASs, but also provide merit to the viability of extending mission operations for other unmanned systems applications.

  12. Energy management of fuel cell/battery/supercapacitor hybrid power source for vehicle applications

    NASA Astrophysics Data System (ADS)

    Thounthong, Phatiphat; Raël, Stephane; Davat, Bernard

    This paper proposes a perfect energy source supplied by a polymer electrolyte membrane fuel cell (PEMFC) as a main power source and storage devices: battery and supercapacitor, for modern distributed generation system, particularly for future fuel cell vehicle applications. The energy in hybrid system is balanced by the dc bus voltage regulation. A supercapacitor module, as a high dynamic and high power density device, functions for supplying energy to regulate a dc bus voltage. A battery module, as a high energy density device, operates for supplying energy to a supercapacitor bank to keep it charged. A FC, as a slowest dynamic source in this system, functions to supply energy to a battery bank in order to keep it charged. Therefore, there are three voltage control loops: dc bus voltage regulated by a supercapacitor bank, supercapacitor voltage regulated by a battery bank, and battery voltage regulated by a FC. To authenticate the proposed control algorithm, a hardware system in our laboratory is realized by analog circuits and numerical calculation by dSPACE. Experimental results with small-scale devices (a PEMFC: 500-W, 50-A; a battery bank: 68-Ah, 24-V; and a supercapacitor bank: 292-F, 30-V, 500-A) corroborate the excellent control principle during motor drive cycle.

  13. Development of planar solid oxide fuel cells for power generation applications

    SciTech Connect

    Minh, N.Q.

    1996-04-01

    Planar solid oxide fuel cells (SOFCs) are presently being developed for a variety of electric power generation application. The planar design offers simple cell geometry, high power density, and multiple fabrication and gas manifolding options. Planar SOFC technology has received much attention recently, and significant progress has been made in this area. Recent effort at AlliedSignal has focused on the development of high-performance, lightweight planar SOFCs, having thin-electrolyte films, that can be operated efficiently at reduced temperatures (< 1000{degrees}C). The advantages of reduced-temperature operation include wider material choice (including use of metallic interconnects), expected longer cell life, reduced thermal stress, improved reliability, and reduced fuel cell cost. The key aspect in the development of thin-film SIFCs is to incorporate the thin electrolyte layer into the desired structure of cells in a manner that yields the required characteristics. AlliedSignal has developed a simple and cost-effective method based on tape calendering for the fabrication of thin-electrolyte SOFCs. Thin-electrolyte cells made by tape calendering have shown extraordinary performance, e.g., producing more than 500mW/cm{sup 2} at 700{degrees}C and 800mW/cm{sup 2} at 800{degrees}C with hydrogen as fuel and air is oxidant. thin-electrolyte single cells have been incorporated into a compliant metallic stack structure and operated at reduced and operated at reduced-temperature conditions.

  14. Method of Fabrication of High Power Density Solid Oxide Fuel Cells

    DOEpatents

    Pham, Ai Quoc; Glass, Robert S.

    2008-09-09

    A method for producing ultra-high power density solid oxide fuel cells (SOFCs). The method involves the formation of a multilayer structure cells wherein a buffer layer of doped-ceria is deposited intermediate a zirconia electrolyte and a cobalt iron based electrode using a colloidal spray deposition (CSD) technique. For example, a cobalt iron based cathode composed of (La,Sr)(Co,Fe)O(LSCF) may be deposited on a zirconia electrolyte via a buffer layer of doped-ceria deposited by the CSD technique. The thus formed SOFC have a power density of 1400 mW/cm.sup.2 at 600.degree. C. and 900 mW/cm.sup.2 at 700.degree. C. which constitutes a 2-3 times increased in power density over conventionally produced SOFCs.

  15. Direct hydrocarbon fuel cells

    DOEpatents

    Barnett, Scott A.; Lai, Tammy; Liu, Jiang

    2010-05-04

    The direct electrochemical oxidation of hydrocarbons in solid oxide fuel cells, to generate greater power densities at lower temperatures without carbon deposition. The performance obtained is comparable to that of fuel cells used for hydrogen, and is achieved by using novel anode composites at low operating temperatures. Such solid oxide fuel cells, regardless of fuel source or operation, can be configured advantageously using the structural geometries of this invention.

  16. A mathematical model of the maximum power density attainable in an alkaline hydrogen/oxygen fuel cell

    NASA Technical Reports Server (NTRS)

    Kimble, Michael C.; White, Ralph E.

    1991-01-01

    A mathematical model of a hydrogen/oxygen alkaline fuel cell is presented that can be used to predict the polarization behavior under various power loads. The major limitations to achieving high power densities are indicated and methods to increase the maximum attainable power density are suggested. The alkaline fuel cell model describes the phenomena occurring in the solid, liquid, and gaseous phases of the anode, separator, and cathode regions based on porous electrode theory applied to three phases. Fundamental equations of chemical engineering that describe conservation of mass and charge, species transport, and kinetic phenomena are used to develop the model by treating all phases as a homogeneous continuum.

  17. Fuel cells provide a revenue-generating solution to power quality problems

    SciTech Connect

    King, J.M. Jr.

    1996-03-01

    Electric power quality and reliability are becoming increasingly important as computers and microprocessors assume a larger role in commercial, health care and industrial buildings and processes. At the same time, constraints on transmission and distribution of power from central stations are making local areas vulnerable to low voltage, load addition limitations, power quality and power reliability problems. Many customers currently utilize some form of premium power in the form of standby generators and/or UPS systems. These include customers where continuous power is required because of health and safety or security reasons (hospitals, nursing homes, places of public assembly, air traffic control, military installations, telecommunications, etc.) These also include customers with industrial or commercial processes which can`t tolerance an interruption of power because of product loss or equipment damage. The paper discusses the use of the PC25 fuel cell power plant for backup and parallel power supplies for critical industrial applications. Several PC25 installations are described: the use of propane in a PC25; the use by rural cooperatives; and a demonstration of PC25 technology using landfill gas.

  18. Enhanced power production from microbial fuel cells with high cell density culture.

    PubMed

    Zhai, Dan-Dan; Li, Bing; Sun, Jian-Zhong; Sun, De-Zhen; Si, Rong-Wei; Yong, Yang-Chun

    2016-01-01

    Improvement of power production in a microbial fuel cell (MFC) with a high cell density culture strategy was developed. By using high cell density culture, the voltage output and power density output of the MFC were enhanced about 0.6 and 1.6 times compared to the control, respectively. Further analysis showed that riboflavin concentration in the MFC was dramatically increased from 0.1 mg/L to 1.2 mg/L by high cell density culture. Moreover, the biofilm formation on the anode surface was significantly enhanced by this new strategy. The increased accumulation of electron shuttle (riboflavin) as well as enhanced biofilm formation contributed to the improvement in anodic electrochemical activity and these factors were the underlying mechanism for MFC performance improvement by high cell density culture. This work demonstrated that high cell density culture would be a simple and practical strategy for MFC manipulation. PMID:27148719

  19. Auxiliary power unit based on a solid oxide fuel cell and fuelled with diesel

    NASA Astrophysics Data System (ADS)

    Lawrence, Jeremy; Boltze, Matthias

    An auxiliary power unit (APU) is presented that is fuelled with diesel, thermally self-sustaining, and based on a solid oxide fuel cell (SOFC). The APU is rated at 1 kW electrical, and can generate electrical power after a 3 h warm-up phase. System features include a "dry" catalytic partial oxidation (CPOX) diesel reformer, a 30 cell SOFC stack with an open cathode, and a porous-media afterburner. The APU does not require a supply of external water. The SOFC stack is an outcome of a development partnership with H.C. Starck GmbH and Fraunhofer IKTS, and is discussed in detail in an accompanying paper.

  20. Fuel-Cell Power Systems Incorporating Mg-Based H2 Generators

    NASA Technical Reports Server (NTRS)

    Kindler, Andrew; Narayan, Sri R.

    2009-01-01

    Two hydrogen generators based on reactions involving magnesium and steam have been proposed as means for generating the fuel (hydrogen gas) for such fuel-cell power systems as those to be used in the drive systems of advanced motor vehicles. The hydrogen generators would make it unnecessary to rely on any of the hydrogen storage systems developed thus far that are, variously, too expensive, too heavy, too bulky, and/or too unsafe to be practical. The two proposed hydrogen generators are denoted basic and advanced, respectively. In the basic hydrogen generator (see figure), steam at a temperature greater than or equals 330 C would be fed into a reactor charged with magnesium, wherein hydrogen would be released in the exothermic reaction Mg + H2O yields MgO + H2. The steam would be made in a flash boiler. To initiate the reaction, the boiler could be heated electrically by energy borrowed from a storage battery that would be recharged during normal operation of the associated fuel-cell subsystem. Once the reaction was underway, heat from the reaction would be fed to the boiler. If the boiler were made an integral part of the hydrogen-generator reactor vessel, then the problem of transfer of heat from the reactor to the boiler would be greatly simplified. A pump would be used to feed water from a storage tank to the boiler.

  1. Investigation of an integrated switchgrass gasification/fuel cell power plant. Final report for Phase 1 of the Chariton Valley Biomass Power Project

    SciTech Connect

    Brown, R.C.; Smeenk, J.; Steinfeld, G.

    1998-09-30

    The Chariton Valley Biomass Power Project, sponsored by the US Department of Energy Biomass Power Program, has the goal of converting switchgrass grown on marginal farmland in southern Iowa into electric power. Two energy conversion options are under evaluation: co-firing switchgrass with coal in an existing utility boiler and gasification of switchgrass for use in a carbonate fuel cell. This paper describes the second option under investigation. The gasification study includes both experimental testing in a pilot-scale gasifier and computer simulation of carbonate fuel cell performance when operated on gas derived from switchgrass. Options for comprehensive system integration between a carbonate fuel cell and the gasification system are being evaluated. Use of waste heat from the carbonate fuel cell to maximize overall integrated plant efficiency is being examined. Existing fuel cell power plant design elements will be used, as appropriate, in the integration of the gasifier and fuel cell power plant to minimize cost complexity and risk. The gasification experiments are being performed by Iowa State University and the fuel cell evaluations are being performed by Energy Research Corporation.

  2. Fuel cell market applications

    SciTech Connect

    Williams, M.C.

    1995-12-31

    This is a review of the US (and international) fuel cell development for the stationary power generation market. Besides DOE, GRI, and EPRI sponsorship, the US fuel cell program has over 40% cost-sharing from the private sector. Support is provided by user groups with over 75 utility and other end-user members. Objectives are to develop and demonstrate cost-effective fuel cell power generation which can initially be commercialized into various market applications using natural gas fuel by the year 2000. Types of fuel cells being developed include PAFC (phosphoric acid), MCFC (molten carbonate), and SOFC (solid oxide); status of each is reported. Potential international applications are reviewed also. Fuel cells are viewed as a force in dispersed power generation, distributed power, cogeneration, and deregulated industry. Specific fuel cell attributes are discussed: Fuel cells promise to be one of the most reliable power sources; they are now being used in critical uninterruptible power systems. They need hydrogen which can be generated internally from natural gas, coal gas, methanol landfill gas, or other fuels containing hydrocarbons. Finally, fuel cell development and market applications in Japan are reviewed briefly.

  3. The Development of Fuel Cell Technology for Electric Power Generation - From Spacecraft Applications to the Hydrogen Economy

    NASA Technical Reports Server (NTRS)

    Scott, John H.

    2005-01-01

    The fuel cell uses a catalyzed reaction between a fuel and an oxidizer to directly produce electricity. Its high theoretical efficiency and low temperature operation made it a subject of much study upon its invention ca. 1900, but its relatively high life cycle costs kept it as "solution in search of a problem" for its first half century. The first problem for which fuel cells presented a cost effective solution was, starting in the 1960's that of a power source for NASA's manned spacecraft. NASA thus invested, and continues to invest, in the development of fuel cell power plants for this application. However, starting in the mid-1990's, prospective environmental regulations have driven increased governmental and industrial interest in "green power" and the "Hydrogen Economy." This has in turn stimulated greatly increased investment in fuel cell development for a variety of terrestrial applications. This investment is bringing about notable advances in fuel cell technology, but these advances are often in directions quite different from those needed for NASA spacecraft applications. This environment thus presents both opportunities and challenges for NASA's manned space program.

  4. Micro fuel cell

    SciTech Connect

    Zook, L.A.; Vanderborgh, N.E.; Hockaday, R.

    1998-12-31

    An ambient temperature, liquid feed, direct methanol fuel cell device is under development. A metal barrier layer was used to block methanol crossover from the anode to the cathode side while still allowing for the transport of protons from the anode to the cathode. A direct methanol fuel cell (DMFC) is an electrochemical engine that converts chemical energy into clean electrical power by the direct oxidation of methanol at the fuel cell anode. This direct use of a liquid fuel eliminates the need for a reformer to convert the fuel to hydrogen before it is fed into the fuel cell.

  5. Generating power from transdermal extracts using a multi-electrode miniature enzymatic fuel cell.

    PubMed

    du Toit, Hendrik; Rashidi, Razleen; Ferdani, Dominic W; Delgado-Charro, Maria Begoña; Sangan, Carl M; Di Lorenzo, Mirella

    2016-04-15

    The development of self-powered wearable biodevices is highly attractive for a number of applications, such as health monitoring and drug delivery. Enzymatic fuel cells (EFCs) hold great potential as power sources for such devices, since they can generate power from physiological fluids and operate at body temperature. In this study, we present a cascade of three EFCs embedded in a compact and handy single channel device and we demonstrate for the first time power generation from iontophoresis extracts obtained from pig skin. The EFCs implement non-toxic highly-porous gold electrodes; an easy-to-reproduce procedure is adopted for the immobilization of glucose oxidase and laccase at the anode and cathode respectively; no external mediators are used; and the system design can easily be further miniaturized. When electrically connected in parallel, the EFCs generated a power output close to the sum of the power generated by each unit, with peak values of 0.7 µW (flow-through mode) and 0.4 µW (batch mode), at a glucose concentration of 27 mM. When the device was fed with transdermal extracts, containing only 30 μM of glucose, the average peak power was proportionally lower (0.004 µW). PMID:26655181

  6. Distributed multiple-anodes benthic microbial fuel cell as reliable power source for subsea sensors

    NASA Astrophysics Data System (ADS)

    Liu, Bingchuan; Weinstein, Alyssa; Kolln, Michael; Garrett, Caleb; Wang, Lei; Bagtzoglou, Amvrossios; Karra, Udayarka; Li, Yan; Li, Baikun

    2015-07-01

    A new type distributed benthic microbial fuel cell (MFC) (DBMFC) consisting of 18 MFC arrays was developed to enhance the robustness and stability of the power source for subsea sensor networks. A power management system (PMS) was integrated into the DBMFC system to boost the power output for two temperature sensors. The PMS was specifically designed with 18 charge pumps capable of simultaneously harvesting energy from 6 MFC units (18 anodes total) in the DBMFC system. The pilot scale DBMFC (total sediment volume: 1 m3) with continuous ocean water supply showed that the power outputs of individual MFC units were affected by the organic carbon and nitrogen contents in the sediment pore water. The MFC units with higher power output resulted in faster charging/discharging rate of the PMS supercapacitor. Manual disconnection of anodes from the PMS was conducted to simulate the anode malfunction caused by bioturbation. Fewer functional anodes (e.g. 12 out of 18 anodes were disconnected) slowed the charging/discharging rate of the PMS supercapacitor but still supported the PMS to regularly power two sensors. This scale-up DBMFC/PMS/sensor study demonstrated that multiple MFC units with multiple PMS substantially enhanced the stability and robustness of power supply to subsea sensors.

  7. Regenerative fuel cells for High Altitude Long Endurance Solar Powered Aircraft

    NASA Astrophysics Data System (ADS)

    Mitlitsky, F.; Colella, N. J.; Myers, B.; Anderson, C. J.

    1993-06-01

    High Altitude Long Endurance (HALE) unmanned missions appear to be feasible using a lightweight, high efficiency, span-loaded, Solar Powered Aircraft (SPA) which includes a Regenerative Fuel Cell (RFC) system and novel tankage for energy storage. An existing flightworthy electric powered flying wing design was modified to incorporate present and near-term technologies in energy storage, power electronics, aerodynamics, and guidance and control in order to substantiate feasibility. The design philosophy was to work with vendors to identify affordable near-term technological opportunities that could be applied to existing designs in order to reduce weight, increase reliability, and maintain adequate efficiency of components for delivery within 18 months. The energy storage subsystem for a HALE SPA is a key driver for the entire vehicle because it can represent up to half of the vehicle weight and most missions of interest require the specific energy to be considerably higher than 200 W-hr/kg for many cycles. This stringent specific energy requirement precludes the use of rechargeable batteries or flywheels and suggests examination of various RFC designs. An RFC system using lightweight tankage, a single fuel cell (FC) stack, and a single electrolyzer (EC) stack separated by the length of a spar segment (up to 39 ft), has specific energy of approximately 300 W-hr/kg with 45% efficiency, which is adequate for HALE SPA requirements. However, this design has complexity and weight penalties associated with thermal management, electrical wiring, plumbing, and structural weight. A more elegant solution is to use unitized RFC stacks (reversible stacks that act as both FC's and EC's) because these systems have superior specific energy, scale to smaller systems more favorably, and have intrinsically simpler thermal management.

  8. Ocean Microbial Fuel Cell: Power Source and Research Tool for Studying Marine Biogeochemistry

    NASA Astrophysics Data System (ADS)

    Reimers, C. E.; Girguis, P.; Westall, J. C.; Nielsen, M. E.

    2007-05-01

    Ocean microbial fuel cells (OMFCs) are devices capable of producing modest levels of electrical power. The cells are ultimately driven by the oxidation of marine organic matter at the anode and reduction of dissolved oxygen at the cathode, but microbial transformations and electrochemically active intermediates play important roles in the overall process of electricity generation. By separating the factors that affect the performance of OMFCs into components of an equivalent circuit and manipulating these factors in laboratory and field experiments, we are gaining new insight into how specific redox reactions, sources of organic matter, and mass transport at small and intermediate scales may enrich environments with certain groups of microorganisms that in turn regulate anaerobic organic matter degradation. This talk will illustrate these relationships with the results from at least four experiments in which either fresh plankton, or substrates within continental margin sediments, fuelled the OMFCs. In each example, reduced sulfur compounds were found to be major electron carriers to the fuel cell anode. These intermediates came from a variety of sources including sulfide generated from sulfate reduction in mixed solutions surrounding the electrode, sulfide generated distally but transported by pore-water diffusion and advection, iron monosulfides and pyrite present is a sediment matrix centimeters from the electrode, and sulfide or polysulfide produced within an electrode biofilm. To illustrate a practical application of an OMFC, we are currently constructing a benthic cell that will power a sonic receiver in a network of underwater sensors. The form of this OMFC resembles a benthic chamber with a footprint of one square meter. It should be capable of supplying electrical power and regulating its output for years to decades.

  9. Regenerative fuel cells for High Altitude Long Endurance Solar Powered Aircraft

    SciTech Connect

    Mitlitsky, F.; Colella, N.J.; Myers, B.; Anderson, C.J.

    1993-06-02

    High Altitude Long Endurance (HALE) unmanned missions appear to be feasible using a lightweight, high efficiency, span-loaded, Solar Powered Aircraft (SPA) which includes a Regenerative Fuel Cell (RFC) system and novel tankage for energy storage. An existing flightworthy electric powered flying wing design was modified to incorporate present and near-term technologies in energy storage, power electronics, aerodynamics, and guidance and control in order to design philosophy was to work with vendors to identify affordable near-term technological opportunities that could be applied to existing designs in order to reduce weight, increase reliability, and maintain adequate efficiency of components for delivery within 18 months. The energy storage subsystem for a HALE SPA is a key driver for the entire vehicle because it can represent up to half of the vehicle weight and most missions of interest require the specific energy to be considerably higher than 200 W-hr/kg for many cycles. This stringent specific energy requirement precludes the use of rechargeable batteries or flywheels and suggests examination of various RFC designs. An RFC system using lightweight tankage, a single fuel cell (FC) stack, and a single electrolyzer (EC) stack separated by the length of a spar segment (up to 39 ft), has specific energy of {approximately}300 W-hr/kg with 45% efficiency, which is adequate for HALE SPA requirements. However, this design has complexity and weight penalties associated with thermal management, electrical wiring, plumbing, and structural weight. A more elegant solution is to use unitized RFC stacks (reversible stacks that act as both FCs and ECs) because these systems have superior specific energy, scale to smaller systems more favorably, and have intrinsically simpler thermal management.

  10. Global Assessment of Hydrogen Technologies – Task 5 Report Use of Fuel Cell Technology in Electric Power Generation

    SciTech Connect

    Fouad, Fouad H.; Peters, Robert W.; Sisiopiku, Virginia P.; Sullivan Andrew J.; Ahluwalia, Rajesh K.

    2007-12-01

    The purpose of this work was to assess the performance of high temperature membranes and observe the impact of different parameters, such as water-to-carbon ratio, carbon formation, hydrogen formation, efficiencies, methane formation, fuel and oxidant utilization, sulfur reduction, and the thermal efficiency/electrical efficiency relationship, on fuel cell performance. A 250 KW PEM fuel cell model was simulated [in conjunction with Argonne National Laboratory (ANL) with the help of the fuel cell computer software model (GCtool)] which would be used to produce power of 250 kW and also produce steam at 120oC that can be used for industrial applications. The performance of the system was examined by estimating the various electrical and thermal efficiencies achievable, and by assessing the effect of supply water temperature, process water temperature, and pressure on thermal performance. It was concluded that increasing the fuel utilization increases the electrical efficiency but decreases the thermal efficiency. The electrical and thermal efficiencies are optimum at ~85% fuel utilization. The low temperature membrane (70oC) is unsuitable for generating high-grade heat suitable for useful cogeneration. The high temperature fuel cells are capable of producing steam through 280oC that can be utilized for industrial applications. Increasing the supply water temperature reduces the efficiency of the radiator. Increasing the supply water temperature beyond the dew point temperature decreases the thermal efficiency with the corresponding decrease in high-grade heat utilization. Increasing the steam pressure decreases the thermal efficiency. The environmental impacts of fuel cell use depend upon the source of the hydrogen rich fuel used. By using pure hydrogen, fuel cells have virtually no emissions except water. Hydrogen is rarely used due to problems with storage and transportation, but in the future, the growth of a “solar hydrogen economy” has been projected

  11. Study of multistage oxidation by flowsheet calculations on a combined heat and power molten carbonate fuel cell plant

    NASA Astrophysics Data System (ADS)

    Au, S. F.; Woudstra, N.; Hemmes, K.

    The multistage oxidation configuration consists of a set of serially connected fuel cell stacks. By connecting the stacks serially, more homogenous current distribution over the cell surface can be achieved resulting in lower irreversible losses. This article presents a detailed assessment of multistage oxidation by flowsheet calculations in which the influence of operating temperature and gas composition on the fuel cell performance is incorporated. A 250 kW molten carbonate fuel cell (MCFC) combined heat and power (CHP) plant is used as reference and the fuel cell stack unit is substituted by two serially connected units ( N=2). Two multistage configurations are examined: (A) both anode and cathode flows are serially connected; (B) only the anode flow is serially connected while the cathode flow is parallel connected. For all systems, the total cell active area, cell current density, overall fuel utilization and gas temperature at the inlet and outlet of the fuel cell array are kept constant. Fuel cell performance at the operating conditions is calculated using a numerical model of the flowsheeting program. Influences of operating temperature and gas composition on the cell performance are incorporated using empirical relations that describe irreversible losses of the cell as function of these parameters. System performances are compared in order to assess the benefits of the multistage oxidation configurations. Differences in performance between the two multistage oxidation configurations are studied by analyzing the difference in exergy loss of stacks, stack power output, cooling requirement and cathode gas massflow and composition. Detailed flowsheet calculations show that the improvement in efficiency is about 0.6% for configuration A, and 0.8% for configuration B. Improvements are obtained by the enhanced fuel cell power output while the expander power output is slightly reduced. Heat output is slightly reduced due to the improved fuel cell conversion

  12. Powering a wireless temperature sensor using sediment microbial fuel cells with vertical arrangement of electrodes

    NASA Astrophysics Data System (ADS)

    Zhang, Fei; Tian, Lei; He, Zhen

    The application of wireless sensors is an important approach for monitoring natural water systems in remote locations; however, limited power sources are a key challenge for successful application of these sensors. Sediment microbial fuel cells (SMFCs) have shown potential as a sustainable power source with low maintenance requirements to power wireless sensors. This study examines electricity generation in lab-scale SMFCs with the sediment from Lake Michigan. Two SMFCs are operated in parallel with a difference in cathode arrangement (floating cathode vs. bottom cathode). The data show that the SMFC with a floating cathode produces more electricity and results in a shorter charging time when an ultracapacitor is connected to the circuit. To control electricity delivery and voltage elevation to a value that can drive a wireless temperature sensor, a power management system (PMS) is developed. With the PMS, both SMFCs can consistently power the wireless temperature sensor for data transmission to a computer, although the number of recorded data within the same period differs. This research provides an effective PMS for power control and valuable experience in SMFC configurations for the next onsite test of the developed SMFCs in Lake Michigan.

  13. Electrochemical decolorization of methyl orange powered by bioelectricity from single-chamber microbial fuel cells.

    PubMed

    Zhang, Baogang; Wang, Zhijun; Zhou, Xiang; Shi, Chunhong; Guo, Huaming; Feng, Chuanping

    2015-04-01

    Methyl orange (MO), a typical azo dye, is a well-known recalcitrant pollutant in dye wastewater. An aeration electrochemical system with single-chamber microbial fuel cell (MFC) as renewable power sources is proposed for MO decolorization. The enhanced color removal efficiency up to 90.4% within 360 min is observed with voltage across the aeration electrolytic reactor fixed at 700 mV. The results from gas chromatography-mass spectrometry (GC-MS) analysis indicate the destruction of MO, with generation of low molecular weight compounds such as benzene derivatives. Comparison experiments imply the indirect electrochemical oxidation of MO by generated H2O2 is mainly responsible for MO decolorization in present study. This work offers a cost-effective electrochemical method for enhancing electrochemical degradation of dyes with bioelectricity generated from MFCs. PMID:25661516

  14. Solid oxide fuel cell power plant with an anode recycle loop turbocharger

    DOEpatents

    Saito, Kazuo; Skiba, Tommy; Patel, Kirtikumar H.

    2015-07-14

    An anode exhaust recycle turbocharger (100) has a turbocharger turbine (102) secured in fluid communication with a compressed oxidant stream within an oxidant inlet line (218) downstream from a compressed oxidant supply (104), and the anode exhaust recycle turbocharger (100) also includes a turbocharger compressor (106) mechanically linked to the turbocharger turbine (102) and secured in fluid communication with a flow of anode exhaust passing through an anode exhaust recycle loop (238) of the solid oxide fuel cell power plant (200). All or a portion of compressed oxidant within an oxidant inlet line (218) drives the turbocharger turbine (102) to thereby compress the anode exhaust stream in the recycle loop (238). A high-temperature, automotive-type turbocharger (100) replaces a recycle loop blower-compressor (52).

  15. Direct N2H4/H2O2 Fuel Cells Powered by Nanoporous Gold Leaves

    PubMed Central

    Yan, Xiuling; Meng, Fanhui; Xie, Yun; Liu, Jianguo; Ding, Yi

    2012-01-01

    Dealloyed nanoporous gold leaves (NPGLs) are found to exhibit high electrocatalytic properties toward both hydrazine (N2H4) oxidation and hydrogen peroxide (H2O2) reduction. This observation allows the implementation of a direct hydrazine-hydrogen peroxide fuel cell (DHHPFC) based on these novel porous membrane catalysts. The effects of fuel and oxidizer flow rate, concentration and cell temperature on the performance of DHHPFC are systematically investigated. With a loading of ~0.1 mg cm−2 Au on each side, an open circuit voltage (OCV) of 1.2 V is obtained at 80°C with a maximum power density 195 mW cm−2, which is 22 times higher than that of commercial Pt/C electrocatalyst at the same noble metal loading. NPGLs thus hold great potential as effective and stable electrocatalysts for DHHPFCs. PMID:23230507

  16. Analysis of a model of fuel cell - gas turbine hybrid power system for enhanced energy efficiency

    NASA Astrophysics Data System (ADS)

    Calay, Rajnish K.; Mustafa, Mohamad Y.; Virk, Mohammad S.; Mustafa, Mahmoud F.

    2012-11-01

    A simple mathematical model to evaluate the performance of FC-GT hybrid system is presented in this paper. The model is used to analyse the influence of various parameters on the performance of a typical hybrid system, where excess heat rejected from the solid-oxide fuel cell stack is utilised to generate additional power through a gas turbine system and to provide heat energy for space heating. The model is based on thermodynamic analysis of various components of the plant and can be adapted for various configurations of the plant components. Because there are many parameters defining the efficiency and work output of the hybrid system, the technique is based on mathematical and graphical optimisation of various parameters; to obtain the maximum efficiency for a given plant configuration.

  17. Fuel cell report to congress

    SciTech Connect

    None, None

    2003-02-28

    This report describes the status of fuel cells for Congressional committees. It focuses on the technical and economic barriers to the use of fuel cells in transportation, portable power, stationary, and distributed power generation applications, and describes the need for public-private cooperative programs to demonstrate the use of fuel cells in commercial-scale applications by 2012. (Department of Energy, February 2003).

  18. Fuel Cell Technical Team Roadmap

    SciTech Connect

    2013-06-01

    The Fuel Cell Technical Team promotes the development of a fuel cell power system for an automotive powertrain that meets the U.S. DRIVE Partnership (United States Driving Research and Innovation for Vehicle efficiency and Energy sustainability) goals.

  19. The use of experimental design to find the operating maximum power point of PEM fuel cells

    SciTech Connect

    Crăciunescu, Aurelian; Pătularu, Laurenţiu; Ciumbulea, Gloria; Olteanu, Valentin; Pitorac, Cristina; Drugan, Elena

    2015-03-10

    Proton Exchange Membrane (PEM) Fuel Cells are difficult to model due to their complex nonlinear nature. In this paper, the development of a PEM Fuel Cells mathematical model based on the Design of Experiment methodology is described. The Design of Experiment provides a very efficient methodology to obtain a mathematical model for the studied multivariable system with only a few experiments. The obtained results can be used for optimization and control of the PEM Fuel Cells systems.

  20. PLATINUM AND FUEL CELLS

    EPA Science Inventory

    Platinum requirements for fuel cell vehicles (FCVS) have been identified as a concern and possible problem with FCV market penetration. Platinum is a necessary component of the electrodes of fuel cell engines that power the vehicles. The platinum is deposited on porous electrodes...

  1. Fuel sensor-less control of a liquid feed fuel cell under dynamic loading conditions for portable power sources (II)

    NASA Astrophysics Data System (ADS)

    Chang, C. L.; Chen, C. Y.; Sung, C. C.; Liou, D. H.; Chang, C. Y.; Cha, H. C.

    This work presents a new fuel sensor-less control scheme for liquid feed fuel cells that is able to control the supply to a fuel cell system for operation under dynamic loading conditions. The control scheme uses cell-operating characteristics, such as potential, current, and power, to regulate the fuel concentration of a liquid feed fuel cell without the need for a fuel concentration sensor. A current integral technique has been developed to calculate the quantity of fuel required at each monitoring cycle, which can be combined with the concentration regulating process to control the fuel supply for stable operation. As verified by systematic experiments, this scheme can effectively control the fuel supply of a liquid feed fuel cell with reduced response time, even under conditions where the membrane electrolyte assembly (MEA) deteriorates gradually. This advance will aid the commercialization of liquid feed fuel cells and make them more adaptable for use in portable and automotive power units such as laptops, e-bikes, and handicap cars.

  2. Performance Evaluation of Electrochem's PEM Fuel Cell Power Plant for NASA's 2nd Generation Reusable Launch Vehicle

    NASA Technical Reports Server (NTRS)

    Kimble, Michael C.; Hoberecht, Mark

    2003-01-01

    NASA's Next Generation Launch Technology (NGLT) program is being developed to meet national needs for civil and commercial space access with goals of reducing the launch costs, increasing the reliability, and reducing the maintenance and operating costs. To this end, NASA is considering an all- electric capability for NGLT vehicles requiring advanced electrical power generation technology at a nominal 20 kW level with peak power capabilities six times the nominal power. The proton exchange membrane (PEM) fuel cell has been identified as a viable candidate to supply this electrical power; however, several technology aspects need to be assessed. Electrochem, Inc., under contract to NASA, has developed a breadboard power generator to address these technical issues with the goal of maximizing the system reliability while minimizing the cost and system complexity. This breadboard generator operates with dry hydrogen and oxygen gas using eductors to recirculate the gases eliminating gas humidification and blowers from the system. Except for a coolant pump, the system design incorporates passive components allowing the fuel cell to readily follow a duty cycle profile and that may operate at high 6:1 peak power levels for 30 second durations. Performance data of the fuel cell stack along with system performance is presented to highlight the benefits of the fuel cell stack design and system design for NGLT vehicles.

  3. Active energy harvesting from microbial fuel cells at the maximum power point without using resistors.

    PubMed

    Wang, Heming; Park, Jae-Do; Ren, Zhiyong

    2012-05-01

    Microbial fuel cell (MFC) technology offers a sustainable approach to harvest electricity from biodegradable materials. Energy production from MFCs has been demonstrated using external resistors or charge pumps, but such methods can only dissipate energy through heat or receive electrons passively from the MFC without any controllability. This study developed a new approach and system that can actively extract energy from MFC reactors at any operating point without using any resistors, especially at the peak power point to maximize energy production. Results show that power harvesting from a recirculating-flow MFC can be well maintained by the maximum power point circuit (MPPC) at its peak power point, while a charge pump was not able to change operating point due to current limitation. Within 18-h test, the energy gained from the MPPC was 76.8 J, 76 times higher than the charge pump (1.0 J) that was commonly used in MFC studies. Both conditions resulted in similar organic removal, but the Coulombic efficiency obtained from the MPPC was 21 times higher than that of the charge pump. Different numbers of capacitors could be used in the MPPC for various energy storage requirements and power supply, and the energy conversion efficiency of the MPPC was further characterized to identify key factors for system improvement. This active energy harvesting approach provides a new perspective for energy harvesting that can maximize MFC energy generation and system controllability. PMID:22486712

  4. Comparative study on power generation of dual-cathode microbial fuel cell according to polarization methods.

    PubMed

    Lee, Kang-yu; Ryu, Wyan-seuk; Cho, Sung-il; Lim, Kyeong-ho

    2015-11-01

    Microbial fuel cells (MFCs) exist in various forms depending on the type of pollutant to be removed and the expected performance. Dual-cathode MFCs, with their simple structure, are capable of removing both organic matter and nitrogen. Moreover, various methods are available for the collection of polarization data, which can be used to calculate the maximum power density, an important factor of MFCs. Many researchers prefer the method of varying the external resistance in a single-cycle due to the short measurement time and high accuracy. This study compared power densities of dual-cathode MFCs in a single-cycle with values calculated over multi-cycles to determine the optimal polarization method. External resistance was varied from high to low and vice versa in the single-cycle, to calculate power density. External resistance was organized in descending order with initial start-up at open circuit voltage (OCV), and then it was organized in descending order again after the initial start-up at 1000 Ω. As a result, power density was underestimated at the anoxic cathode when the external resistance was varied from low to high, and overestimated at the aerobic cathode and anoxic cathode when external resistance at OCV was reduced following initial start-up. In calculating the power densities of dual-cathode MFCs, this paper recommends the method of gradually reducing the external resistance after initial start-up with high external resistance. PMID:26210028

  5. Business Case for a Micro-Combined Heat and Power Fuel Cell System in Commercial Applications

    SciTech Connect

    Brooks, Kriston P.; Makhmalbaf, Atefe; Anderson, David M.; Amaya, Jodi P.; Pilli, Siva Prasad; Srivastava, Viraj; Upton, Jaki F.

    2013-10-30

    Combined heat and power fuel cell systems (CHP-FCSs) provide consistent electrical power and hot water with greater efficiency and lower emissions than alternative sources. These systems can be used either as baseload, grid-connected, or as off-the-grid power sources. This report presents a business case for CHP-FCSs in the range of 5 to 50 kWe. Systems in this power range are considered micro-CHP-FCS. For this particular business case, commercial applications rather than residential or industrial are targeted. To understand the benefits of implementing a micro-CHP-FCS, the characteristics that determine their competitive advantage must first be identified. Locations with high electricity prices and low natural gas prices are ideal locations for micro-CHP-FCSs. Fortunately, these high spark spread locations are generally in the northeastern area of the United States and California where government incentives are already in place to offset the current high cost of the micro-CHP-FCSs. As a result of the inherently high efficiency of a fuel cell and their ability to use the waste heat that is generated as a CHP, they have higher efficiency. This results in lower fuel costs than comparable alternative small-scale power systems (e.g., microturbines and reciprocating engines). A variety of markets should consider micro-CHP-FCSs including those that require both heat and baseload electricity throughout the year. In addition, the reliable power of micro-CHP-FCSs could be beneficial to markets where electrical outages are especially frequent or costly. Greenhouse gas emission levels from micro-CHP-FCSs are 69 percent lower, and the human health costs are 99.9 percent lower, than those attributed to conventional coal-fired power plants. As a result, FCSs can allow a company to advertise as environmentally conscious and provide a bottom-line sales advantage. As a new technology in the early stages of adoption, micro-CHP-FCSs are currently more expensive than alternative

  6. Technical Analysis of Installed Micro-Combined Heat and Power Fuel-Cell System

    SciTech Connect

    Brooks, Kriston P.; Makhmalbaf, Atefe

    2014-10-31

    Combined heat and power fuel cell systems (CHP-FCSs) provide consistent electrical power and hot water with greater efficiency and lower emissions than alternative sources. These systems can be used either as baseload, grid-connected, or as off-the-grid power sources. This report presents a technical analysis of 5 kWe CHP-FCSs installed in different locations in the U.S. At some sites as many as five 5 kWe system is used to provide up to 25kWe of power. Systems in this power range are considered “micro”-CHP-FCS. To better assess performance of micro-CHP-FCS and understand their benefits, the U.S. Department of Energy worked with ClearEdge Power to install fifteen 5-kWe PBI high temperature PEM fuel cells (CE5 models) in the commercial markets of California and Oregon. Pacific Northwest National Laboratory evaluated these systems in terms of their economics, operations, and technical performance. These units were monitored from September 2011 until June 2013. During this time, about 190,000 hours of data were collected and more than 17 billion data points were analyzed. Beginning in July 2013, ten of these systems were gradually replaced with ungraded systems (M5 models) containing phosphoric acid fuel cell technology. The new units were monitored until June 2014 until they went offline because ClearEdge was bought by Doosan at the time and the new manufacturer did not continue to support data collection and maintenance of these units. During these two phases, data was collected at once per second and data analysis techniques were applied to understand behavior of these systems. The results of this analysis indicate that systems installed in the second phase of this demonstration performed much better in terms of availability, consistency in generation, and reliability. The average net electrical power output increased from 4.1 to 4.9 kWe, net heat recovery from 4.7 to 5.4 kWth, and system availability improved from 94% to 95%. The average net system electric

  7. Electric power generation by a submersible microbial fuel cell equipped with a membrane electrode assembly.

    PubMed

    Min, Booki; Poulsen, Finn Willy; Thygesen, Anders; Angelidaki, Irini

    2012-08-01

    Membrane electrode assemblies (MEAs) were incorporated into the cathode chamber of a submersible microbial fuel cell (SMFC). A close contact of the electrodes could produce high power output from SMFC in which anode and cathode electrodes were connected in parallel. In polarization test, the maximum power density was 631 mW/m(2) at current density of 1772 mA/m(2) at 82 Ω. With 180-Ω external resistance, one set of the electrodes on the same side could generate more power density of 832±4 mW/m(2) with current generation of 1923±4 mA/m(2). The anode, inclusive a biofilm behaved ohmic, whereas a Tafel type behavior was observed for the oxygen reduction. The various impedance contributions from electrodes, electrolyte and membrane were analyzed and identified by electrochemical impedance spectroscopy. Air flow rate to the cathode chamber affected microbial voltage generation, and higher power generation was obtained at relatively low air flow less than 2 mL/min. PMID:22705964

  8. System Design of a Natural Gas PEM Fuel Cell Power Plant for Buildings

    SciTech Connect

    Joe Ferrall, Tim Rehg, Vesna Stanic

    2000-09-30

    The following conclusions are made based on this analysis effort: (1) High-temperature PEM data are not available; (2) Stack development effort for Phase II is required; (3) System results are by definition preliminary, mostly due to the immaturity of the high-temperature stack; other components of the system are relatively well defined; (4) The Grotthuss conduction mechanism yields the preferred system characteristics; the Grotthuss conduction mechanism is also much less technically mature than the vehicle mechanism; (5) Fuel processor technology is available today and can be procured for Phase II (steam or ATR); (6) The immaturity of high-temperature membrane technology requires that a robust system design be developed in Phase II that is capable of operating over a wide temperature and pressure range - (a) Unpressurized or Pressurized PEM (Grotthuss mechanism) at 140 C, Highest temperature most favorable, Lowest water requirement most favorable, Pressurized recommended for base loaded operation, Unpressurized may be preferred for load following; (b) Pressurized PEM (vehicle mechanism) at about 100 C, Pressure required for saturation, Fuel cell technology currently available, stack development required. The system analysis and screening evaluation resulted in the identification of the following components for the most promising system: (1) Steam reforming fuel processor; (2) Grotthuss mechanism fuel cell stack operating at 140 C; (3) Means to deliver system waste heat to a cogeneration unit; (4) Pressurized system utilizing a turbocompressor for a base-load power application. If duty cycling is anticipated, the benefits of compression may be offset due to complexity of control. In this case (and even in the base loaded case), the turbocompressor can be replaced with a blower for low-pressure operation.

  9. Modeling of gas turbine - solid oxide fuel cell systems for combined propulsion and power on aircraft

    NASA Astrophysics Data System (ADS)

    Waters, Daniel Francis

    This dissertation investigates the use of gas turbine (GT) engine integrated solid oxide fuel cells (SOFCs) to reduce fuel burn in aircraft with large electrical loads like sensor-laden unmanned air vehicles (UAVs). The concept offers a number of advantages: the GT absorbs many SOFC balance of plant functions (supplying fuel, air, and heat to the fuel cell) thereby reducing the number of components in the system; the GT supplies fuel and pressurized air that significantly increases SOFC performance; heat and unreacted fuel from the SOFC are recaptured by the GT cycle offsetting system-level losses; good transient response of the GT cycle compensates for poor transient response of the SOFC. The net result is a system that can supply more electrical power more efficiently than comparable engine-generator systems with only modest (<10%) decrease in power density. Thermodynamic models of SOFCs, catalytic partial oxidation (CPOx) reactors, and three GT engine types (turbojet, combined exhaust turbofan, separate exhaust turbofan) are developed that account for equilibrium gas phase and electrochemical reaction, pressure losses, and heat losses in ways that capture `down-the-channel' effects (a level of fidelity necessary for making meaningful performance, mass, and volume estimates). Models are created in a NASA-developed environment called Numerical Propulsion System Simulation (NPSS). A sensitivity analysis identifies important design parameters and translates uncertainties in model parameters into uncertainties in overall performance. GT-SOFC integrations reduce fuel burn 3-4% in 50 kW systems on 35 kN rated engines (all types) with overall uncertainty <1%. Reductions of 15-20% are possible at the 200 kW power level. GT-SOFCs are also able to provide more electric power (factors >3 in some cases) than generator-based systems before encountering turbine inlet temperature limits. Aerodynamic drag effects of engine-airframe integration are by far the most important

  10. Analysis and control of an in situ hydrogen generation and fuel cell power system for automotive applications

    NASA Astrophysics Data System (ADS)

    Kolavennu, Panini K.

    A new future in automotive transportation is approaching where vehicles are powered by new, clean and efficient energy sources. While different technologies will contribute to this future, many see fuel cells as the leading long term candidate for becoming the power source for emissions-free, mass produced light vehicles. The development of emissions-free vehicles, which run directly on hydrogen, is the true long term goal. However significant difficulties exist in developing these vehicles, due to hydrogen storage problems. For automotive applications, it is desirable to use a carbon-based hydrogenous fuel. The focus of this research was to analyze a fuel cell system for automotive applications, which generated hydrogen in situ using methane as a fuel source. This system consists of four parts: (1) an in situ hydrogen generation subsystem, (2) a power generation subsystem, (3) a thermal management subsystem and (4) a switching control subsystem. The novelty of this research lies in the fact that the entire system was considered from a systems engineering viewpoint with realistic constraints. A fuel processor subsystem was designed and its volume optimized to less than 100 liters. A relationship between the fuel fed into the fuel processor and the hydrogen coming out of it was developed. Using a fuel cell model an overall relationship between the fuel feed rate and the power output was established. The fuel cell car must be fully operational within a minute or so of a cold-start and must respond to rapidly varying loads. Significant load transitions occur frequently as a result of changes in driving conditions. These engineering constraints were addressed by coupling a battery to the fuel cell. A switching controller was designed and it was validated using realistic power profiles. Finally, a model reference adaptive controller was designed to handle nonlinearities and load transitions. The adaptive controller performance was enhanced by adding dead zone

  11. Durability of Low Platinum Fuel Cells Operating at High Power Density

    SciTech Connect

    Polevaya, Olga; Blanchet, Scott; Ahluwalia, Rajesh; Borup, Rod; Mukundan, Rangachary

    2014-03-19

    Understanding and improving the durability of cost-competitive fuel cell stacks is imperative to successful deployment of the technology. Stacks will need to operate well beyond today’s state-of-the-art rated power density with very low platinum loading in order to achieve the cost targets set forth by DOE ($15/kW) and ultimately be competitive with incumbent technologies. An accelerated cost-reduction path presented by Nuvera focused on substantially increasing power density to address non-PGM material costs as well as platinum. The study developed a practical understanding of the degradation mechanisms impacting durability of fuel cells with low platinum loading (≤0.2mg/cm2) operating at high power density (≥1.0W/cm2) and worked out approaches for improving the durability of low-loaded, high-power stack designs. Of specific interest is the impact of combining low platinum loading with high power density operation, as this offers the best chance of achieving long-term cost targets. A design-of-experiments approach was utilized to reveal and quantify the sensitivity of durability-critical material properties to high current density at two levels of platinum loading (the more conventional 0.45 mgPt.cm–1 and the much lower 0.2 mgPt.cm–2) across several cell architectures. We studied the relevance of selected component accelerated stress tests (AST) to fuel cell operation in power producing mode. New stress tests (NST) were designed to investigate the sensitivity to the addition of electrical current on the ASTs, along with combined humidity and load cycles and, eventually, relate to the combined city/highway drive cycle. Changes in the cathode electrochemical surface area (ECSA) and average oxygen partial pressure on the catalyst layer with aging under AST and NST protocols were compared based on the number of completed cycles. Studies showed elevated sensitivity of Pt growth to the potential limits and the initial particle size distribution. The ECSA loss

  12. An Investigation to Resolve the Interaction Between Fuel Cell, Power Conditioning System and Application Loads

    SciTech Connect

    Sudip K. Mazumder

    2005-12-31

    Development of high-performance and durable solidoxide fuel cells (SOFCs) and a SOFC power-generating system requires knowledge of the feedback effects from the power-conditioning electronics and from application-electrical-power circuits that may pass through or excite the power-electronics subsystem (PES). Therefore, it is important to develop analytical models and methodologies, which can be used to investigate and mitigate the effects of the electrical feedbacks from the PES and the application loads (ALs) on the reliability and performance of SOFC systems for stationary and non-stationary applications. However, any such attempt to resolve the electrical impacts of the PES on the SOFC would be incomplete unless one utilizes a comprehensive analysis, which takes into account the interactions of SOFC, PES, balance-of-plant system (BOPS), and ALs as a whole. SOFCs respond quickly to changes in load and exhibit high part- and full-load efficiencies due to its rapid electrochemistry, which is not true for the thermal and mechanical time constants of the BOPS, where load-following time constants are, typically, several orders of magnitude higher. This dichotomy can affect the lifetime and durability of the SOFCSs and limit the applicability of SOFC systems for load-varying stationary and transportation applications. Furthermore, without validated analytical models and investigative design and optimization methodologies, realizations of cost-effective, reliable, and optimal PESs (and power-management controls), in particular, and SOFC systems, in general, are difficult. On the whole, the research effort can lead to (a) cost-constrained optimal PES design for high-performance SOFCS and high energy efficiency and power density, (b) effective SOFC power-system design, analyses, and optimization, and (c) controllers and modulation schemes for mitigation of electrical impacts and wider-stability margin and enhanced system efficiency.

  13. Power production and wastewater treatment simultaneously by dual-chamber microbial fuel cell technique.

    PubMed

    Izadi, Paniz; Rahimnejad, Mostafa; Ghoreyshi, Ali

    2015-01-01

    Microbial fuel cell (MFC) is a novel technology that is able to convert the chemical energy of organic and inorganic substrates to electrical energy directly. The use of fossil fuels and recent energy crisis bring increasing attention to this technology. Besides electricity generation, wastewater treatment is another application of MFCs. Sulfide is a hazardous ion that is common in wastes. In this article, dual-chamber MFC was fabricated and a mixed culture of microorganisms was used as an active biocatalyst in an anaerobic anodic chamber to convert substrate to electricity. The obtained experimental results indicate that this MFC can successfully alter sulfide to elementary sulfur and power generation. The initial concentration of sulfide in wastewater was 1.5 g L(-1) , and it was removed after 10 days of MFC operation. Maximum produced power and current density were 48.68 mW⋅m(-2) and 231.47 mA⋅m(-2) , respectively. Besides, the influences of a biocathode were investigated and accordingly the data obtained for power and current density were increased to 372.27 mW⋅m(-2) and 1,665.15 mA⋅m(-2) , respectively. PMID:25640146

  14. A high power density miniaturized microbial fuel cell having carbon nanotube anodes

    NASA Astrophysics Data System (ADS)

    Ren, Hao; Pyo, Soonjae; Lee, Jae-Ik; Park, Tae-Jin; Gittleson, Forrest S.; Leung, Frederick C. C.; Kim, Jongbaeg; Taylor, André D.; Lee, Hyung-Sool; Chae, Junseok

    2015-01-01

    Microbial fuel cells (MFCs) are a promising technology capable of directly converting the abundant biomass on the planet into electricity. Prior studies have adopted a variety of nanostructured materials with high surface area to volume ratio (SAV), yet the current and power density of these nanostructured materials do not deliver a significant leap over conventional MFCs. This study presents a novel approach to implement a miniaturized MFC with a high SAV of 4000 m-1 using three different CNT-based electrode materials: Vertically Aligned CNT (VACNT), Randomly Aligned CNT (RACNT), and Spin-Spray Layer-by-Layer (SSLbL) CNT. These CNT-based electrodes show unique biofilm morphology and thickness. The study of performance parameters of miniaturized MFCs with these CNT-electrodes are conducted with respect to a control bare gold electrode. The results show that CNT-based materials attract more exoelectrogens, Geobacter sp., than bare gold, yielding thicker biofilm formation. Among CNT-based electrodes, low sheet resistance electrodes result in thick biofilm generation and high current/power density. The miniaturized MFC having an SSLbL CNT anode exhibits a high volumetric power density of 3320 W m-3. This research may help lay the foundation for future research involving the optimization of MFCS with 2D and 3D nanostructured electrodes.

  15. Aggrandizing power output from Shewanella oneidensis MR-1 microbial fuel cells using calcium chloride.

    PubMed

    Fitzgerald, Lisa A; Petersen, Emily R; Gross, Benjamin J; Soto, Carissa M; Ringeisen, Bradley R; El-Naggar, Mohamed Y; Biffinger, Justin C

    2012-01-15

    There are several interconnected metabolic pathways in bacteria essential for the conversion of carbon electron sources directly into electrical currents using microbial fuel cells (MFCs). This study establishes a direct exogenous method to increase power output from a Shewanella oneidensis MR-1 containing MFC by adding calcium chloride to the culture medium. The current output from each CaCl(2) concentration tested revealed that the addition of CaCl(2) to 1400 μM increased the current density by >80% (0.95-1.76 μA/cm(2)) using sodium lactate as the sole carbon source. Furthermore, polarization curves showed that the maximum power output could be increased from 157 to 330 μW with the addition of 2080 μM CaCl(2). Since the conductivity of the culture medium did not change after the addition of CaCl(2) (confirmed by EIS and bulk conductivity measurements), this increase in power was primarily biological and not based on ionic effects. Thus, controlling the concentration of CaCl(2) is a pathway to increase the efficiency and performance of S. oneidensis MR-1 MFCs. PMID:22154401

  16. Independent Orbiter Assessment (IOA): Analysis of the electrical power generation/fuel cell powerplant subsystem

    NASA Technical Reports Server (NTRS)

    Brown, K. L.; Bertsch, P. J.

    1986-01-01

    Results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA approach features a top-down analysis of the hardware to determine failure modes, criticality, and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. This report documents the independent analysis results corresponding to the Orbiter Electrical Power Generation (EPG)/Fuel Cell Powerplant (FCP) hardware. The EPG/FCP hardware is required for performing functions of electrical power generation and product water distribution in the Orbiter. Specifically, the EPG/FCP hardware consists of the following divisions: (1) Power Section Assembly (PSA); (2) Reactant Control Subsystem (RCS); (3) Thermal Control Subsystem (TCS); and (4) Water Removal Subsystem (WRS). The IOA analysis process utilized available EPG/FCP hardware drawings and schematics for defining hardware assemblies, components, and hardware items. Each level of hardware was evaluated and analyzed for possible failure modes and effects. Criticality was assigned based upon the severity of the effect for each failure mode.

  17. A novel self-powered and sensitive label-free DNA biosensor in microbial fuel cell.

    PubMed

    Asghary, Maryam; Raoof, Jahan Bakhsh; Rahimnejad, Mostafa; Ojani, Reza

    2016-08-15

    In this work, a novel self-powered, sensitive, low-cost, and label-free DNA biosensor is reported by applying a two-chambered microbial fuel cell (MFC) as a power supply. A graphite electrode and an Au nanoparticles modified graphite electrode (AuNP/graphite electrode) were used as anode and cathode in the MFC system, respectively. The active biocatalyst in the anodic chamber was a mixed culture of microorganisms. The sensing element of the biosensor was fabricated by the well-known Au-thiol binding the ssDNA probe on the surface of an AuNP/graphite cathode. Electrons produced by microorganisms were transported from the anode to the cathode through an external circuit, which could be detected by the terminal multi-meter detector. The difference between power densities of the ssDNA probe modified cathode in the absence and presence of complementary sequence served as the detection signal of the DNA hybridization with detection limit of 3.1nM. Thereafter, this biosensor was employed for diagnosis and determination of complementary sequence in a human serum sample. The hybridization specificity studies further revealed that the developed DNA biosensor could distinguish fully complementary sequences from one-base mismatched and non-complementary sequences. PMID:27085948

  18. Increased power generation from primary sludge by a submersible microbial fuel cell and optimum operational conditions.

    PubMed

    Vologni, Valentina; Kakarla, Ramesh; Angelidaki, Irini; Min, Booki

    2013-05-01

    Microbial fuel cells (MFCs) have received attention as a promising renewable energy technology for waste treatment and energy recovery. We tested a submersible MFC with an innovative design capable of generating a stable voltage of 0.250 ± 0.008 V (with a fixed 470 Ω resistor) directly from primary sludge. In a polarization test, the maximum power density was 0.18 W/m(2) at a current density of 0.8 A/m(2) with an external resistor of 300 Ω. The anodic solution of the primary sludge needs to be adjusted to a pH 7 for high power generation. The modified primary sludge with an added phosphate buffer prolonged the current generation and increased the power density by 7 and 1.5 times, respectively, in comparison with raw primary sludge. These findings suggest that energy recovery from primary sludge can be maximized using an advanced MFC system with optimum conditions. PMID:23420478

  19. Effect of C/N ratio and salinity on power generation in compost microbial fuel cells.

    PubMed

    Md Khudzari, Jauharah; Tartakovsky, Boris; Raghavan, G S Vijaya

    2016-02-01

    In this work, compost Microbial Fuel Cells (cMFCs) were used to generate electricity from a mix of fruit and vegetable wastes, and soil with different C/N ratios and salinities. Experiments were carried out in 500mL cMFCs equipped with carbon felt anodes and manganese dioxide cathodes. The cMFCs were loaded with fresh compost and operated at 20-23°C for up to 97days. The low C/N ratio (C/N 24) had a greater power production with a maximum power density of 5.29mW/m(2) (71.43mW/m(3)), indicating a more favorable condition for microbial growth. High-saline cMFCs produced lower power, suggesting that their level of salinity (10g/L of NaCl) inhibited electricigenic microorganisms. The closed-circuit cMFC showed an improved degradation of organic matter by 6% to 8% compared to the control MFC operated in an open circuit mode (no external resistor attached). PMID:26611399

  20. Recycled tire crumb rubber anodes for sustainable power production in microbial fuel cells

    NASA Astrophysics Data System (ADS)

    Wang, Heming; Davidson, Matthew; Zuo, Yi; Ren, Zhiyong

    One of the greatest challenges facing microbial fuel cells (MFCs) in large scale applications is the high cost of electrode material. We demonstrate here that recycled tire crumb rubber coated with graphite paint can be used instead of fine carbon materials as the MFC anode. The tire particles showed satisfactory conductivity after 2-4 layers of coating. The specific surface area of the coated rubber was over an order of magnitude greater than similar sized graphite granules. Power production in single chamber tire-anode air-cathode MFCs reached a maximum power density of 421 mW m -2, with a coulombic efficiency (CE) of 25.1%. The control graphite granule MFC achieved higher power density (528 mW m -2) but lower CE (15.6%). The light weight of tire particle could reduce clogging and maintenance cost but posts challenges in conductive connection. The use of recycled material as the MFC anodes brings a new perspective to MFC design and application and carries significant economic and environmental benefit potentials.

  1. The modeling of a standalone solid-oxide fuel cell auxiliary power unit

    NASA Astrophysics Data System (ADS)

    Lu, N.; Li, Q.; Sun, X.; Khaleel, M. A.

    In this research, a Simulink model of a standalone vehicular solid-oxide fuel cell (SOFC) auxiliary power unit (APU) is developed. The SOFC APU model consists of three major components: a controller model; a power electronics system model; and an SOFC plant model, including an SOFC stack module, two heat exchanger modules, and a combustor module. This paper discusses the development of the nonlinear dynamic models for the SOFC stacks, the heat exchangers and the combustors. When coupling with a controller model and a power electronic circuit model, the developed SOFC plant model is able to model the thermal dynamics and the electrochemical dynamics inside the SOFC APU components, as well as the transient responses to the electric loading changes. It has been shown that having such a model for the SOFC APU will help design engineers to adjust design parameters to optimize the performance. The modeling results of the SOFC APU heat-up stage and the output voltage response to a sudden load change are presented in this paper. The fuel flow regulation based on fuel utilization is also briefly discussed.

  2. Fuel Cell Demonstration Project - 200 kW - Phosphoric Acid Fuel Cell Power Plant Located at the National Transportation Research Center: FINAL REPORT

    SciTech Connect

    Berry, JB

    2005-05-06

    Oak Ridge National Laboratory (ORNL) researches and develops distributed generation technology for the Department of Energy, Energy Efficiency and Renewable Energy Distributed Energy Program. This report describes installation and operation of one such distributed generation system, a United Technology Corporation fuel cell located at the National Transportation Research Center in Knoxville, Tennessee. Data collected from June 2003 to June of 2004, provides valuable insight regarding fuel cell-grid compatibility and the cost-benefit of the fuel cell operation. The NTRC fuel cell included a high-heat recovery option so that use of thermal energy improves project economics and improves system efficiency to 59% year round. During the year the fuel cell supplied a total of 834MWh to the NTRC and provided 300MBtu of hot water. Installation of the NTRC fuel cell was funded by the Distributed Energy Program with partial funding from the Department of Defense's Climate Change Fuel Cell Buy Down Program, administered by the National Energy Technology Laboratory. On-going operational expenses are funded by ORNL's utility budget and are paid from operational cost savings. Technical information and the benefit-cost of the fuel cell are both evaluated in this report and sister reports.

  3. A review of high-temperature polymer electrolyte membrane fuel-cell (HT-PEMFC)-based auxiliary power units for diesel-powered road vehicles

    NASA Astrophysics Data System (ADS)

    Liu, Yongfeng; Lehnert, Werner; Janßen, Holger; Samsun, Remzi Can; Stolten, Detlef

    2016-04-01

    This paper presents an extensive review of research on the development of auxiliary power units with enhanced reformate tolerance for high temperature polymer electrolyte membrane fuel cells (HT-PEMFCs). Developments in diesel reforming for fuel cells as auxiliary power units (APUs), single fuel cells and stacks and systems are outlined in detail and key findings are presented. Summaries of HT-PEMFC APU applications and start-up times for HT-PEMFC systems are then given. A summary of cooling HT-PEMFC stacks using a classic schematic diagram of a 24-cell HT-PEMFC stack, with a cooling plate for every third cell, is also presented as part of a stack analysis. Finally, a summary of CO tolerances for fuel cells is given, along with the effects of different CO volume fractions on polarization curves, the fraction of CO coverage, hydrogen coverage, anode overpotential and cell potential.

  4. Utility experience with a 250-kW molten carbonate fuel cell cogeneration power plant at NAS Miramar, San Diego

    NASA Astrophysics Data System (ADS)

    Figueroa, R. A.; Otahal, J.

    This paper focuses on the strategy and experience of San Diego Gas and Electric with the development and demonstration of a proof of concept 250-kW internally manifolded heat exchanger (IMHEX®) carbonate fuel cell power plant. The plant was installed, commissioned, and operated by San Diego Gas and Electric (SDG&E) in a cogeneration mode at the Naval Air Station (NAS) at Miramar in San Diego. These activities were part of a collaborative effort between SDG&E and M-C Power's Program team (IMHEX® Team). The IMHEX® Team consists of M-C Power, Bechtel Engineering, Stewart and Stevenson, and the Institute of Gas Technology (IGT). The technical aspects of the plant's commissioning and operation were addressed by my colleague, J. Otahal, in a poster presentation. Our activities in carbonate fuel cell development are unique because of the level of involvement by an investor-owned utility in the development, engineering, installation, operation and maintenance of a fuel cell demonstration plant. The following topics are discussed in this paper: (i) SDG&E's involvement in the development of molten carbonate fuel cell (MCFC) technology; (ii) the active role in engineering and specification of the IMHEX® MCFC demonstration plant; (iii) responsibility for installation, commissioning, and operation; (iv) utility role in technology development and application of MCFC in a restructured and competitive environment; (v) summary.

  5. Development of a Soldier-Portable Fuel Cell Power System, Part I: A Bread-Board Methanol Fuel Processor

    SciTech Connect

    Palo, Daniel R.; Holladay, Jamelyn D.; Rozmiarek, Robert T.; Guzman-Leong, Consuelo E.; Wang, Yong; Hu, Jianli; Chin, Ya-Huei; Dagle, Robert A.; Baker, Eddie G.

    2002-06-01

    A 15-We portable power system is being developed for the US Army, comprised of a hydrogen-generating fuel reformer coupled to a hydrogen-converting fuel cell. As a first phase of this project, a methanol steam reformer system was developed and demonstrated. The reformer system included a combustor, two vaporizers, and a steam-reforming reactor. The device was demonstrated as a thermally independent unit over the range of 14 to 80 Wt output. Assuming a 14-day mission life and an ultimate 1-kg fuel processor/fuel cell assembly, a base case was chosen to illustrate the expected system performance. Operating at 13 We, the system yielded a fuel processor efficiency of 45% (LHV of H2 out/LHV of fuel in) and an estimated net efficiency of 22% (assuming a fuel cell efficiency of 48%). The resulting energy density of 720 W-hr/kg is several times the energy density of the best lithium-ion batteries. Some immediate areas of improvement in thermal management also have been identified and an integrated fuel processor is under development. The final system will be a hybrid, containing a fuel reformer, fuel cell, and rechargeable battery. The battery will provide power for startup and added capacity for times of peak power demand.

  6. Fuel cell generator energy dissipator

    DOEpatents

    Veyo, Stephen Emery; Dederer, Jeffrey Todd; Gordon, John Thomas; Shockling, Larry Anthony

    2000-01-01

    An apparatus and method are disclosed for eliminating the chemical energy of fuel remaining in a fuel cell generator when the electrical power output of the fuel cell generator is terminated. During a generator shut down condition, electrically resistive elements are automatically connected across the fuel cell generator terminals in order to draw current, thereby depleting the fuel

  7. High power density microbial fuel cell with flexible 3D graphene-nickel foam as anode

    NASA Astrophysics Data System (ADS)

    Wang, Hanyu; Wang, Gongming; Ling, Yichuan; Qian, Fang; Song, Yang; Lu, Xihong; Chen, Shaowei; Tong, Yexiang; Li, Yat

    2013-10-01

    The structure and electrical conductivity of anode play a significant role in the power generation of microbial fuel cells (MFCs). In this study, we developed a three-dimensional (3D) reduced graphene oxide-nickel (denoted as rGO-Ni) foam as an anode for MFC through controlled deposition of rGO sheets onto the nickel foam substrate. The loading amount of rGO sheets and electrode surface area can be controlled by the number of rGO loading cycles. 3D rGO-Ni foam anode provides not only a large accessible surface area for microbial colonization and electron mediators, but also a uniform macro-porous scaffold for effective mass diffusion of the culture medium. Significantly, at a steady state of the power generation, the MFC device with flexible rGO-Ni electrodes produced an optimal volumetric power density of 661 W m-3 calculated based on the volume of anode material, or 27 W m-3 based on the volume of the anode chamber. These values are substantially higher than that of plain nickel foam, and other conventional carbon based electrodes (e.g., carbon cloth, carbon felt, and carbon paper) measured in the same conditions. To our knowledge, this is the highest volumetric power density reported for mL-scale MFC device with a pure strain of Shewanella oneidensis MR-1. We also demonstrated that the MFC device can be operated effectively in a batch-mode at least for a week. These new 3D rGO-Ni electrodes show great promise for improving the power generation of MFC devices.The structure and electrical conductivity of anode play a significant role in the power generation of microbial fuel cells (MFCs). In this study, we developed a three-dimensional (3D) reduced graphene oxide-nickel (denoted as rGO-Ni) foam as an anode for MFC through controlled deposition of rGO sheets onto the nickel foam substrate. The loading amount of rGO sheets and electrode surface area can be controlled by the number of rGO loading cycles. 3D rGO-Ni foam anode provides not only a large accessible

  8. Power generation using carbon mesh cathodes with different diffusion layers in microbial fuel cells

    NASA Astrophysics Data System (ADS)

    Luo, Yong; Zhang, Fang; Wei, Bin; Liu, Guangli; Zhang, Renduo; Logan, Bruce E.

    An inexpensive carbon material, carbon mesh, was examined to replace the more expensive carbon cloth usually used to make cathodes in air-cathode microbial fuel cells (MFCs). Three different diffusion layers were tested using carbon mesh: poly(dimethylsiloxane) (PDMS), polytetrafluoroethylene (PTFE), and Goretex cloth. Carbon mesh with a mixture of PDMS and carbon black as a diffusion layer produced a maximum power density of 1355 ± 62 mW m -2 (normalized to the projected cathode area), which was similar to that obtained with a carbon cloth cathode (1390 ± 72 mW m -2). Carbon mesh with a PTFE diffusion layer produced only a slightly lower (6.6%) maximum power density (1303 ± 48 mW m -2). The Coulombic efficiencies were a function of current density, with the highest value for the carbon mesh and PDMS (79%) larger than that for carbon cloth (63%). The cost of the carbon mesh cathode with PDMS/Carbon or PTFE (excluding catalyst and binder costs) is only 2.5% of the cost of the carbon cloth cathode. These results show that low cost carbon materials such as carbon mesh can be used as the cathode in an MFC without reducing the performance compared to more expensive carbon cloth.

  9. Reliability and availability analysis of low power portable direct methanol fuel cells

    NASA Astrophysics Data System (ADS)

    Sisworahardjo, N. S.; Alam, M. S.; Aydinli, G.

    This paper presents a methodology for modeling and calculating the reliability and availability of low power portable direct methanol fuel cells (DMFCs). System reliability and availability are critical factors for improving market acceptance and for determining the competitiveness of the low power DMFC. Two techniques have been used for analyzing the system reliability and availability requirements for various system components. Reliability block diagram (RBD) is formed based on the failure rates of irreparable system components. A state-space method is developed to calculate system availability using the Markov model (MM). The state-space method incorporates three different states-operational, derated, and fully faulted states. Since most system components spend their lifetime in performing normal functional task, this research is focused mainly on this operational period. The failure and repair rates for repairable DMFC systems are estimated on the basis of a homogeneous Poisson process (HPP) and exponential distribution. Extensive analytical modeling and simulation study has been performed to verify the effectiveness of the proposed technique.

  10. Engine-integrated solid oxide fuel cells for efficient electrical power generation on aircraft

    NASA Astrophysics Data System (ADS)

    Waters, Daniel F.; Cadou, Christopher P.

    2015-06-01

    This work investigates the use of engine-integrated catalytic partial oxidation (CPOx) reactors and solid oxide fuel cells (SOFCs) to reduce fuel burn in vehicles with large electrical loads like sensor-laden unmanned air vehicles. Thermodynamic models of SOFCs, CPOx reactors, and three gas turbine (GT) engine types (turbojet, combined exhaust turbofan, separate exhaust turbofan) are developed and checked against relevant data and source material. Fuel efficiency is increased by 4% and 8% in the 50 kW and 90 kW separate exhaust turbofan systems respectively at only modest cost in specific power (8% and 13% reductions respectively). Similar results are achieved in other engine types. An additional benefit of hybridization is the ability to provide more electric power (factors of 3 or more in some cases) than generator-based systems before encountering turbine inlet temperature limits. A sensitivity analysis shows that the most important parameters affecting the system's performance are operating voltage, percent fuel oxidation, and SOFC assembly air flows. Taken together, this study shows that it is possible to create a GT-SOFC hybrid where the GT mitigates balance of plant losses and the SOFC raises overall system efficiency. The result is a synergistic system with better overall performance than stand-alone components.

  11. Integrating engineering design improvements with exoelectrogen enrichmentprocess to increase power output from microbial fuel cells

    SciTech Connect

    Borole, Abhijeet P; Hamilton, Choo Yieng; Vishnivetskaya, Tatiana A; Leak, David; Andras, Calin; Morrell-Falvey, Jennifer L; Keller, Martin; Davison, Brian H

    2009-01-01

    Microbial fuel cells (MFC) hold promise as a green technology for bioenergy production. The challenge is to improve the engineering design while exploiting the ability of microbes to generate and transfer electrons directly to electrodes. A strategy using a combination of improved anode design and an enrichment processwas formulated to improve power densities. The designwas based on a flow-through anode with minimal dead volume and a high electrode surface area per unit volume. The strategy focused on promoting biofilm formation via a combination of forced flow through the anode, carbon limitation, and step-wise reduction of external resistance. The enrichment process resulted in development of exoelectrogenic biofilm communities dominated by Anaeromusa spp. This is the first report identifying organisms fromthe Veillonellaceae family in MFCs. The power density of the resulting MFC using a ferricyanide cathode reached 300Wm−3 net anode volume (3220mWm−2), which is about a third of what is estimated to be necessary for commercial consideration. The operational stability of the MFC using high specific surface area electrodes was demonstrated by operating the MFC for a period of over four months.

  12. Effects of wind-powered hydrogen fuel cell vehicles on stratospheric ozone and global climate

    NASA Astrophysics Data System (ADS)

    Jacobson, Mark Z.

    2008-10-01

    Converting the world's fossil-fuel onroad vehicles (FFOV) to hydrogen fuel cell vehicles (HFCV), where the H2 is produced by wind-powered electrolysis, is estimated to reduce global fossil, biofuel, and biomass-burning emissions of CO2 by ~13.4%, NOx ~23.0%, nonmethane organic gases ~18.9%, black carbon ~8% H2 ~3.2% (at 3% leakage), and H2O ~0.2%. Over 10 years, such reductions were calculated to reduce tropospheric CO ~5%, NOx ~5-13%, most organic gases ~3-15%, OH ~4%, ozone ~6%, and PAN ~13%, but to increase tropospheric CH4 ~0.25% due to the lower OH. Lower OH also increased upper tropospheric/lower stratospheric ozone, increasing its global column by ~0.41%. WHFCV cooled the troposphere and warmed the stratosphere, reduced aerosol and cloud surface areas, and increased precipitation. Other renewable-powered HFCV or battery electric vehicles should have similar impacts.

  13. Power generation by packed-bed air-cathode microbial fuel cells.

    PubMed

    Zhang, Xiaoyuan; Shi, Juan; Liang, Peng; Wei, Jincheng; Huang, Xia; Zhang, Chuanyi; Logan, Bruce E

    2013-08-01

    Catalysts and catalyst binders are significant portions of the cost of microbial fuel cell (MFC) cathodes. Many materials have been tested as aqueous cathodes, but air-cathodes are needed to avoid energy demands for water aeration. Packed-bed air-cathodes were constructed without expensive binders or diffusion layers using four inexpensive carbon-based materials. Cathodes made from activated carbon produced the largest maximum power density of 676 ± 93 mW/m(2), followed by semi-coke (376 ± 47 mW/m(2)), graphite (122 ± 14 mW/m(2)) and carbon felt (60 ± 43 mW/m(2)). Increasing the mass of activated carbon and semi-coke from 5 to ≥ 15 g significantly reduced power generation because of a reduction in oxygen transfer due to a thicker water layer in the cathode (∼3 or ∼6 cm). These results indicate that a thin packed layer of activated carbon or semi-coke can be used to make inexpensive air-cathodes for MFCs. PMID:23732924

  14. Self-stacked submersible microbial fuel cell (SSMFC) for improved remote power generation from lake sediments.

    PubMed

    Zhang, Yifeng; Angelidaki, Irini

    2012-05-15

    Electric energy can be harvested from aquatic sediments by utilizing microbial fuel cells (MFCs). A main challenge of this application is the limited voltage output. In this study, an innovative self-stacked submersible MFC (SSMFC) was developed to improve the voltage generation from lake sediments. The SSMFC successfully produced a maximum power density of 294 mW/m(2) and had an open circuit voltage (OCV) of 1.12 V. However, voltage reversal was observed in one cell at high current density. Investigation on the cause for voltage reversal revealed that voltage reversal was occurring only when low external resistance (≤ 400Ω in this study) was applied. In addition, the internal resistance and OCV were the most important parameters for predicting which cell unit had the highest probability to undergo voltage reversal. Use of a capacitor was found to be an effective way to prevent voltage reversal and at the same time store power. These results provide new insight into the development of effective MFC system, capable of extracting energy and promoting bioremediation of organic pollutants from sediments. PMID:22436687

  15. A Carbon-Neutral Photosynthetic Microbial Fuel Cell Powered by Microcystis aeruginosa.

    PubMed

    Ma, Meirong; Cao, Limin; Chen, Li; Ying, Xiaofang; Deng, Zongwu

    2015-07-01

    A photosynthetic microbial fuel cell (m-PMFC) is developed for generating electricity by harnessing solar energy using Microcystis aeruginosa. In this m-PMFC, commensal bacteria can consume the nutrients that Microcystis aeruginosa produces to generate electricity so that no net CO₂production occurs. A b-MFC is constructed to confirm the role of commensal bacteria in electric generation. An s-PMFC is constructed to confirm the contribution of Microcystis aeruginosa as substrates. The power outputs of m-PMFCs exhibit no significant difference in terms of different inoculation amount of Microcystis aeruginosa or light/dark cycles. The power density of m-PMFC exhibits similar response to bubbling of N₂and O₂as that of b-MFC, as confirmed by cyclic voltammetry analysis of m-PMFC and b-MFC. Scanning electron microscope images demonstrate that the biofilm of m-PMFC consists mainly of commensal bacteria. These results suggest that commensal bacteria act as the main biocatalysts and Microcystis aeruginosa as the anode substrates in the m-PMFC. PMID:26163500

  16. Self-powered denitration of landfill leachate through ammonia/nitrate coupled redox fuel cell reactor.

    PubMed

    Zhang, Huimin; Xu, Wei; Feng, Daolun; Liu, Zhanmeng; Wu, Zucheng

    2016-03-01

    In order to explore the feasibility of energy-free denitrifying N-rich wastewater, a self-powered device was uniquely assembled, in which ammonia/nitrate coupled redox fuel cell (CRFC) reactor was served as removing nitrogen and harvesting electric energy simultaneously. Ammonia is oxidized at anodic compartment and nitrate is reduced at cathodic compartment spontaneously by electrocatalysis. In 7.14 mM ammonia+0.2M KOH anolyte and 4.29 mM KNO3+0.1M H2SO4 catholyte, the nitrate removal efficiency was 46.9% after 18 h. Meanwhile, a maximum power density of 170 mW m(-2) was achieved when applying Pd/C cathode. When NH4Cl/nitrate and ammonia/nitrite CRFCs were tested, 26.2% N-NH4Cl and 91.4% N-NO2(-) were removed respectively. Nitrogen removal efficiency for real leachate at the same initial NH3-N concentration is 22.9% and nitrification of ammonia in leachate can be used as nitrate source. This work demonstrated a new way for N-rich wastewater remediation with electricity generation. PMID:26720140

  17. Study of a small heat and power PEM fuel cell system generator

    NASA Astrophysics Data System (ADS)

    Hubert, Charles-Emile; Achard, Patrick; Metkemeijer, Rudolf

    A micro-cogenerator based on a natural gas reformer and a PEMFC is studied in its entirety, pointing out the links between different sub-systems. The study is conducted within the EPACOP project, which aims at testing PEMFC systems on user sites to evaluate development and acceptance of this technology for small stationary applications. Five units were installed from November 2002 to May 2003 and have been operated until now, in real life conditions. They deliver up to 4 kW of AC power and about 6 kW of heat. Center for Energy and Processes (CEP), one of the scientific partners, processes and analyses the experimental data from the five units, running in different regions of France. This database and the study of the flowsheet enable to propose changes to enhance the efficiency of the system composed of a steam reforming, a shift and a preferential oxidation reactor, a fuel cell stack and heat exchangers. The steady state modelling and optimisation of the system is done with Thermoptim ®, a software developed within CEP for applied thermodynamics. At constant power, main targets are to decrease natural gas consumption, to increase heat recovery and to improve the water balance. This study is made using the pinch point analysis, at full load and partial load. Main results of this study are different system configurations that allow improvement of gross electrical and thermal efficiency and enable to obtain a positive water balance.

  18. Simulated coal-gas fueled carbonate fuel cell power plant system verification. Final report, September 1990--June 1995

    SciTech Connect

    1995-03-01

    This report summarizes work performed under U.S. Department of Energy, Morgantown Energy Technology Center (DOE/METC) Contract DE-AC-90MC27168 for September 1990 through March 1995. Energy Research Corporation (ERC), with support from DOE, EPRI, and utilities, has been developing a carbonate fuel cell technology. ERC`s design is a unique direct fuel cell (DFC) which does not need an external fuel reformer. An alliance was formed with a representative group of utilities and, with their input, a commercial entry product was chosen. The first 2 MW demonstration unit was planned and construction begun at Santa Clara, CA. A conceptual design of a 10OMW-Class dual fuel power plant was developed; economics of natural gas versus coal gas use were analyzed. A facility was set up to manufacture 2 MW/yr of carbonate fuel cell stacks. A 100kW-Class subscale power plant was built and several stacks were tested. This power plant has achieved an efficiency of {approximately}50% (LHV) from pipeline natural gas to direct current electricity conversion. Over 6,000 hours of operation including 5,000 cumulative hours of stack operation were demonstrated. One stack was operated on natural gas at 130 kW, which is the highest carbonate fuel cell power produced to date, at 74% fuel utilization, with excellent performance distribution across the stack. In parallel, carbonate fuel cell performance has been improved, component materials have been proven stable with lifetimes projected to 40,000 hours. Matrix strength, electrolyte distribution, and cell decay rate have been improved. Major progress has been achieved in lowering stack cost.

  19. Removal of sulphur-containing odorants from fuel gases for fuel cell-based combined heat and power applications

    NASA Astrophysics Data System (ADS)

    de Wild, P. J.; Nyqvist, R. G.; de Bruijn, F. A.; Stobbe, E. R.

    Natural gas (NG) and liquefied petroleum gas (LPG) are important potential feedstocks for the production of hydrogen for fuel cell-based (e.g. proton exchange membrane fuel cells (PEMFC) or solid oxide fuel Cells (SOFC) combined heat and power (CHP) applications. To prevent detrimental effects on the (electro)catalysts in fuel cell-based combined heat and power installations (FC-CHP), sulphur removal from the feedstock is mandatory. An experimental bench-marking study of adsorbents has identified several candidates for the removal of sulphur containing odorants at low temperature. Among these adsorbents a new material has been discovered that offers an economically attractive means to remove TetraHydroThiophene (THT), the main European odorant, from natural gas at ambient temperature. The material is environmentally benign, easy to use and possesses good activity (residual sulphur levels below 20 ppbv) and capacity for the common odorant THT in natural gas. When compared to state-of-the-art metal-promoted active carbon the new material has a THT uptake capacity that is up to 10 times larger, depending on temperature and pressure. Promoted versions of the new material have shown potential for the removal of THT at higher temperatures and/or for the removal of other odorants such as mercaptans from natural gas or from LPG.

  20. "Dedicated To The Continued Education, Training and Demonstration of PEM Fuel Cell Powered Lift Trucks In Real-World Applications."

    SciTech Connect

    Dever, Thomas J.

    2011-11-29

    The project objective was to further assist in the commercialization of fuel cell and H2 technology by building further upon the successful fuel cell lift truck deployments that were executed by LiftOne in 2007, with longer deployments of this technology in real-world applications. We involved facilities management, operators, maintenance personnel, safety groups, and Authorities Having Jurisdiction. LiftOne strived to educate a broad group from many areas of industry and the community as to the benefits of this technology. Included were First Responders from the local areas. We conducted month long deployments with end-users to validate the value proposition and the market requirements for fuel cell powered lift trucks. Management, lift truck operators, Authorities Having Jurisdiction and the general public experienced 'hands on' fuel cell experience in the material handling applications. We partnered with Hydrogenics in the execution of the deployment segment of the program. Air Products supplied the compressed H2 gas and the mobile fueler. Data from the Fuel Cell Power Packs and the mobile fueler was sent to the DOE and NREL as required. Also, LiftOne conducted the H2 Education Seminars on a rotating basis at their locations for lift trucks users and for other selected segments of the community over the project's 36 month duration. Executive Summary The technology employed during the deployments program was not new, as the equipment had been used in several previous demos and early adoptions within the material handling industry. This was the case with the new HyPx Series PEM - Fuel Cell Power Packs used, which had been demo'd before during the 2007 Greater Columbia Fuel Cell Challenge. The Air Products HF-150 Fueler was used outdoors during the deployments and had similarly been used for many previous demo programs. The methods used centered on providing this technology as the power for electric sit-down lift trucks at high profile companies operating large

  1. Flowsheet calculation of a combined heat and power fuel cell plant with a conceptual molten carbonate fuel cell with separate CO 2 supply

    NASA Astrophysics Data System (ADS)

    Au, S. F.; Hemmes, K.; Woudstra, N.

    A new type of MCFC with a separate CO 2 supply (improved or i-MCFC) is previously presented, which has the potential for reducing NiO cathode dissolution and system enhancement by CO 2 removal from fuel gas. This article presents the first flowsheet calculations of an i-MCFC system that utilizes the potential of reducing NiO dissolution. A submodel that simulates energy and massflows of the i-MCFC is built using standard flowsheeting components. The performance of the i-MCFC is assumed to be equal to the MCFC and differences in Nernst potentials and irreversible losses are neglected. To compare the differences in concept, a MCFC combined heat and power (CHP) system flowsheet is modified and the MCFC model substituted by the i-MCFC submodel. The overall efficiencies of both fuel cell systems are calculated using a flowsheeting program. The calculated results are compared and the differences analyzed. The overall system performance of this i-MCFC CHP system is slightly lower than the MCFC CHP reference system (about 0.1% point in average). The difference in performance is ascribed to the change in gas composition and heat capacity of the cathode gas. The change in heat capacity increases the total massflow through the i-MCFC resulting to an increase in overall auxiliary power consumption. The low CO 2 content of the cathode gas should reduce the NiO cathode dissolution to a negligible level.

  2. Natural-gas-fueled molten carbonate fuel cell power plant development

    SciTech Connect

    Reiser, C.A. )

    1990-12-01

    The high temperature molten carbonate fuel cell (MCFC) operating on natural gas fuel offers an exceptional opportunity for providing economically competitive, high efficiency, low emissions power generators for utilities and industrial and commercial cogenerators. The primary goal of this project is to establish a path to develop competitive natural gas fueled MCFC products with goals of less than $1000 per kW and 6000 Btu/kWhr heat rate (based on higher heating value). A coal fueled MCFC system study funded by DOE under contract AC21-MC23270 was used as a basis to define natural gas fuel products with a high degree of commonality with the coal gas systems. In this way, the natural gas systems could be derived from the DOE coal-fueled system with a minimum of non-recurring cost. The effort was carried out in three technical tasks. Task 1, Conceptual System Design Studies -- provides a conceptual design definition of a multimegawatt power plant system adapted from DOE coal-gas/natural gas design data and provides a preliminary design definition of a truck and/or rail transportable, megawatt scale power plant derived from a DOE coal-gas/natural gas power unit; Task 2, Integrated System Test Design -- provides a preliminary design of a kW-scale integrated system to resolve critical component and system integration issues specific to the natural gas products defined in Task 1; and Task 3, Critical Element Evaluation -- provides the analytical and experimental assessments of the critical non-stack components identified in Tasks 1 and 2. 32 figs., 22 tabs.

  3. Enhanced current and power density of micro-scale microbial fuel cells with ultramicroelectrode anodes

    NASA Astrophysics Data System (ADS)

    Ren, Hao; Rangaswami, Sriram; Lee, Hyung-Sool; Chae, Junseok

    2016-09-01

    We present a micro-scale microbial fuel cell (MFC) with an ultramicroelectrode (UME) anode, with the aim of creating a miniaturized high-current/power-density converter using carbon-neutral and renewable energy sources. Micro-scale MFCs have been studied for more than a decade, yet their current and power densities are still an order of magnitude lower than those of their macro-scale counterparts. In order to enhance the current/power densities, we engineer a concentric ring-shaped UME, with a width of 20 μm, to facilitate the diffusion of ions in the vicinity of the micro-organisms that form biofilm on the UME. The biofilm extends approximately 15 μm from the edge of the UME, suggesting the effective biofilm area increases. Measured current/power densities per the effective area and the original anode area are 7.08  ±  0.01 A m‑2 & 3.09  ±  0.04 W m‑2 and 17.7  ±  0.03 A m‑2 & 7.72  ±  0.09 W m‑2, respectively. This is substantially higher than any prior work in micro-scale MFCs, and very close, or even higher, to that of macro-scale MFCs. A Coulombic efficiency, a measure of how efficiently an MFC harvests electrons from donor substrate, of 70%, and an energy conversion efficiency of 17% are marked, highlighting the micro-scale MFC as an attractive alternative within the existing energy conversion portfolio.

  4. Purge gas protected transportable pressurized fuel cell modules and their operation in a power plant

    DOEpatents

    Zafred, Paolo R.; Dederer, Jeffrey T.; Gillett, James E.; Basel, Richard A.; Antenucci, Annette B.

    1996-01-01

    A fuel cell generator apparatus and method of its operation involves: passing pressurized oxidant gas, (O) and pressurized fuel gas, (F), into fuel cell modules, (10 and 12), containing fuel cells, where the modules are each enclosed by a module housing (18), surrounded by an axially elongated pressure vessel (64), where there is a purge gas volume, (62), between the module housing and pressure vessel; passing pressurized purge gas, (P), through the purge gas volume, (62), to dilute any unreacted fuel gas from the modules; and passing exhaust gas, (82), and circulated purge gas and any unreacted fuel gas out of the pressure vessel; where the fuel cell generator apparatus is transpatable when the pressure vessel (64) is horizontally disposed, providing a low center of gravity.

  5. Optimal operation management of fuel cell/wind/photovoltaic power sources connected to distribution networks

    NASA Astrophysics Data System (ADS)

    Niknam, Taher; Kavousifard, Abdollah; Tabatabaei, Sajad; Aghaei, Jamshid

    2011-10-01

    In this paper a new multiobjective modified honey bee mating optimization (MHBMO) algorithm is presented to investigate the distribution feeder reconfiguration (DFR) problem considering renewable energy sources (RESs) (photovoltaics, fuel cell and wind energy) connected to the distribution network. The objective functions of the problem to be minimized are the electrical active power losses, the voltage deviations, the total electrical energy costs and the total emissions of RESs and substations. During the optimization process, the proposed algorithm finds a set of non-dominated (Pareto) optimal solutions which are stored in an external memory called repository. Since the objective functions investigated are not the same, a fuzzy clustering algorithm is utilized to handle the size of the repository in the specified limits. Moreover, a fuzzy-based decision maker is adopted to select the 'best' compromised solution among the non-dominated optimal solutions of multiobjective optimization problem. In order to see the feasibility and effectiveness of the proposed algorithm, two standard distribution test systems are used as case studies.

  6. Electricity and disinfectant production from wastewater: Microbial Fuel Cell as a self-powered electrolyser.

    PubMed

    Gajda, Iwona; Greenman, John; Melhuish, Chris; Ieropoulos, Ioannis A

    2016-01-01

    This study presents a simple and sustainable Microbial Fuel Cell as a standalone, self-powered reactor for in situ wastewater electrolysis, recovering nitrogen from wastewater. A process is proposed whereby the MFC electrical performance drives the electrolysis of wastewater towards the self-generation of catholyte within the same reactor. The MFCs were designed to harvest the generated catholyte in the internal chamber, which showed that liquid production rates are largely proportional to electrical current generation. The catholyte demonstrated bactericidal properties, compared to the control (open-circuit) diffusate, and reduced observable biofilm formation on the cathode electrode. Killing effects were confirmed using bacterial kill curves constructed by exposing a bioluminescent Escherichia coli target, as a surrogate coliform, to catholyte where a rapid kill rate was observed. Therefore, MFCs could serve as a water recovery system, a disinfectant/cleaner generator that limits undesired biofilm formation and as a washing agent in waterless urinals to improve sanitation. This simple and ready to implement MFC system can convert organic waste directly into electricity and self-driven nitrogen along with water recovery. This could lead to the development of energy positive bioprocesses for sustainable wastewater treatment. PMID:27172836

  7. Electricity and disinfectant production from wastewater: Microbial Fuel Cell as a self-powered electrolyser

    PubMed Central

    Gajda, Iwona; Greenman, John; Melhuish, Chris; Ieropoulos, Ioannis A.

    2016-01-01

    This study presents a simple and sustainable Microbial Fuel Cell as a standalone, self-powered reactor for in situ wastewater electrolysis, recovering nitrogen from wastewater. A process is proposed whereby the MFC electrical performance drives the electrolysis of wastewater towards the self-generation of catholyte within the same reactor. The MFCs were designed to harvest the generated catholyte in the internal chamber, which showed that liquid production rates are largely proportional to electrical current generation. The catholyte demonstrated bactericidal properties, compared to the control (open-circuit) diffusate, and reduced observable biofilm formation on the cathode electrode. Killing effects were confirmed using bacterial kill curves constructed by exposing a bioluminescent Escherichia coli target, as a surrogate coliform, to catholyte where a rapid kill rate was observed. Therefore, MFCs could serve as a water recovery system, a disinfectant/cleaner generator that limits undesired biofilm formation and as a washing agent in waterless urinals to improve sanitation. This simple and ready to implement MFC system can convert organic waste directly into electricity and self-driven nitrogen along with water recovery. This could lead to the development of energy positive bioprocesses for sustainable wastewater treatment. PMID:27172836

  8. Optimal operation management of fuel cell/wind/photovoltaic power sources connected to distribution networks

    NASA Astrophysics Data System (ADS)

    Niknam, Taher; Kavousifard, Abdollah; Tabatabaei, Sajad; Aghaei, Jamshid

    2011-10-01

    In this paper a new multiobjective modified honey bee mating optimization (MHBMO) algorithm is presented to investigate the distribution feeder reconfiguration (DFR) problem considering renewable energy sources (RESs) (photovoltaics, fuel cell and wind energy) connected to the distribution network. The objective functions of the problem to be minimized are the electrical active power losses, the voltage deviations, the total electrical energy costs and the total emissions of RESs and substations. During the optimization process, the proposed algorithm finds a set of non-dominated (Pareto) optimal solutions which are stored in an external memory called repository. Since the objective functions investigated are not the same, a fuzzy clustering algorithm is utilized to handle the size of the repository in the specified limits. Moreover, a fuzzy-based decision maker is adopted to select the ‘best' compromised solution among the non-dominated optimal solutions of multiobjective optimization problem. In order to see the feasibility and effectiveness of the proposed algorithm, two standard distribution test systems are used as case studies.

  9. The Case for Natural Gas Fueled Solid Oxide Fuel Cell Power Systems for Distributed Generation

    SciTech Connect

    Chick, Lawrence A.; Weimar, Mark R.; Whyatt, Greg A.; Powell, Michael R.

    2015-02-01

    Natural-gas-fueled solid oxide fuel cell (NGSOFC) power systems yield electrical conversion efficiencies exceeding 60% and may become a viable alternative for distributed generation (DG) if stack life and manufacturing economies of scale can be realized. Currently, stacks last approximately 2 years and few systems are produced each year because of the relatively high cost of electricity from the systems. If mass manufacturing (10,000 units per year) and a stack life of 15 years can be reached, the cost of electricity from an NGSOFC system is estimated to be about 7.7 ¢/kWh, well within the price of commercial and residential retail prices at the national level (9.9-10¢/kWh and 11-12 ¢/kWh, respectively). With an additional 5 ¢/kWh in estimated additional benefits from DG, NGSOFC could be well positioned to replace the forecasted 59-77 gigawatts of capacity loss resulting from coal plant closures due to stricter emissions regulations and low natural gas prices.

  10. Accelerated testing of solid oxide fuel cell stacks for micro combined heat and power application

    NASA Astrophysics Data System (ADS)

    Hagen, Anke; Høgh, Jens Valdemar Thorvald; Barfod, Rasmus

    2015-12-01

    State-of-the-art (SoA) solid oxide fuel cell (SOFC) stacks are tested using profiles relevant for use in micro combined heat and power (CHP) units. Such applications are characterised by dynamic load profiles. In order to shorten the needed testing time and to investigate potential acceleration of degradation, the profiles are executed faster than required for real applications. Operation with fast load cycling, both using hydrogen and methane/steam as fuels, does not accelerate degradation compared to constant operation, which demonstrates the maturity of SoA stacks and enables transferring knowledge from testing at constant conditions to dynamic operation. 7.5 times more cycles than required for 80,000 h lifetime as micro CHP are achieved on one-cell-stack level. The results also suggest that degradation mechanisms that proceed on a longer time-scale, such as creep, might have a more dominating effect for long life-times than regular short time changes of operation. In order to address lifetime testing it is suggested to build a testing program consisting of defined modules that represent different application profiles, such as one module at constant conditions, followed by modules at one set of dynamic conditions etc.

  11. Electricity and disinfectant production from wastewater: Microbial Fuel Cell as a self-powered electrolyser

    NASA Astrophysics Data System (ADS)

    Gajda, Iwona; Greenman, John; Melhuish, Chris; Ieropoulos, Ioannis A.

    2016-05-01

    This study presents a simple and sustainable Microbial Fuel Cell as a standalone, self-powered reactor for in situ wastewater electrolysis, recovering nitrogen from wastewater. A process is proposed whereby the MFC electrical performance drives the electrolysis of wastewater towards the self-generation of catholyte within the same reactor. The MFCs were designed to harvest the generated catholyte in the internal chamber, which showed that liquid production rates are largely proportional to electrical current generation. The catholyte demonstrated bactericidal properties, compared to the control (open-circuit) diffusate, and reduced observable biofilm formation on the cathode electrode. Killing effects were confirmed using bacterial kill curves constructed by exposing a bioluminescent Escherichia coli target, as a surrogate coliform, to catholyte where a rapid kill rate was observed. Therefore, MFCs could serve as a water recovery system, a disinfectant/cleaner generator that limits undesired biofilm formation and as a washing agent in waterless urinals to improve sanitation. This simple and ready to implement MFC system can convert organic waste directly into electricity and self-driven nitrogen along with water recovery. This could lead to the development of energy positive bioprocesses for sustainable wastewater treatment.

  12. State participation in the creation of fuel-cell-based power plants to meet civilian demand in Russia

    SciTech Connect

    Pekhota, F.N.

    1996-04-01

    At present, up to 70% of Russian territory is not covered by central electrical distribution systems. In the field of fuel cell power plants, Russia is at parity with the leading foreign countries with respect to both technical and economic performance and the level of research being conducted. Civilian use of these generating systems on a broad scale, however, demands that a number of problems be solved, particularly those relating to the need for longer plant service life, lower unit cost of electricity, etc. The Ministry of Science and technical Policy of the Russian Federation issued a decree creating a new are of concentration, `Fuel Cell Based Power Plants for Civilian Needs,` in the GNTPR `Environmentally Clean Power Industry,` which will form the basis for financial support in this area out of the federal budget.

  13. The first demonstration of a microbial fuel cell as a viable power supply: Powering a meteorological buoy

    NASA Astrophysics Data System (ADS)

    Tender, Leonard M.; Gray, Sam A.; Groveman, Ethan; Lowy, Daniel A.; Kauffman, Peter; Melhado, Julio; Tyce, Robert C.; Flynn, Darren; Petrecca, Rose; Dobarro, Joe

    2008-05-01

    Here we describe the first demonstration of a microbial fuel cell (MFC) as a practical alternative to batteries for a low-power consuming application. The specific application reported is a meteorological buoy (ca. 18-mW average consumption) that measures air temperature, pressure, relative humidity, and water temperature, and that is configured for real-time line-of-sight RF telemetry of data. The specific type of MFC utilized in this demonstration is the benthic microbial fuel cell (BMFC). The BMFC operates on the bottom of marine environments, where it oxidizes organic matter residing in oxygen depleted sediment with oxygen in overlying water. It is maintenance free, does not deplete (i.e., will run indefinitely), and is sufficiently powerful to operate a wide range of low-power marine-deployed scientific instruments normally powered by batteries. Two prototype BMFCs used to power the buoy are described. The first was deployed in the Potomac River in Washington, DC, USA. It had a mass of 230 kg, a volume of 1.3 m3, and sustained 24 mW (energy equivalent of ca. 16 alkaline D-cells per year at 25 °C). Although not practical due to high cost and extensive in-water manipulation required to deploy, it established the precedence that a fully functional scientific instrument could derive all of its power from a BMFC. It also provided valuable lessons for developing a second, more practical BMFC that was subsequently used to power the buoy in a salt marsh near Tuckerton, NJ, USA. The second version BMFC has a mass of 16 kg, a volume of 0.03 m3, sustains ca. 36 mW (energy equivalent of ca. 26 alkaline D-cells per year at 25 °C), and can be deployed by a single person from a small craft with minimum or no in-water manipulation. This BMFC is being further developed to reduce cost and enable greater power output by electrically connecting multiple units in parallel. Use of this BMFC powering the meteorological buoy highlights the potential impact of BMFCs to enable long

  14. Research and development of a phosphoric acid fuel cell/battery power source integrated in a test-bed bus. Final report

    SciTech Connect

    1996-05-30

    This project, the research and development of a phosphoric acid fuel cell/battery power source integrated into test-bed buses, began as a multi-phase U.S. Department of Energy (DOE) project in 1989. Phase I had a goal of developing two competing half-scale (25 kW) brassboard phosphoric acid fuel cell systems. An air-cooled and a liquid-cooled fuel cell system were developed and tested to verify the concept of using a fuel cell and a battery in a hybrid configuration wherein the fuel cell supplies the average power required for operating the vehicle and a battery supplies the `surge` or excess power required for acceleration and hill-climbing. Work done in Phase I determined that the liquid-cooled system offered higher efficiency.

  15. Research development and demonstration of a fuel cell/battery powered bus system. Interim report, August 1, 1991--April 30, 1992

    SciTech Connect

    Romano, S.; Wimmer, R.

    1992-04-30

    This report describes the progress in the Georgetown University research, development and demonstration project of a fuel cell/battery powered bus system. The topics addressed in the report include vehicle design and application analysis, technology transfer activities, coordination and monitoring of system design and integration contractor, application of fuel cells to other vehicles, current problems, work planned, and manpower, cost and schedule reports.

  16. AN INVESTIGATION TO RESOLVE THE INTERACTION BETWEEN FUEL CELL, POWER CONDITIONING SYSTEM AND APPLICATION LOADS

    SciTech Connect

    Sudip K. Mazumder; Chuck McKintyre; Dan Herbison; Doug Nelson; Comas Haynes; Michael von Spakovsky; Joseph Hartvigsen; S. Elangovan

    2003-11-03

    Solid-Oxide Fuel Cell (SOFC) stacks respond quickly to changes in load and exhibit high part- and full-load efficiencies due to its rapid electrochemistry. However, this is not true for the thermal, mechanical, and chemical balance-of-plant subsystem (BOPS), where load-following time constants are, typically, several orders of magnitude higher. This dichotomy diminishes the reliability and performance of the electrode with increasing demand of load. Because these unwanted phenomena are not well understood, the manufacturers of SOFC use conservative schemes (such as, delayed load-following to compensate for slow BOPS response or expensive inductor filtering) to control stack responses to load variations. This limits the applicability of SOFC systems for load-varying stationary and transportation applications from a cost standpoint. Thus, a need exists for the synthesis of component- and system-level models of SOFC power-conditioning systems and the development of methodologies for investigating the system-interaction issues (which reduce the lifetime and efficiency of a SOFC) and optimizing the responses of each subsystem, leading to optimal designs of power-conditioning electronics and optimal control strategies, which mitigate the electrical-feedback effects. Equally important are ''multiresolution'' finite-element modeling and simulation studies, which can predict the impact of changes in system-level variables (e.g., current ripple and load-transients) on the local current densities, voltages, and temperature (these parameters are very difficult or cumbersome, if not impossible to obtain) within a SOFC cell. Towards that end, for phase I of this project, sponsored by the U.S. DOE (NETL), we investigate the interactions among fuel cell, power-conditioning system, and application loads and their effects on SOFC reliability (durability) and performance. A number of methodologies have been used in Phase I to develop the steady-state and transient nonlinear models of

  17. Design of a high voltage input - output ratio dc-dc converter dedicated to small power fuel cell systems

    NASA Astrophysics Data System (ADS)

    Béthoux, O.; Cathelin, J.

    2010-12-01

    Consuming chemical energy, fuel cells produce simultaneously heat, water and useful electrical power [J.M. Andújar, F. Segura, Renew. Sust. Energy Rev. 13, 2309 (2009)], [J. Larminie, A. Dicks, Fuel Cell Systems Explained, 2nd edn. (John Wiley & Sons, 2003)]. As a matter of fact, the voltage generated by a fuel cell strongly depends on both the load power demand and the operating conditions. Besides, as a result of many design aspects, fuel cells are low voltage and high current electric generators. On the contrary, electric loads are commonly designed for small voltage swing and a high V/I ratio in order to minimize Joule losses. Therefore, electric loads supplied by fuel cells are typically fed by means of an intermediate power voltage regulator. The specifications of such a power converter are to be able to step up the input voltage with a high ratio (a ratio of 10 is a classic situation) and also to work with an excellent efficiency (in order to minimize its size, its weight and its losses) [A. Shahin, B. Huang, J.P. Martin, S. Pierfederici, B. Davat, Energy Conv. Manag. 51, 56 (2010)]. This paper deals with the design of this essential ancillary device. It intends to bring out the best structure for fulfilling this function. Several dc-dc converters with large voltage step-up ratios are introduced. A topology based on a coupled inductor or tapped inductor is closely studied. A detailed modelling is performed with the purpose of providing designing rules. This model is validated with both simulation and implementation. The experimental prototype is based on the following specifications: the fuel cell output voltage ranges from a 50 V open-voltage to a 25 V rated voltage while the load requires a constant 250 V voltage. The studied coupled inductor converter is compared with a classic boost converter commonly used in this voltage elevating application. Even though the voltage regulator faces severe FC specifications, the measured efficiency reaches 96% at the

  18. Project proposals on the creation of Russian-American joint enterprise for investigation, development and manufacture of power plants on the basis of solid oxide fuel cells

    SciTech Connect

    Smotrov, N.V.; Kleschev, Yu.N.

    1996-04-01

    This paper describes a proposal for a joint Russian-American enterprise for performing scientific investigations, development, and manufacture of fuel cell power plants on the basis of the solid oxide fuel cell. RASOFCo. Russian-American Solid Oxide Fuel Cells Company. RASOFCo will provide the series output of the electrochemical generator (ECG) of 1kW power, then of 5kW and 10kW as well as the development and the output of 10kW power plant with the subsequent output of a power plant of greater power. An ECG based on solid oxide fuel cells uses methane as a fuel. Predicted technical characteristics, market analysis, assessment of potential demands for power plants of low power for Tyumentransgas, participants of the joint enterprise and their founding contributions, strategy for manufacture and financing, and management of RASOFCo are discussed.

  19. Fuel Cell Handbook, Fourth Edition

    SciTech Connect

    Stauffer, D.B; Hirschenhofer, J.H.; Klett, M.G.; Engleman, R.R.

    1998-11-01

    Robust progress has been made in fuel cell technology since the previous edition of the Fuel Cell Handbook was published in January 1994. This Handbook provides a foundation in fuel cells for persons wanting a better understanding of the technology, its benefits, and the systems issues that influence its application. Trends in technology are discussed, including next-generation concepts that promise ultra high efficiency and low cost, while providing exceptionally clean power plant systems. Section 1 summarizes fuel cell progress since the last edition and includes existing power plant nameplate data. Section 2 addresses the thermodynamics of fuel cells to provide an understanding of fuel cell operation at two levels (basic and advanced). Sections 3 through 6 describe the four major fuel cell types and their performance based on cell operating conditions. The section on polymer electrolyte membrane fuel cells has been added to reflect their emergence as a significant fuel cell technology. Phosphoric acid, molten carbonate, and solid oxide fuel cell technology description sections have been updated from the previous edition. New information indicates that manufacturers have stayed with proven cell designs, focusing instead on advancing the system surrounding the fuel cell to lower life cycle costs. Section 7, Fuel Cell Systems, has been significantly revised to characterize near-term and next-generation fuel cell power plant systems at a conceptual level of detail. Section 8 provides examples of practical fuel cell system calculations. A list of fuel cell URLs is included in the Appendix. A new index assists the reader in locating specific information quickly.

  20. Operating experience with a 250 kW el molten carbonate fuel cell (MCFC) power plant

    NASA Astrophysics Data System (ADS)

    Bischoff, Manfred; Huppmann, Gerhard

    The MTU MCFC program is carried out by a European consortium comprising the German companies MTU Friedrichshafen GmbH, Ruhrgas AG and RWE Energie AG as well as the Danish company Energi E2 S/A. MTU acts as consortium leader. The company shares a license and technology exchange agreement with Fuel Cell Energy Inc., Danbury, CT, USA (formerly Energy Research Corp., ERC). The program was started in 1990 and covers a period of about 10 years. The highlights of this program to date are: Considerable improvements regarding component stability have been demonstrated on laboratory scale. Manufacturing technology has been developed to a point which enables the consortium to fabricate the porous components on a 250 cm 2 scale. Several large area stacks with 5000-7660 cm 2 cell area and a power range of 3-10 kW have been tested at the facilities in Munich (Germany) and Kyndby (Denmark). These stacks have been supplied by FCE. As far as the system design is concerned it was soon realized that conventional systems do not hold the promise for competitive power plants. A system analysis led to the conclusion that a new innovative design approach is required. As a result the "Hot Module" system was developed by the consortium. A Hot Module combines all the components of a MCFC system operating at the similar temperatures and pressures into a common thermally insulated vessel. In August 1997 the consortium started its first full size Hot Module MCFC test plant at the facilities of Ruhrgas AG in Dorsten, Germany. The stack was assembled in Munich using 292 cell packages purchased from FCE. The plant is based on the consortium's unique and proprietary "Hot Module" concept. It operates on pipeline natural gas and was grid connected on 16 August 1997. After a total of 1500 h of operation, the plant was intentionally shut down in a controlled manner in April 1998 for post-test analysis. The Hot Module system concept has demonstrated its functionality. The safety concept has been

  1. LOW-TEMPERATURE, ANODE-SUPPORTED HIGH POWER DENSITY SOLID OXIDE FUEL CELLS WITH NANOSTRUCTURED ELECTRODES

    SciTech Connect

    Anil V. Virkar

    2001-06-21

    A simple, approximate analysis of the effect of differing cathode and anode areas on the measurement of cell performance on anode-supported solid oxide fuel cells, wherein the cathode area is smaller than the anode area, is presented. It is shown that the effect of cathode area on cathode polarization, on electrolyte contribution, and on anode resistance, as normalized on the basis of the cathode area, is negligible. There is a small but measurable effect on anode polarization, which results from concentration polarization. Effectively, it is the result of a greater amount of fuel transported to the anode/electrolyte interface in cases wherein the anode area is larger than the cathode area. Experiments were performed on cells made with differing cathode areas and geometries. Cathodic and anodic overpotentials measured using reference electrodes, and the measured ohmic area specific resistances by current interruption, were in good agreement with expectations based on the analysis presented. At 800 C, the maximum power density measured with a cathode area of {approx}1.1 cm{sup 2} was {approx}1.65 W/cm{sup 2} compared to {approx}1.45 W/cm{sup 2} for cathode area of {approx}2 cm{sup 2}, for anode thickness of {approx}1.3 mm, with hydrogen as the fuel and air as the oxidant. At 750 C, the measured maximum power densities were {approx}1.3 W/cm{sup 2} for the cell with cathode area {approx}1.1 cm{sup 2}, and {approx}1.25 W/cm{sup 2} for the cell with cathode area {approx}2 cm{sup 2}.

  2. Fuel Cell Handbook, Fifth Edition

    SciTech Connect

    Energy and Environmental Solutions

    2000-10-31

    Progress continues in fuel cell technology since the previous edition of the Fuel Cell Handbook was published in November 1998. Uppermost, polymer electrolyte fuel cells, molten carbonate fuel cells, and solid oxide fuel cells have been demonstrated at commercial size in power plants. The previously demonstrated phosphoric acid fuel cells have entered the marketplace with more than 220 power plants delivered. Highlighting this commercial entry, the phosphoric acid power plant fleet has demonstrated 95+% availability and several units have passed 40,000 hours of operation. One unit has operated over 49,000 hours. Early expectations of very low emissions and relatively high efficiencies have been met in power plants with each type of fuel cell. Fuel flexibility has been demonstrated using natural gas, propane, landfill gas, anaerobic digester gas, military logistic fuels, and coal gas, greatly expanding market opportunities. Transportation markets worldwide have shown remarkable interest in fuel cells; nearly every major vehicle manufacturer in the U.S., Europe, and the Far East is supporting development. This Handbook provides a foundation in fuel cells for persons wanting a better understanding of the technology, its benefits, and the systems issues that influence its application. Trends in technology are discussed, including next-generation concepts that promise ultrahigh efficiency and low cost, while providing exceptionally clean power plant systems. Section 1 summarizes fuel cell progress since the last edition and includes existing power plant nameplate data. Section 2 addresses the thermodynamics of fuel cells to provide an understanding of fuel cell operation at two levels (basic and advanced). Sections 3 through 8 describe the six major fuel cell types and their performance based on cell operating conditions. Alkaline and intermediate solid state fuel cells were added to this edition of the Handbook. New information indicates that manufacturers have stayed

  3. High energy efficiency and high power density proton exchange membrane fuel cells: Electrode kinetics and mass transport

    NASA Technical Reports Server (NTRS)

    Srinivasan, Supramaniam; Velev, Omourtag A.; Parthasathy, Arvind; Manko, David J.; Appleby, A. John

    1991-01-01

    The development of proton exchange membrane (PEM) fuel cell power plants with high energy efficiencies and high power densities is gaining momentum because of the vital need of such high levels of performance for extraterrestrial (space, underwater) and terrestrial (power source for electric vehicles) applications. Since 1987, considerable progress has been made in achieving energy efficiencies of about 60 percent at a current density of 200 mA/sq cm and high power densities (greater than 1 W/sq cm) in PEM fuel cells with high (4 mg/sq cm) or low (0.4 mg/sq cm) platinum loadings in electrodes. The following areas are discussed: (1) methods to obtain these high levels of performance with low Pt loading electrodes - by proton conductor impregnation into electrodes, localization of Pt near front surface; (2) a novel microelectrode technique which yields electrode kinetic parameters for oxygen reduction and mass transport parameters; (3) demonstration of lack of water transport from anode to cathode; (4) modeling analysis of PEM fuel cell for comparison with experimental results and predicting further improvements in performance; and (5) recommendations of needed research and development for achieving the above goals.

  4. A Total Cost of Ownership Model for Low Temperature PEM Fuel Cells in Combined Heat and Power and Backup Power Applications

    SciTech Connect

    University of California, Berkeley; Wei, Max; Lipman, Timothy; Mayyas, Ahmad; Chien, Joshua; Chan, Shuk Han; Gosselin, David; Breunig, Hanna; Stadler, Michael; McKone, Thomas; Beattie, Paul; Chong, Patricia; Colella, Whitney; James, Brian

    2014-06-23

    A total cost of ownership model is described for low temperature proton exchange membrane stationary fuel cell systems for combined heat and power (CHP) applications from 1-250kW and backup power applications from 1-50kW. System designs and functional specifications for these two applications were developed across the range of system power levels. Bottom-up cost estimates were made for balance of plant costs, and detailed direct cost estimates for key fuel cell stack components were derived using design-for-manufacturing-and-assembly techniques. The development of high throughput, automated processes achieving high yield are projected to reduce the cost for fuel cell stacks to the $300/kW level at an annual production volume of 100 MW. Several promising combinations of building types and geographical location in the U.S. were identified for installation of fuel cell CHP systems based on the LBNL modelling tool DER CAM. Life-cycle modelling and externality assessment were done for hotels and hospitals. Reduced electricity demand charges, heating credits and carbon credits can reduce the effective cost of electricity ($/kWhe) by 26-44percent in locations such as Minneapolis, where high carbon intensity electricity from the grid is displaces by a fuel cell system operating on reformate fuel. This project extends the scope of existing cost studies to include externalities and ancillary financial benefits and thus provides a more comprehensive picture of fuel cell system benefits, consistent with a policy and incentive environment that increasingly values these ancillary benefits. The project provides a critical, new modelling capacity and should aid a broad range of policy makers in assessing the integrated costs and benefits of fuel cell systems versus other distributed generation technologies.

  5. Optimizing membrane electrode assembly of direct methanol fuel cells for portable power

    NASA Astrophysics Data System (ADS)

    Liu, Fuqiang

    Direct methanol fuel cells (DMFCs) for portable power applications require high power density, high-energy conversion efficiency and compactness. These requirements translate to fundamental properties of high methanol oxidation and oxygen reduction kinetics, as well as low methanol and water crossover. In this thesis a novel membrane electrode assembly (MEA) for direct methanol fuel cells has been developed, aiming to improve these fundamental properties. Firstly, methanol oxidation kinetics has been enhanced and methanol crossover has been minimized by proper control of ionomer crystallinity and its swelling in the anode catalyst layer through heat-treatment. Heat-treatment has a major impact on anode characteristics. The short-cured anode has low ionomer crystallinity, and thus swells easily when in contact with methanol solution to create a much denser anode structure, giving rise to higher methanol transport resistance than the long-cured anode. Variations in interfacial properties in the anode catalyst layer (CL) during cell conditioning were also characterized, and enhanced kinetics of methanol oxidation and severe limiting current phenomenon were found to be caused by a combination of interfacial property variations and swelling of ionomer over time. Secondly, much effort has been expended to develop a cathode CL suitable for operation under low air stoichiometry. The effects of fabrication procedure, ionomer content, and porosity distribution on the microstructure and cathode performance under low air stoichiometry are investigated using electrochemical and surface morphology characterizations to reveal the correlation between microstructure and electrochemical behavior. At the same time, computational fluid dynamics (CFD) models of DMFC cathodes have been developed to theoretically interpret the experimental results, to investigate two-phase transport, and to elucidate mechanism of cathode mixed potential due to methanol crossover. Thirdly, a MEA with low

  6. Landfill gas cleanup for carbonate fuel cell power generation. Final report

    SciTech Connect

    Steinfield, G.; Sanderson, R.

    1998-02-01

    Landfill gas represents a significant fuel resource both in the US and worldwide. The emissions of landfill gas from existing landfills has become an environmental liability contributing to global warming and causing odor problems. Landfill gas has been used to fuel reciprocating engines and gas turbines, and may also be used to fuel carbonate fuel cells. Carbonate fuel cells have high conversion efficiencies and use the carbon dioxide present in landfill gas as an oxidant. There are, however, a number of trace contaminants in landfill gas that contain chlorine and sulfur which are deleterious to fuel cell operation. Long-term economical operation of fuel cells fueled with landfill gas will, therefore, require cleanup of the gas to remove these contaminants. The overall objective of the work reported here was to evaluate the extent to which conventional contaminant removal processes could be combined to economically reduce contaminant levels to the specifications for carbonate fuel cells. A pilot plant cleaned approximately 970,000 scf of gas over 1,000 hours of operation. The testing showed that the process could achieve the following polished gas concentrations: less than 80 ppbv hydrogen sulfide; less than 1 ppmv (the detection limit) organic sulfur; less than 300 ppbv hydrogen chloride; less than 20--80 ppbv of any individual chlorinated hydrocarbon; and 1.5 ppm sulfur dioxide.

  7. Adaptation of a commercially available 200 kW natural gas fuel cell power plant for operation on a hydrogen rich gas stream

    SciTech Connect

    Maston, V.A.

    1997-12-01

    International Fuel Cells (IFC) has designed a hydrogen fueled fuel cell power plant based on a modification of its standard natural gas fueled PC25{trademark} C fuel cell power plant. The natural gas fueled PC25 C is a 200 kW, fuel cell power plant that is commercially available. The program to accomplish the fuel change involved deleting the natural gas processing elements, designing a new fuel pretreatment subsystem, modifying the water and thermal management subsystem, developing a hydrogen burner to combust unconsumed hydrogen, and modifying the control system. Additionally, the required modifications to the manufacturing and assembly procedures necessary to allow the hydrogen fueled power plant to be manufactured in conjunction with the on-going production of the standard PC25 C power plants were identified. This work establishes the design and manufacturing plan for the 200 kW hydrogen fueled PC25 power plant.

  8. Purge gas protected transportable pressurized fuel cell modules and their operation in a power plant

    DOEpatents

    Zafred, P.R.; Dederer, J.T.; Gillett, J.E.; Basel, R.A.; Antenucci, A.B.

    1996-11-12

    A fuel cell generator apparatus and method of its operation involves: passing pressurized oxidant gas and pressurized fuel gas into modules containing fuel cells, where the modules are each enclosed by a module housing surrounded by an axially elongated pressure vessel, and where there is a purge gas volume between the module housing and pressure vessel; passing pressurized purge gas through the purge gas volume to dilute any unreacted fuel gas from the modules; and passing exhaust gas and circulated purge gas and any unreacted fuel gas out of the pressure vessel; where the fuel cell generator apparatus is transportable when the pressure vessel is horizontally disposed, providing a low center of gravity. 11 figs.

  9. Fuel cells 101

    SciTech Connect

    Hirschenhofer, J.H.

    1999-07-01

    This paper discusses the various types of fuel cells, the importance of cell voltage, fuel processing for natural gas, cell stacking, fuel cell plant description, advantages and disadvantages of the types of fuel cells, and applications. The types covered include: polymer electrolyte fuel cell, alkaline fuel cell, phosphoric acid fuel cell; molten carbonate fuel cell, and solid oxide fuel cell.

  10. Modelling for part-load operation of solid oxide fuel cell-gas turbine hybrid power plant

    NASA Astrophysics Data System (ADS)

    Chan, S. H.; Ho, H. K.; Tian, Y.

    This paper presents the work on part-load operation of a power generation system composed of a solid oxide fuel cell and a gas turbine (SOFC-GT) which operate on natural gas. The system consists of an internal reforming SOFC (IRSOFC) stack, an external combustor, two turbines, two compressors, two recuperators and one heat-recovery steam generator (HRSG). Based on experience in different levels of modelling of the fuel cell, fuel cell stack and integrated system and the inherent characteristics of a IRSOFC-GT hybrid power plant, a practical approach for simplifying part-load operation of the system is proposed. Simulation results show that an IRSOFC-GT hybrid system could achieve a net electrical efficiency and system efficiency (including waste heat recovery for steam generation) of greater than 60 and 80%, respectively, under full-load operation. Due to the complexity of the interaction of the components and safety requirements, the part-load performance of a IRSOFC-GT hybrid power plant is poorer than that under full-load operation.

  11. Zero Emission Power Plants Using Solid Oxide Fuel Cells and Oxygen Transport Membranes

    SciTech Connect

    Shockling, Larry A.; Huang, Keqin; Gilboy, Thomas E.; Christie, G. Maxwell; Raybold, Troy M.

    2001-11-06

    Siemens Westinghouse Power Corp. (SWPC) is engaged in the development of Solid Oxide Fuel Cell stationary power systems. SWPC has combined DOE Developmental funds with commercial customer funding to establish a record of successful SOFC field demonstration power systems of increasing size. SWPC will soon deploy the first unit of a newly developed 250 kWe Combined Heat Power System. It will generate electrical power at greater than 45% electrical efficiency. The SWPC SOFC power systems are equipped to operate on lower number hydrocarbon fuels such as pipeline natural gas, which is desulfurized within the SOFC power system. Because the system operates with a relatively high electrical efficiency, the CO2 emissions, {approx}1.0 lb CO2/ kW-hr, are low. Within the SOFC module the desulfurized fuel is utilized electrochemically and oxidized below the temperature for NOx generation. Therefore the NOx and SOx emissions for the SOFC power generation system are near negligible. The byproducts of the power generation from hydrocarbon fuels that are released into the environment are CO2 and water vapor. This forward looking DOE sponsored Vision 21 program is supporting the development of methods to capture and sequester the CO2, resulting in a Zero Emission power generation system. To accomplish this, SWPC is developing a SOFC module design, to be demonstrated in operating hardware, that will maintain separation of the fuel cell anode gas, consisting of H2, CO, H2O and CO2, from the vitiated air. That anode gas, the depleted fuel stream, containing less than 18% (H2 + CO), will be directed to an Oxygen Transport Membrane (OTM) Afterburner that is being developed by Praxair, Inc.. The OTM is supplied air and the depleted fuel. The OTM will selectively transport oxygen across the membrane to oxidize the remaining H2 and CO. The water vapor is then condensed from the totally 1.5.DOC oxidized fuel stream exiting the afterburner, leaving only the CO2 in gaseous form. That CO2 can

  12. World wide IFC phosphoric acid fuel cell implementation

    SciTech Connect

    King, J.M. Jr

    1996-04-01

    International Fuel Cells, a subsidary of United technologies Corporation, is engaged in research and development of all types of fuel cell technologies and currently manufactures alkaline fuel cell power plants for the U.S. manned space flight program and natural gas fueled stationary power plants using phosphoric acid fuel cells. This paper describes the phosphoric acid fuel cell power plants.

  13. Composite Cathode for High-Power Density Solid Oxide Fuel Cells

    SciTech Connect

    Ilwon Kim; Scott Barnett; Yi Jiang; Manoj Pillai; Nikkia McDonald; Dan Gostovic; Zhongryang Zhan; Jiang Liu

    2004-01-31

    Reduction of solid oxide fuel cell (SOFC) operating temperature will play a key role in reducing the stack cost by allowing the use of low-cost metallic interconnects and new approaches to sealing, while making applications such as transportation more feasible. Reported results for anode-supported SOFCs show that cathode polarization resistance is the primary barrier to achieving high power densities at operating temperatures of 700 C and lower. This project aims to identify and develop composite cathodes that could reduce SOFC operating temperatures below 700 C. This effort focuses on study and use of (La,Sr)(Co,Fe)O{sub 3} (LSCF) based composite cathodes, which have arguably the best potential to substantially improve on the currently-used, (La,Sr)MnO{sub 3}-Yttria-stabilized Zirconia. During this Phase I, it was successfully demonstrated that high performances can be achieved with LSCF/Gadolinium-Doped Ceria composite cathodes on Ni-based anode supported cells operating at 700 C or lower. We studied electrochemical reactions at LSCF/Yttria-stabilized Zirconia (YSZ) interfaces, and observed chemical reactions between LSCF and YSZ. By using ceria electrolytes or YSZ electrolytes with ceria diffusion barrier layers, the chemical reactions between LSCF and electrolytes were prevented under cathode firing conditions necessary for the optimal adhesion of the cathodes. The protection provided by ceria layer is expected to be adequate for stable long-term cathode performances, but more testing is needed to verify this. Using ceria-based barrier layers, high performance Ni-YSZ anode supported cells have been demonstrated with maximum power densities of 0.8W/cm2 at 700 C and 1.6W/cm{sup 2} at 800 C. Ni-SDC anode supported cells with SDC electrolytes yielded >1W/cm{sup 2} at 600 C. We speculate that the power output of Ni-YSZ anode supported cell at 700 C and lower, was limited by the quality of the Ceria and Ceria YSZ interface. Improvements in the low

  14. Miniature ceramic fuel cell

    DOEpatents

    Lessing, Paul A.; Zuppero, Anthony C.

    1997-06-24

    A miniature power source assembly capable of providing portable electricity is provided. A preferred embodiment of the power source assembly employing a fuel tank, fuel pump and control, air pump, heat management system, power chamber, power conditioning and power storage. The power chamber utilizes a ceramic fuel cell to produce the electricity. Incoming hydro carbon fuel is automatically reformed within the power chamber. Electrochemical combustion of hydrogen then produces electricity.

  15. Fuel cells, batteries and super-capacitors stand-alone power systems management using optimal/flatness based-control

    NASA Astrophysics Data System (ADS)

    Benaouadj, M.; Aboubou, A.; Ayad, M. Y.; Bahri, M.; Boucetta, A.

    2016-07-01

    In this work, an optimal control (under constraints) based on the Pontryagin's maximum principle is used to optimally manage energy flows in a basic PEM (Proton Exchange Membrane) fuel cells system associated to lithium-ion batteries and supercapacitors through a common DC bus having a voltage to stabilize using the differential flatness approach. The adaptation of voltage levels between different sources and load is ensured by use of three DC-DC converters, one boost connected to the PEM fuel cells, while the two others are buck/boost and connected to the lithiumion batteries and supercapacitors. The aim of this paper is to develop an energy management strategy that is able to satisfy the following objectives: - Impose the power requested by a habitat (representing the load) according to a proposed daily consumption profile, - Keep fuel cells working at optimal power delivery conditions, - Maintain constant voltage across the common DC bus, - Stabilize the batteries voltage and stored quantity of charge at desired values given by the optimal control.Results obtained under MATLAB/Simulink environment prove that the cited objectives are satisfied, validating then, effectiveness and complementarity between the optimal and flatness concepts proposed for energy management. Note that this study is currently in experimentally validation within MSE Laboratory.

  16. Method to improve reliability of a fuel cell system using low performance cell detection at low power operation

    DOEpatents

    Choi, Tayoung; Ganapathy, Sriram; Jung, Jaehak; Savage, David R.; Lakshmanan, Balasubramanian; Vecasey, Pamela M.

    2013-04-16

    A system and method for detecting a low performing cell in a fuel cell stack using measured cell voltages. The method includes determining that the fuel cell stack is running, the stack coolant temperature is above a certain temperature and the stack current density is within a relatively low power range. The method further includes calculating the average cell voltage, and determining whether the difference between the average cell voltage and the minimum cell voltage is greater than a predetermined threshold. If the difference between the average cell voltage and the minimum cell voltage is greater than the predetermined threshold and the minimum cell voltage is less than another predetermined threshold, then the method increments a low performing cell timer. A ratio of the low performing cell timer and a system run timer is calculated to identify a low performing cell.

  17. Self-cooling mono-container fuel cell generators and power plants using an array of such generators

    DOEpatents

    Gillett, J.E.; Dederer, J.T.; Zafred, P.R.

    1998-05-12

    A mono-container fuel cell generator contains a layer of interior insulation, a layer of exterior insulation and a single housing between the insulation layers, where fuel cells, containing electrodes and electrolyte, are surrounded by the interior insulation in the interior of the generator, and the generator is capable of operating at temperatures over about 650 C, where the combination of interior and exterior insulation layers have the ability to control the temperature in the housing below the degradation temperature of the housing material. The housing can also contain integral cooling ducts, and a plurality of these generators can be positioned next to each other to provide a power block array with interior cooling. 7 figs.

  18. Self-cooling mono-container fuel cell generators and power plants using an array of such generators

    DOEpatents

    Gillett, James E.; Dederer, Jeffrey T.; Zafred, Paolo R.

    1998-01-01

    A mono-container fuel cell generator (10) contains a layer of interior insulation (14), a layer of exterior insulation (16) and a single housing (20) between the insulation layers, where fuel cells, containing electrodes and electrolyte, are surrounded by the interior insulation (14) in the interior (12) of the generator, and the generator is capable of operating at temperatures over about 650.degree. C., where the combination of interior and exterior insulation layers have the ability to control the temperature in the housing (20) below the degradation temperature of the housing material. The housing can also contain integral cooling ducts, and a plurality of these generators can be positioned next to each other to provide a power block array with interior cooling.

  19. Fuel cell sesquicentennial

    NASA Technical Reports Server (NTRS)

    Cohn, E. M.

    1979-01-01

    The development of fuel cell technology is summarized, and the potential for utility-type fuel cell installations is assessed on the occasion of the 150th anniversary of the construction of the first fuel cell by Sir William Grove. The only functional fuel-cell systems developed to date, the hydrogen-oxygen cells used by NASA, are indicated, and hydrazine and alcohol (methanol) cells are considered. Areas requiring development before the implementation of fuel cells as general purpose utility-type electric generators include catalysts for naturally occurring hydrocarbons or processes for low-cost methanol or hydrazine production, efficient means of scrubbing and enriching air, self-regulating systems, and 15- to 20-fold power density increases. It is argued that although ideas for eliminating certain of the above-mentioned problems have been proposed, fuel-cell systems can never be expected to equal the efficiency, reliability and low cost of conventional power plants, and thus developmental support should be discontinued.

  20. Case Study: Fuel Cells Provide Combined Heat and Power at Verizon's Garden City Central Office

    SciTech Connect

    2010-12-01

    This case study describes how Verizon's Central Office in Garden City, NY, installed a 1.4-MW phosphoric acid fuel cell system as an alternative solution to bolster electric reliability, optimize the company's energy use, and reduce costs in an environmentally responsible manner.

  1. SYSTEM AND PROCESS FOR PRODUCTION OF METHANOL FROM COMBINED WIND TURBINE AND FUEL CELL POWER

    EPA Science Inventory

    The paper examines an integrated use of ultra-clean wind turbines and high temperature fuel cells to produce methanol, especially for transportation purposes. The principal utility and application of the process is the production of transportation fuel from domestic resources to ...

  2. Thermo-economic modeling of an indirectly coupled solid oxide fuel cell/gas turbine hybrid power plant

    NASA Astrophysics Data System (ADS)

    Cheddie, Denver F.; Murray, Renique

    Power generation using gas turbine (GT) power plants operating on the Brayton cycle suffers from low efficiencies, resulting in poor fuel to power conversion. A solid oxide fuel cell (SOFC) is proposed for integration into a 10 MW gas turbine power plant, operating at 30% efficiency, in order to improve system efficiencies and economics. The SOFC system is indirectly coupled to the gas turbine power plant, paying careful attention to minimize the disruption to the GT operation. A thermo-economic model is developed for the hybrid power plant, and predicts an optimized power output of 20.6 MW at 49.9% efficiency. The model also predicts a break-even per-unit energy cost of USD 4.65 ¢ kWh -1 for the hybrid system based on futuristic mass generation SOFC costs. This shows that SOFCs may be indirectly integrated into existing GT power systems to improve their thermodynamic and economic performance.

  3. Handbook of fuel cell performance

    SciTech Connect

    Benjamin, T.G.; Camara, E.H.; Marianowski, L.G.

    1980-05-01

    The intent of this document is to provide a description of fuel cells, their performances and operating conditions, and the relationship between fuel processors and fuel cells. This information will enable fuel cell engineers to know which fuel processing schemes are most compatible with which fuel cells and to predict the performance of a fuel cell integrated with any fuel processor. The data and estimates presented are for the phosphoric acid and molten carbonate fuel cells because they are closer to commercialization than other types of fuel cells. Performance of the cells is shown as a function of operating temperature, pressure, fuel conversion (utilization), and oxidant utilization. The effect of oxidant composition (for example, air versus O/sub 2/) as well as fuel composition is examined because fuels provided by some of the more advanced fuel processing schemes such as coal conversion will contain varying amounts of H/sub 2/, CO, CO/sub 2/, CH/sub 4/, H/sub 2/O, and sulfur and nitrogen compounds. A brief description of fuel cells and their application to industrial, commercial, and residential power generation is given. The electrochemical aspects of fuel cells are reviewed. The phosphoric acid fuel cell is discussed, including how it is affected by operating conditions; and the molten carbonate fuel cell is discussed. The equations developed will help systems engineers to evaluate the application of the phosphoric acid and molten carbonate fuel cells to commercial, utility, and industrial power generation and waste heat utilization. A detailed discussion of fuel cell efficiency, and examples of fuel cell systems are given.

  4. Hybrid Fuel Cell Technology Overview

    SciTech Connect

    None available

    2001-05-31

    For the purpose of this STI product and unless otherwise stated, hybrid fuel cell systems are power generation systems in which a high temperature fuel cell is combined with another power generating technology. The resulting system exhibits a synergism in which the combination performs with an efficiency far greater than can be provided by either system alone. Hybrid fuel cell designs under development include fuel cell with gas turbine, fuel cell with reciprocating (piston) engine, and designs that combine different fuel cell technologies. Hybrid systems have been extensively analyzed and studied over the past five years by the Department of Energy (DOE), industry, and others. These efforts have revealed that this combination is capable of providing remarkably high efficiencies. This attribute, combined with an inherent low level of pollutant emission, suggests that hybrid systems are likely to serve as the next generation of advanced power generation systems.

  5. 1990 fuel cell seminar: Program and abstracts

    SciTech Connect

    Not Available

    1990-12-31

    This volume contains author prepared short resumes of the presentations at the 1990 Fuel Cell Seminar held November 25-28, 1990 in Phoenix, Arizona. Contained herein are 134 short descriptions organized into topic areas entitled An Environmental Overview, Transportation Applications, Technology Advancements for Molten Carbonate Fuel Cells, Technology Advancements for Solid Fuel Cells, Component Technologies and Systems Analysis, Stationary Power Applications, Marine and Space Applications, Technology Advancements for Acid Type Fuel Cells, and Technology Advancement for Solid Oxide Fuel Cells.

  6. Hybrid Solid Oxide Fuel Cell and Thermoelectric Generator for Maximum Power Output in Micro-CHP Systems

    NASA Astrophysics Data System (ADS)

    Rosendahl, L. A.; Mortensen, Paw V.; Enkeshafi, Ali A.

    2011-05-01

    One of the most obvious early market applications for thermoelectric generators (TEG) is decentralized micro combined heat and power (CHP) installations of 0.5 kWe to 5 kWe based on fuel cell technology. Through the use of TEG technology for waste heat recovery it is possible to increase the electricity production in micro-CHP systems by more than 15%, corresponding to system electrical efficiency increases of some 4 to 5 percentage points. This will make fuel cell-based micro-CHP systems very competitive and profitable and will also open opportunities in a number of other potential business and market segments which are not yet quantified. This paper quantifies a micro-CHP system based on a solid oxide fuel cell (SOFC) and a high-performance TE generator. Based on a 3 kW fuel input, the hybrid SOFC implementation boosts electrical output from 945 W to 1085 W, with 1794 W available for heating purposes.

  7. Conceptual designs of advanced high-temperature desulfurization processes: Volume 1, Molten carbonate fuel cell power plants: Final report

    SciTech Connect

    Klett, M.G.; Boulay, R.B.; Buchanan, T.L.; Chen, H.T.; Fischer, W.H.; Hirschenhofer, J.H.; Losovsky, M.L.; Underkoffler, V.S.

    1986-12-01

    Purpose of this effort is to provide conceptual commercial-scale designs, including engineering, relative cost, and economic information for high-temperature desulfurization processes. The commercial-scale processes were designed as an integral part of a nominal 100-MW(e) power plant. Two types of power plants were considered, a coal gasification molten carbonate fuel cell (MCFC) power plant and an integrated gasification combined-cycle (IGCC) power plant. Three desulfurization processes combined with three different gasification processes were evaluated, for a total of 16 cases for the MCFC power plant. The three desulfurization processes evaluated were: METC's zinc ferrite process, Battelle Pacific Northwest Laboratory's solid-supported molten salt process, and Institute of Gas Technology's mixed metal oxide process. Volume I of this report presents the results for the MCFC power plant.

  8. Technology development goals for automotive fuel cell power systems. Final report, Appendix B-2

    SciTech Connect

    Thomas, C.E.; James, B.D.

    1995-07-01

    Directed Technologies, Inc. has previously submitted a detailed technical assessment and concept design for a mid-size, five-passenger fuel cell electric vehicle (FCEV), under contract to the Argonne National Laboratory. As a supplement to that contract, DTI has reviewed the literature and conducted a preliminary evaluation of two energy carriers for the FCEV: hydrogen and methanol. This report compares the estimated fuel efficiency, cost of producing and delivering the fuel, and the resultant life cycle costs of the FCEV when fueled directly by hydrogen and when fueled by methanol with on-board reforming to produce the required hydrogen-rich gas for the fuel cell. This work will be supplemented and expanded under the Ford contract with the Department of Energy to develop the FCEV and its fuel infrastructure.

  9. Bus industry market study. Report -- Task 3.2: Fuel cell/battery powered bus system

    SciTech Connect

    Zalbowitz, M.

    1992-06-02

    In support of the commercialization of fuel cells for transportation, Georgetown University, as a part of the DOE/DOT Fuel Cell Transit Bus Program, conducted a market study to determine the inventory of passenger buses in service as of December, 1991, the number of buses delivered in 1991 and an estimate of the number of buses to be delivered in 1992. Short term and long term market projections of deliveries were also made. Data was collected according to type of bus and the field was divided into the following categories which are defined in the report: transit buses, school buses, commercial non-transit buses, and intercity buses. The findings of this study presented with various tables of data collected from identified sources as well as narrative analysis based upon interviews conducted during the survey.

  10. A novel control and physical realization of a clean hybrid hydrogen fuel-cell/battery low-power personal electric vehicle

    NASA Astrophysics Data System (ADS)

    Watkins, Andrew N.

    With the rapid continuation of global warming, high concentrations of pollutants, and foreign oil conflicts, the green energy push has now begun to manifest into great advancements in renewable or clean energies. Fuel-cells have a promising future for mobile power such as the automotive industry, distributed generation, and portable auxiliary power supplies. The type of fuel-cell that has the most focus today is the hydrogen Proton Exchange Membrane (PEM) fuel-cell. It is widely accepted that a fuel-cell cannot effectively supply a dynamic load on its own. In order to correct this drawback and make the fuel-cell system useful for all occasions, a hybrid FC/storage device system needs to be implemented. In this type of system, a balance is created between the high-energy fuel-cell and the high-power storage devices. In this thesis, a hybrid fuel-cell system topology favorable for use in a "personal" electric vehicle such as a scooter is proposed. This topology consists of a fuel-cell connected directly to the batteries and load via a DC link converter. The converter is used to manage the flow of power within the system. In order to have this flow of power to be stable and within operational limits of the devices, a novel adaptive control algorithm implementing six transfer functions based on six major operating conditions is developed. The development of the adaptive algorithm and the implementation of hardware tests were carried out by Matlab/Simulink and dSPACE. The results of the tests showed that the control algorithm was successful at regulating power flow as well as facilitating DC link stability and accuracy at the major operating points.

  11. Develop and test fuel cell powered on-site integrated total energy system

    NASA Technical Reports Server (NTRS)

    Kaufman, A.; Feigenbaum, H.; Wang, C. L.; Werth, J.; Whelan, J. A.

    1983-01-01

    Test results are presented for a 24 cell, two sq ft (4kW) stack. This stack is a precursor to a 25kW stack that is a key milestone. Results are discussed in terms of cell performance, electrolyte management, thermal management, and reactant gas manifolding. The results obtained in preliminary testing of a 50kW methanol processing subsystem are discussed. Subcontracting activities involving application analysis for fuel cell on site integrated energy systems are updated.

  12. Anode modification with formic acid: A simple and effective method to improve the power generation of microbial fuel cells

    NASA Astrophysics Data System (ADS)

    Liu, Weifeng; Cheng, Shaoan; Guo, Jian

    2014-11-01

    The physicochemical properties of anode material directly affect the anodic biofilm formation and electron transfer, thus are critical for the power generation of microbial fuel cells (MFCs). In this work, carbon cloth anode was modified with formic acid to enhance the power production of MFCs. Formic acid modification of anode increased the maximum power density of a single-chamber air-cathode MFC by 38.1% (from 611.5 ± 6 mW/m2 to 877.9 ± 5 mW/m2). The modification generated a cleaner electrode surface and a reduced content of oxygen and nitrogen groups on the anode. The surface changes facilitated bacterial growth on the anode and resulted in an optimized microbial community. Thus, the electron transfer rate on the modified anodes was enhanced remarkably, contributing to a higher power output of MFCs. Anode modification with formic acid could be an effective and simple method for improving the power generation of MFCs. The modification method holds a huge potential for large scale applications and is valuable for the scale-up and commercialization of microbial fuel cells.

  13. Fuel cell/gas turbine integration

    SciTech Connect

    Knickerbocker, T.

    1995-10-19

    The Allison Engine Company`s very high efficiency fuel cell/advanced turbine power cycle program is discussed. The power cycle has the following advantages: high system efficiency potential, reduced emissions inherent to fuel cells, unmanned operation(no boiler) particularly suited for distributed power, and existing product line matches fuel cell operating environment. Cost effectiveness, estimates, and projections are given.

  14. Off-Design Performance Analysis of a Solid-Oxide Fuel Cell/Gas Turbine Hybrid for Auxiliary Aerospace Power

    NASA Technical Reports Server (NTRS)

    Freeh, Joshua E.; Steffen, J., Jr.; Larosiliere, Louis M.

    2005-01-01

    A solid-oxide fuel cell/gas turbine hybrid system for auxiliary aerospace power is analyzed using 0-D and 1-D system-level models. The system is designed to produce 440 kW of net electrical power, sized for a typical long-range 300-passenger civil airplane, at both sea level and cruise flight level (12,500 m). In addition, a part power level of 250 kW is analyzed at the cruise condition, a requirement of the operating power profile. The challenge of creating a balanced system for the three distinct conditions is presented, along with the compromises necessary for each case. A parametric analysis is described for the cruise part power operating point, in which the system efficiency is maximized by varying the air flow rate. The system is compared to an earlier version that was designed solely for cruise operation. The results show that it is necessary to size the turbomachinery, fuel cell, and heat exchangers at sea level full power rather than cruise full power. The resulting estimated mass of the system is 1912 kg, which is significantly higher than the original cruise design point mass, 1396 kg. The net thermal efficiencies with respect to the fuel LHV are calculated to be 42.4 percent at sea level full power, 72.6 percent at cruise full power, and 72.8 percent at cruise part power. The cruise conditions take advantage of pre-compressed air from the on-board Environmental Control System, which accounts for a portion of the unusually high thermal efficiency at those conditions. These results show that it is necessary to include several operating points in the overall assessment of an aircraft power system due to the variations throughout the operating profile.

  15. Solid oxide fuel cell systems for residential micro-combined heat and power in the UK: Key economic drivers

    NASA Astrophysics Data System (ADS)

    Hawkes, Adam; Leach, Matthew

    The ability of combined heat and power (CHP) to meet residential heat and power demands efficiently offers potentially significant financial and environmental advantages over centralised power generation and heat-provision through natural-gas fired boilers. A solid oxide fuel cell (SOFC) can operate at high overall efficiencies (heat and power) of 80-90%, offering an improvement over centralised generation, which is often unable to utilise waste heat. This paper applies an equivalent annual cost (EAC) minimisation model to a residential solid oxide fuel cell CHP system to determine what the driving factors are behind investment in this technology. We explore the performance of a hypothetical SOFC system—representing expectations of near to medium term technology development—under present UK market conditions. We find that households with small to average energy demands do not benefit from installation of a SOFC micro-CHP system, but larger energy demands do benefit under these conditions. However, this result is sensitive to a number of factors including stack capital cost, energy import and export prices, and plant lifetime. The results for small and average dwellings are shown to reverse under an observed change in energy import prices, an increase in electricity export price, a decrease in stack capital costs, or an improvement in stack lifetime.

  16. Experimental and simulated investigation of 1 kW solid oxide fuel cell balance of power system

    NASA Astrophysics Data System (ADS)

    Hong, Sung Kook; Dong, Sang Keun; Yang, Je Bok

    2012-09-01

    A 1 kW solid oxide fuel cell (SOFC) balance of power (BOP) system is analyzed using experiments and simulations to optimize the design and operating conditions. The system consists of an autothermal reformer, combined heat exchanger and afterburner, and dummy stack. Thermolib program is used for the simulations. The system exhibits stable operation during a two cycle on/off experiment. The simulated results obtained by zero-dimensional modeling are similar to the experimental results although a discrepancy appears early in operation owing to the simplified modeling. The system's characteristics are also investigated in terms of the fuel utilization, presence or absence of internal reforming and external heat transfer coefficient.

  17. Alkaline fuel cells applications

    NASA Astrophysics Data System (ADS)

    Kordesch, Karl; Hacker, Viktor; Gsellmann, Josef; Cifrain, Martin; Faleschini, Gottfried; Enzinger, Peter; Fankhauser, Robert; Ortner, Markus; Muhr, Michael; Aronson, Robert R.

    On the world-wide automobile market technical developments are increasingly determined by the dramatic restriction on emissions as well as the regimentation of fuel consumption by legislation. Therefore there is an increasing chance of a completely new technology breakthrough if it offers new opportunities, meeting the requirements of resource preservation and emission restrictions. Fuel cell technology offers the possibility to excel in today's motive power techniques in terms of environmental compatibility, consumer's profit, costs of maintenance and efficiency. The key question is economy. This will be decided by the costs of fuel cell systems if they are to be used as power generators for future electric vehicles. The alkaline hydrogen-air fuel cell system with circulating KOH electrolyte and low-cost catalysed carbon electrodes could be a promising alternative. Based on the experiences of Kordesch [K. Kordesch, Brennstoffbatterien, Springer, Wien, 1984, ISBN 3-387-81819-7; K. Kordesch, City car with H 2-air fuel cell and lead-battery, SAE Paper No. 719015, 6th IECEC, 1971], who operated a city car hybrid vehicle on public roads for 3 years in the early 1970s, improved air electrodes plus new variations of the bipolar stack assembly developed in Graz are investigated. Primary fuel choice will be a major issue until such time as cost-effective, on-board hydrogen storage is developed. Ammonia is an interesting option. The whole system, ammonia dissociator plus alkaline fuel cell (AFC), is characterised by a simple design and high efficiency.

  18. CLIMATE CHANGE FUEL CELL PROGRAM

    SciTech Connect

    Steven A. Gabrielle

    2004-12-03

    This report discusses the first year of operation of a fuel cell power plant located at the Sheraton Edison Hotel, Edison, New Jersey. PPL EnergyPlus, LLC installed the plant under a contract with the Starwood Hotels & Resorts Worldwide, Inc. A DFC{reg_sign}300 fuel cell, manufactured by FuelCell Energy, Inc. of Danbury, CT was selected for the project. The fuel cell successfully operated from June 2003 to May 2004. This report discusses the performance of the plant during this period.

  19. Fuel cell generator energy dissipator

    SciTech Connect

    Veyo, S.E.; Dederer, J.T.; Gordon, J.T.; Shockling, L.A.

    2000-02-15

    An apparatus and method are disclosed for eliminating the chemical energy of fuel remaining in a fuel cell generator when the electrical power output of the fuel cell generator is terminated. During a generator shut down condition, electrically resistive elements are automatically connected across the fuel cell generator terminals in order to draw current, thereby depleting the fuel inventory in the generator. The invention provides a safety function in eliminating the fuel energy, and also provides protection to the fuel cell stack by eliminating overheating.

  20. Fuel Cell Seminar, 1992: Program and abstracts

    SciTech Connect

    Not Available

    1992-12-31

    This year`s theme, ``Fuel Cells: Realizing the Potential,`` focuses on progress being made toward commercial manufacture and use of fuel cell products. Fuel cell power plants are competing for market share in some applications and demonstrations of market entry power plants are proceeding for additional applications. Development activity on fuel cells for transportation is also increasing; fuel cell products have potential in energy and transportation industries, with very favorable environmental impacts. This Seminar has the purpose of fostering communication by providing a forum for the international community interested in development, application, and business opportunities related fuel cells. Over 190 technical papers are included, the majority being processed for the data base.

  1. Environmental and economic assessment of a cracked ammonia fuelled alkaline fuel cell for off-grid power applications

    NASA Astrophysics Data System (ADS)

    Cox, Brian; Treyer, Karin

    2015-02-01

    Global mobile telecommunication is possible due to millions of Base Transceiver Stations (BTS). Nearly 1 million of these are operating off-grid, typically powered by diesel generators and therefore leading to significant CO2 emissions and other environmental burdens. A novel type of Alkaline Fuel Cell (AFC) powered by cracked ammonia is being developed for replacement of these generators. This study compares the environmental and economic performance of the two systems by means of Life Cycle Assessment (LCA) and Levelised Cost of Electricity (LCOE), respectively. Results show that the production of ammonia dominates the LCA results, and that renewable ammonia production pathways greatly improve environmental performance. Sensitivity analyses reveal that the fuel cell parameters that most affect system cost and environmental burdens are cell power density and lifetime and system efficiency. Recycling of anode catalyst and electrode substrate materials is found to have large impacts on environmental performance, though without large cost incentives. For a set of target parameter values and fossil sourced ammonia, the AFC is calculated to produce electricity with life cycle CO2 eq emissions of 1.08 kg kWh-1, which is 23% lower than a diesel generator with electricity costs that are 14% higher in the same application.

  2. Study on Use of Fuel-Cell Auxiliary Power Units in Refrigerator Cars Employed for Delivery to Convenience Store

    NASA Astrophysics Data System (ADS)

    Katayama, Noboru; Kamiyama, Hideyuki; Kogoshi, Sumio; Kudo, Yusuke; Fukada, Takafumi; Ogawa, Makoto

    The use of fuel-cell auxiliary power units (FC-APU) in refrigerator cars employed delivery to for convenience store delivery has been studied. The delivery pattern is assumed to be a typical pattern that includes driving between convenience stores or between a delivery center and a convenience store, unloading, driver's lunch break. The M15 driving mode, which simulates the driving condition in urban areas, is used as the driving mode in the delivery pattern. The FC-APU system includes a proton-exchange membrane fuel cell (PEFC) module, an inverter, and DC/DC converter. Bench tests of the FC-APU are performed to determine the hydrogen fuel consumption rate and the energy efficiency; these values depend on the output power of the PEFC module. The calculated relationship between the output power and fuel consumption rate of a current used system, which consists of an alternator and a secondary battery, are used to estimate the energy efficiency of the current used system. On the basis of the measurement data in this study and the results for the model proposed by Brodric et al. [C. J. Brodrick et al., Trans. Res. D, vol 7, pp. 303 (2002)], the payback period is calculated. The results indicate that the payback period would be 2.1 years when the FC-APU operates at a load of 70%.

  3. Status of commercial phosphoric acid fuel cell power plant system development

    NASA Technical Reports Server (NTRS)

    Warshay, M.

    1987-01-01

    A technology development and commercial feasibility evaluation is presented for phosphoric acid fuel cells (PAFCs) applicable to electric utility operations. The correction of identified design deficiencies in the control card and water treatment subsystems is projected to be able to substantially increase average powerplant availability from the 63 percent achieved in recent field tests of a PAFC system. Current development work is proceeding under NASA research contracts at the output levels of a multimegawatt facility for electric utility use, a multikilowatt on-site integrated energy generation facility, and advanced electrocatalysts applicable to PAFCs.

  4. Fuel cells: A handbook

    NASA Astrophysics Data System (ADS)

    Kinoshita, K.; McLarnon, F. R.; Cairns, E. J.

    1988-05-01

    The purpose of this handbook is to present information describing fuel cells that is helpful to scientists, engineers, and technical managers who are not experienced in this technology, as well as to provide an update on the current technical status of the various types of fuel cells. Following the introduction, contents of this handbook are: fuel cell performance variables; phosphoric acid fuel cell; molten carbonate fuel cell; solid oxide fuel cell; alternative fuel cell technologies; fuel cell systems; and concluding remarks.

  5. Limitations of Commercializing Fuel Cell Technologies

    NASA Astrophysics Data System (ADS)

    Nordin, Normayati

    2010-06-01

    Fuel cell is the technology that, nowadays, is deemed having a great potential to be used in supplying energy. Basically, fuel cells can be categorized particularly by the kind of employed electrolyte. Several fuel cells types which are currently identified having huge potential to be utilized, namely, Solid Oxide Fuel Cells (SOFC), Molten Carbonate Fuel Cells (MCFC), Alkaline Fuel Cells (AFC), Phosphoric Acid Fuel Cells (PAFC), Polymer Electron Membrane Fuel Cell (PEMFC), Direct Methanol Fuel Cells (DMFC) and Regenerative Fuel Cells (RFC). In general, each of these fuel cells types has their own characteristics and specifications which assign the capability and suitability of them to be utilized for any particular applications. Stationary power generations and transport applications are the two most significant applications currently aimed for the fuel cell market. It is generally accepted that there are lots of advantages if fuel cells can be excessively commercialized primarily in context of environmental concerns and energy security. Nevertheless, this is a demanding task to be accomplished, as there is some gap in fuel cells technology itself which needs a major enhancement. It can be concluded, from the previous study, cost, durability and performance are identified as the main limitations to be firstly overcome in enabling fuel cells technology become viable for the market.

  6. Compact methanol reformer test for fuel-cell powered light-duty vehicles

    NASA Astrophysics Data System (ADS)

    Emonts, B.; Bøgild Hansen, J.; Lœgsgaard Jørgensen, S.; Höhlein, B.; Peters, R.

    On-board production of hydrogen from methanol based on a steam reformer in connection with the use of low-temperature fuel-cells (PEMFC) is an attractive option as energy conversion unit for light-duty vehicles. A steam reforming process at higher pressures with an external burner offers advantages in comparison to a steam reformer with integrated partial oxidation in terms of total efficiency for electricity production. The main aim of a common project carried out by the Forschungszentrum Jülich (FZJ), Haldor Topsøe A/S (HTAS) and Siemens AG is to design, to construct and to test a steam reformer reactor concept (HTAS) with external catalytic burner (FZJ) as heat source as well as catalysts for heterogeneously catalyzed hydrogen production (HTAS), concepts for gas treatment (HTAS, FZJ) and a low-temperature fuel cell (Siemens). Based on the experimental results obtained so far concerning methanol reformers, catalytic burners and gas conditioning units, our report describes the total system, a test unit and preliminary test results related to a hydrogen production capacity of 50 kW (LHV) and dynamic operating conditions. This hydrogen production system is aimed at reducing the specific weight (<2 kg/kWth or 4 kg/kWel) combined with high efficiency for net electricity generation from methanol (about 50%) and low specific emissions. The application of Pd-membranes as gas cleaning unit fulfill the requirements with high hydrogen permeability and low cost of the noble metal.

  7. Hydrogen fuel reforming in a fog cooled fuel cell power plant assembly

    SciTech Connect

    Levy, A.H.; Wertheim, R.J.

    1989-09-12

    This patent describes a high pressure phosphoric acid fuel cell stack assembly. The cell comprising: a stack of fuel cells for producing electricity. The stack including cathode means, anode means, and the stack being formed without a separate cooling system; means for delivering a pressurized air supply to the cathode means; means for delivering a hydrogen rich fuel gas to the anode means for electrochemically reacting with oxygen in the pressurized air to produce electricity and water; first exhaust means for removing a mixture of oxygen-depleted air and product water from the cathode means; means for delivering a water fog stream to the anode means for mixture with the hydrogen rich fuel gas. The water fog stream being evaporated in the anode means to cool the stack; means for exhausting a mixture of hydrogen-depleted gas and water vapor from the anode means; reformer means for reforming a raw hydrocarbon fuel to the hydrogen rich fuel gas; and means for delivering the mixture of hydrogen-depleted exhaust gas and water vapor to the reformer means to provide water for the reforming reaction.

  8. Direct Methanol Fuel Cell Power Supply For All-Day True Wireless Mobile Computing

    SciTech Connect

    Brian Wells

    2008-11-30

    PolyFuel has developed state-of-the-art portable fuel cell technology for the portable computing market. A novel approach to passive water recycling within the MEA has led to significant system simplification and size reduction. Miniature stack technology with very high area utilization and minimalist seals has been developed. A highly integrated balance of plant with very low parasitic losses has been constructed around the new stack design. Demonstration prototype systems integrated with laptop computers have been shown in recent months to leading OEM computer manufacturers. PolyFuel intends to provide this technology to its customers as a reference design as a means of accelerating the commercialization of portable fuel cell technology. The primary goal of the project was to match the energy density of a commercial lithium ion battery for laptop computers. PolyFuel made large strides against this goal and has now demonstrated 270 Wh/liter compared with lithium ion energy densities of 300 Wh/liter. Further, more incremental, improvements in energy density are envisioned with an additional 20-30% gains possible in each of the next two years given further research and development.

  9. Distillate fuel-oil processing for phosphoric acid fuel-cell power plants

    SciTech Connect

    Ushiba, K. K.

    1980-02-01

    The current efforts to develop distillate oil-steam reforming processes are reviewed, and the applicability of these processes for integration with the fuel cell are discussed. The development efforts can be grouped into the following processing approaches: high-temperature steam reforming (HTSR); autothermal reforming (ATR); autothermal gasification (AG); and ultra desulfurization followed by steam reforming. Sulfur in the feed is a key problem in the process development. A majority of the developers consider sulfur as an unavoidable contaminant of distillate fuel and are aiming to cope with it by making the process sulfur-tolerant. In the HTSR development, the calcium aluminate catalyst developed by Toyo Engineering represents the state of the art. United Technology (UTC), Engelhard, and Jet Propulsion Laboratory (JPL) are also involved in the HTSR research. The ATR of distillate fuel is investigated by UTC and JPL. The autothermal gasification (AG) of distillate fuel is being investigated by Engelhard and Siemens AG. As in the ATR, the fuel is catalytically gasified utilizing the heat generated by in situ partial combustion of feed, however, the goal of the AG is to accomplish the initial breakdown of the feed into light gases and not to achieve complete conversion to CO and H/sub 2/. For the fuel-cell integration, a secondary reforming of the light gases from the AG step is required. Engelhard is currently testing a system in which the effluent from the AG section enters the steam-reforming section, all housed in a single vessel. (WHK)

  10. Integrated Fuel Cell/Coal Gasifier

    NASA Technical Reports Server (NTRS)

    Ferrall, J. F.

    1985-01-01

    Powerplant design with low-temperature coal gasifier coupled to highly-exothermic fuel cell for efficient production of dc power eliminates need for oxygen in gasifier and achieves high fuel efficiency with recycling of waste heat from fuel cell.

  11. Silver-chlorine fuel cell: A concept

    NASA Technical Reports Server (NTRS)

    Lieberman, M.

    1972-01-01

    Fuel cell regenerated by photochemical reduction enables novel slurry system to transport particles of reduced silver between regenerator section and anode. Fundamental reactions which provide electrical power from the fuel cell are given.

  12. Energy 101: Fuel Cell Technology

    ScienceCinema

    None

    2014-06-06

    Learn how fuel cell technology generates clean electricity from hydrogen to power our buildings and transportation-while emitting nothing but water. This video illustrates the fundamentals of fuel cell technology and its potential to supply our homes, offices, industries, and vehicles with sustainable, reliable energy.

  13. Energy 101: Fuel Cell Technology

    SciTech Connect

    2014-03-11

    Learn how fuel cell technology generates clean electricity from hydrogen to power our buildings and transportation-while emitting nothing but water. This video illustrates the fundamentals of fuel cell technology and its potential to supply our homes, offices, industries, and vehicles with sustainable, reliable energy.

  14. An investigation of a carbon dioxide-based fuel cell system as a power generation alternative for Mars exploration applications

    NASA Astrophysics Data System (ADS)

    Salinas Mejia, Oscar Roberto

    The possibility of using a bifunctional carbon dioxide-based fuel cell system as the core of a propulsion system for a Mars exploration rotorcraft is investigated here. This concept involves the production of electricity by a stack of fuel cells that rely on carbon monoxide as the fuel and oxygen as the oxidizer. These two reactants are harvested from the Martian atmosphere by employing the same stack of cells as an electrolyzing unit. The general objectives of this research are to: prove the feasibility of the concept, produce a comprehensive model that allows the prediction of performance, and offer recommendations for the successful implementation of the concept. In this work, it is pointed out and demonstrated that, at least in theory, the overall electrochemical reaction required by this concept can be achieved by transporting hydrogen protons, hydroxyl radicals, carbonate radicals, or oxygen ions between the electrodes. Complete sets of reactions are prescribed for different types of fuel cells. Anodic and cathodic reactions are presented for acid, alkaline, carbonate, and solid oxide electrolytes. Subsequently, a more detailed consideration of all relevant phenomena is done by coupling elements of chemical kinetics, electrodics, electrochemistry, and thermodynamics with experimental data, to complete the demonstration of the feasibility of the carbon dioxide-based bifunctional fuel cell system. The understanding and inclusion of key processes and mechanisms allows the construction of a model that predicts the performance of the power generation subsystem advocated here. The model adopted in this work couples mechanistics with elements derived from the application of linear regression modeling techniques. Mechanistics are used to determine: thermodynamic equilibrium potential, overvoltages due to activation, ohmic resistance, and mass transport. This approach is empirical in part because the numerical parametric expressions suggested here have to be precised

  15. Fuel cell technology program

    NASA Technical Reports Server (NTRS)

    1972-01-01

    A program to advance the technology for a cost-effective hydrogen/oxygen fuel cell system for future manned spacecraft is discussed. The evaluation of base line design concepts and the development of product improvements in the areas of life, power, specific weight and volume, versatility of operation, field maintenance and thermal control were conducted from the material and component level through the fabrication and test of an engineering model of the fuel cell system. The program was to be accomplished in a 13 month period.

  16. Thermodynamic analysis of a combined gas turbine power plant with a solid oxide fuel cell for marine applications

    NASA Astrophysics Data System (ADS)

    Welaya, Yousri M. A.; Mosleh, M.; Ammar, Nader R.

    2013-12-01

    Strong restrictions on emissions from marine power plants (particularly SOx, NOx) will probably be adopted in the near future. In this paper, a combined solid oxide fuel cell (SOFC) and gas turbine fuelled by natural gas is proposed as an attractive option to limit the environmental impact of the marine sector. It includes a study of a heatrecovery system for 18 MW SOFC fuelled by natural gas, to provide the electric power demand onboard commercial vessels. Feasible heat-recovery systems are investigated, taking into account different operating conditions of the combined system. Two types of SOFC are considered, tubular and planar SOFCs, operated with either natural gas or hydrogen fuels. This paper includes a detailed thermodynamic analysis for the combined system. Mass and energy balances are performed, not only for the whole plant but also for each individual component, in order to evaluate the thermal efficiency of the combined cycle. In addition, the effect of using natural gas as a fuel on the fuel cell voltage and performance is investigated. It is found that a high overall efficiency approaching 70% may be achieved with an optimum configuration using SOFC system under pressure. The hybrid system would also reduce emissions, fuel consumption, and improve the total system efficiency.

  17. Energy analysis of a combined solid oxide fuel cell with a steam turbine power plant for marine applications

    NASA Astrophysics Data System (ADS)

    Welaya, Yousri M. A.; Mosleh, M.; Ammar, Nader R.

    2013-12-01

    Strong restrictions on emissions from marine power plants (particularly SO x , NO x ) will probably be adopted in the near future. In this paper, a combined solid oxide fuel cell (SOFC) and steam turbine fuelled by natural gas is proposed as an attractive option to limit the environmental impact of the marine sector. The analyzed variant of the combined cycle includes a SOFC operated with natural gas fuel and a steam turbine with a single-pressure waste heat boiler. The calculations were performed for two types of tubular and planar SOFCs, each with an output power of 18 MW. This paper includes a detailed energy analysis of the combined system. Mass and energy balances are performed not only for the whole plant but also for each component in order to evaluate the thermal efficiency of the combined cycle. In addition, the effects of using natural gas as a fuel on the fuel cell voltage and performance are investigated. It has been found that a high overall efficiency approaching 60% may be achieved with an optimum configuration using the SOFC system. The hybrid system would also reduce emissions, fuel consumption, and improve the total system efficiency.

  18. Evolutionary programming-based methodology for economical output power from PEM fuel cell for micro-grid application

    NASA Astrophysics Data System (ADS)

    El-Sharkh, M. Y.; Rahman, A.; Alam, M. S.

    This paper presents a methodology for finding the optimal output power from a PEM fuel cell power plant (FCPP). The FCPP is used to supply power to a small micro-grid community. The technique used is based on evolutionary programming (EP) to find a near-optimal solution of the problem. The method incorporates the Hill-Climbing technique (HCT) to maintain feasibility during the solution process. An economic model of the FCPP is used. The model considers the production cost of energy and the possibility of selling and buying electrical energy from the local grid. In addition, the model takes into account the thermal energy output from the FCPP and the thermal energy requirement for the micro-grid community. The results obtained are compared against a solution based on genetic algorithms. Results are encouraging and indicate viability of the proposed technique.

  19. Fuel cell cogeneration

    SciTech Connect

    Wimer, J.G.; Archer, D.

    1995-08-01

    The U.S. Department of Energy`s Morgantown Energy Technology Center (METC) sponsors the research and development of engineered systems which utilize domestic fuel supplies while achieving high standards of efficiency, economy, and environmental performance. Fuel cell systems are among the promising electric power generation systems that METC is currently developing. Buildings account for 36 percent of U.S. primary energy consumption. Cogeneration systems for commercial buildings represent an early market opportunity for fuel cells. Seventeen percent of all commercial buildings are office buildings, and large office buildings are projected to be one of the biggest, fastest-growing sectors in the commercial building cogeneration market. The main objective of this study is to explore the early market opportunity for fuel cells in large office buildings and determine the conditions in which they can compete with alternative systems. Some preliminary results and conclusions are presented, although the study is still in progress.

  20. Microfluidic fuel cells

    NASA Astrophysics Data System (ADS)

    Kjeang, Erik

    Microfluidic fuel cell architectures are presented in this thesis. This work represents the mechanical and microfluidic portion of a microfluidic biofuel cell project. While the microfluidic fuel cells developed here are targeted to eventual integration with biocatalysts, the contributions of this thesis have more general applicability. The cell architectures are developed and evaluated based on conventional non-biological electrocatalysts. The fuel cells employ co-laminar flow of fuel and oxidant streams that do not require a membrane for physical separation, and comprise carbon or gold electrodes compatible with most enzyme immobilization schemes developed to date. The demonstrated microfluidic fuel cell architectures include the following: a single cell with planar gold electrodes and a grooved channel architecture that accommodates gaseous product evolution while preventing crossover effects; a single cell with planar carbon electrodes based on graphite rods; a three-dimensional hexagonal array cell based on multiple graphite rod electrodes with unique scale-up opportunities; a single cell with porous carbon electrodes that provides enhanced power output mainly attributed to the increased active area; a single cell with flow-through porous carbon electrodes that provides improved performance and overall energy conversion efficiency; and a single cell with flow-through porous gold electrodes with similar capabilities and reduced ohmic resistance. As compared to previous results, the microfluidic fuel cells developed in this work show improved fuel cell performance (both in terms of power density and efficiency). In addition, this dissertation includes the development of an integrated electrochemical velocimetry approach for microfluidic devices, and a computational modeling study of strategic enzyme patterning for microfluidic biofuel cells with consecutive reactions.

  1. Develop and test fuel cell powered on-site integrated total energy system. Phase 3: Full-scale power plant development

    NASA Technical Reports Server (NTRS)

    Kaufman, A.

    1981-01-01

    An integrated 5 kW power system based upon methanol fuel and a phosphoric acid fuel cell operating at about 473 K is described. Description includes test results of advanced fuel cell catalysts, a semiautomatic acid replenishment system and a completed 5 kW methanol/system reformer. The results of a preliminary system test on a reformer/stack/inverter combination are reported. An initial design for a 25 kW stack is presented. Experimental plans are outlined for data acquisition necessary for design of a 50 kW methanol/steam reformer. Activities related to complete mathematical modelling of the integrated power system, including wasteheat utilization, are described.

  2. Use of carbon mesh anodes and the effect of different pretreatment methods on power production in microbial fuel cells.

    PubMed

    Wang, Xin; Cheng, Shaoan; Feng, Yujie; Merrill, Matthew D; Saito, Tomonori; Logan, Bruce E

    2009-09-01

    Flat electrodes are useful in microbial fuel cells (MFCs) as close electrode spacing improves power generation. Carbon cloth and carbon paper materials typically used in hydrogen fuel cells, however, are prohibitively expensive for use in MFCs. An inexpensive carbon mesh material was examined here as a substantially less expensive alternative to these materials for the anode in an MFC. Pretreatment of the carbon mesh was needed to ensure adequate MFC performance. Heating the carbon mesh in a muffle furnace (450 degrees C for 30 min) resulted in a maximum power density of 922 mW/m2 (46 W/m3) with this heat-treated anode, which was 3% more power than that produced using a mesh anode cleaned with acetone (893 mW/ m2; 45 W/m3). This power density with heating was only 7% less than that achieved with carbon cloth treated by a high temperature ammonia gas process (988 mW/m2; 49 W/m3). When the carbon mesh was treated by the ammonia gas process, power increased to 1015 mW/m2(51 W/m3). Analysis of the cleaned or heated surfaces showed these processes decreased atomic O/C ratio, indicating removal of contaminants that interfered with charge transfer. Ammonia gas treatment also increased the atomic N/C ratio, suggesting that this process produced nitrogen related functional groups that facilitated electron transfer. These results show that low cost heat-treated carbon mesh materials can be used as the anode in an MFC, providing good performance and even exceeding performance of carbon cloth anodes. PMID:19764262

  3. Performance of electric forklift with low-temperature polymer exchange membrane fuel cell power module and metal hydride hydrogen storage extension tank

    NASA Astrophysics Data System (ADS)

    Lototskyy, Mykhaylo V.; Tolj, Ivan; Parsons, Adrian; Smith, Fahmida; Sita, Cordellia; Linkov, Vladimir

    2016-06-01

    We present test results of a commercial 3-tonne electric forklift (STILL) equipped with a commercial fuel cell power module (Plug Power) and a MH hydrogen storage tank (HySA Systems and TF Design). The tests included: (i) performance evaluation of "hybrid" hydrogen storage system during refuelling at low (<185 bar) dispensing pressures; (ii) comparison of the forklift performances during heavy-duty operation when changing the powering in the series: standard battery - fuel cell power module (alone) - power module with integrated MH tank; and (iii) performance tests of the forklift during its operation under working conditions. It was found that (a) the forklift with power module and MH tank can achieve 83% of maximum hydrogen storage capacity during 6 min refuelling (for full capacity 12-15 min); (b) heavy-duty operation of the forklift is characterised by 25% increase in energy consumption, and during system operation more uniform power distribution occurs when operating in the fuel cell powering mode with MH, in comparison to the battery powering mode; (c) use of the fully refuelled fuel cell power module with the MH extension tank allows for uninterrupted operation for 3 h 6 min and 7 h 15 min, for heavy- and light-duty operation, respectively.

  4. Microbial fuel cells - Applications for generation of electrical power and beyond.

    PubMed

    Mathuriya, Abhilasha Singh; Yakhmi, J V

    2016-01-01

    A Microbial Fuel Cell is a bioelectrochemical device that exploits metabolic activities of living microorganisms for generation of electric current. The usefulness and unique and exclusive architecture of this device has received wide attention recently of engineers and researchers of various disciplines such as microbiologists, chemical engineers, biotechnologists, environment engineers and mechanical engineers, and the subject of MFCs has thereby progressed as a well-developed technology. Sustained innovations and continuous development efforts have established the usefulness of MFCs towards many specialized and value-added applications beyond electricity generation, such as wastewater treatment and implantable body devices. This review is an attempt to provide an update on this rapidly growing technology. PMID:24903308

  5. Cost-effective copper removal by electrosorption powered by microbial fuel cells.

    PubMed

    Yang, Jie; Zhou, Minghua; Hu, Youshuang; Yang, Weilu

    2016-03-01

    This work studied a cost-effective electrosorption that driven by microbial fuel cells (MFC-sorption) to remove Cu(2+) from wastewater without an external energy supply. The impact factors, adsorption isotherms and kinetics of the novel process were investigated. It indicated that a low electrolyte concentration and a high solution pH could enhance the Cu(2+) removal efficiency, while the adsorption capacity increased with the increase of numbers of MFCs in series and the initial Cu(2+) concentration. The adsorption isotherms study indicated that the monolayer adsorption in MFC-sorption was dominant. The kinetics study suggested the increase of initial Cu(2+) concentration could enhance the initial adsorption rate. The electrode characterizations verified the existence of Cu2O and Cu on the electrode surface of active carbon fibers (ACFs), suggesting that MFC-sorption was not only an adsorption process, but also a redox reaction process. PMID:26747441

  6. Evaluation of Gas-Cooled Pressurized Phosphoric Acid Fuel Cells for Electric Utility Power Generation

    NASA Technical Reports Server (NTRS)

    Faroque, M.

    1983-01-01

    Gas cooling is a more reliable, less expensive and a more simple alternative to conventional liquid cooling for heat removal from the phosphoric acid fuel cell (PAFC). The feasibility of gas-cooling was already demonstrated in atmospheric pressure stacks. Theoretical and experimental investigations of gas-cooling for pressurized PAFC are presented. Two approaches to gas cooling, Distributed Gas-Cooling (DIGAS) and Separated Gas-Cooling (SGC) were considered, and a theoretical comparison on the basis of cell performance indicated SGC to be superior to DIGAS. The feasibility of SGC was experimentally demonstrated by operating a 45-cell stack for 700 hours at pressure, and determining thermal response and the effect of other related parameters.

  7. Analysis of a Planar Solid Oxide Fuel Cell based Automotive Auxiliary Power Unit

    SciTech Connect

    Keegan, Kevin R.; Khaleel, Mohammad A. ); Chick, Lawrence A. ); Recknagle, Kurtis P. ); Simner, Steve P. ); Deibler, John E. )

    2003-07-01

    The solid oxide fuel cell (SOFC) system has emerged as an important technology for automotive and stationary applications. Modeling and simulation of the SOFC system have been utilized as an integral tool in an accelerated joint SOFC system development program. Development of unique modeling approaches and their results are discussed and compared with experimental performance. One dimensional system level analysis using Aspen with an embedded stack electro-chemical model was performed resulting in effective sub-system partitioning and requirements definition. Further, a three-dimensional integrated electro-chemical/thermal/computational fluid dynamics analysis of steady-state operation was employed. The combination of one-dimensional and three-dimensional environments led to effective performance projection at all levels in the system, resulting in optimization of overall system performance early in the design cycle.

  8. Transient responses of phosphoric acid fuel cell power plant system. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Lu, Cheng-Yi

    1983-01-01

    An analytical and computerized study of the steady state and transient response of a phosphoric acid fuel cell (PAFC) system was completed. Parametric studies and sensitivity analyses of the PAFC system's operation were accomplished. Four non-linear dynamic models of the fuel cell stack, reformer, shift converters, and heat exchangers were developed based on nonhomogeneous non-linear partial differential equations, which include the material, component, energy balance, and electrochemical kinetic features. Due to a lack of experimental data for the dynamic response of the components only the steady state results were compared with data from other sources, indicating reasonably good agreement. A steady state simulation of the entire system was developed using, nonlinear ordinary differential equations. The finite difference method and trial-and-error procedures were used to obtain a solution. Using the model, a PAFC system, that was developed under NASA Grant, NCC3-17, was improved through the optimization of the heat exchanger network. Three types of cooling configurations for cell plates were evaluated to obtain the best current density and temperature distributions. The steady state solutions were used as the initial conditions in the dynamic model. The transient response of a simplified PAFC system, which included all of the major components, subjected to a load change was obtained. Due to the length of the computation time for the transient response calculations, analysis on a real-time computer was not possible. A simulation of the real-time calculations was developed on a batch type computer. The transient response characteristics are needed for the optimization of the design and control of the whole PAFC system. All of the models, procedures and simulations were programmed in Fortran and run on IBM 370 computers at Cleveland State University and the NASA Lewis Research Center.

  9. LOW-TEMPERATURE, ANODE-SUPPORTED HIGH POWER DENSITY SOLID OXIDE FUEL CELLS WITH NANOSTRUCTURED ELECTRODES

    SciTech Connect

    Professor Anil V. Virkar

    2003-05-23

    This report summarizes the work done during the entire project period, between October 1, 1999 and March 31, 2003, which includes a six-month no-cost extension. During the project, eight research papers have, either been, published, accepted for publication, or submitted for publication. In addition, several presentations have been made in technical meetings and workshops. The project also has provided support for four graduate students working towards advanced degrees. The principal technical objective of the project was to analyze the role of electrode microstructure on solid oxide fuel cell performance. Prior theoretical work conducted in our laboratory demonstrated that the particle size of composite electrodes has a profound effect on cell performance; the finer the particle size, the lower the activation polarization, the better the performance. The composite cathodes examined consisted of electronically conducting perovskites such as Sr-doped LaMnO{sub 3} (LSM) or Sr-doped LaCoO{sub 3} (LSC), which is also a mixed conductor, as the electrocatalyst, and yttria-stabilized zirconia (YSZ) or rare earth oxide doped CeO{sub 2} as the ionic conductor. The composite anodes examined were mixtures of Ni and YSZ. A procedure was developed for the synthesis of nanosize YSZ by molecular decomposition, in which unwanted species were removed by leaching, leaving behind nanosize YSZ. Anode-supported cells were made using the as-synthesized powders, or using commercially acquired powders. The electrolyte was usually a thin ({approx}10 microns), dense layer of YSZ, supported on a thick ({approx}1 mm), porous Ni + YSZ anode. The cathode was a porous mixture of electrocatalyst and an ionic conductor. Most of the cell testing was done at 800 C with hydrogen as fuel and air as the oxidant. Maximum power densities as high as 1.8 W/cm{sup 2} were demonstrated. Polarization behavior of the cells was theoretically analyzed. A limited amount of cell testing was done using liquid

  10. 2010 Manufacturing Readiness Assessment Update to the 2008 Report for Fuel Cell Stacks and Systems for the Backup Power and Materials Handling Equipment Markets

    SciTech Connect

    Wheeler, D.; Ulsh, M.

    2012-08-01

    In 2008, the National Renewable Energy Laboratory (NREL), under contract to the US Department of Energy (DOE), conducted a manufacturing readiness assessment (MRA) of fuel cell systems and fuel cell stacks for back-up power and material handling applications (MHE). To facilitate the MRA, manufacturing readiness levels (MRL) were defined that were based on the Technology Readiness Levels previously established by the US Department of Energy (DOE). NREL assessed the extensive existing hierarchy of MRLs developed by Department of Defense (DoD) and other Federal entities, and developed a MRL scale adapted to the needs of the Fuel Cell Technologies Program (FCTP) and to the status of the fuel cell industry. The MRL ranking of a fuel cell manufacturing facility increases as the manufacturing capability transitions from laboratory prototype development through Low Rate Initial Production to Full Rate Production. DOE can use MRLs to address the economic and institutional risks associated with a ramp-up in polymer electrolyte membrane (PEM) fuel cell production. In 2010, NREL updated this assessment, including additional manufacturers, an assessment of market developments since the original report, and a comparison of MRLs between 2008 and 2010.

  11. Sustainable Power Generation in Continuous Flow Microbial Fuel Cell Treating Actual Wastewater: Influence of Biocatalyst Type on Electricity Production

    PubMed Central

    Ismail, Zainab Z.; Jaeel, Ali Jwied

    2013-01-01

    Microbial fuel cells (MFCs) have the potential to simultaneously treat wastewater for reuse and to generate electricity. This study mainly considers the performance of an upflow dual-chambered MFC continuously fueled with actual domestic wastewater and alternatively biocatalyzed with aerobic activated sludge and strain of Bacillus Subtilis. The behavior of MFCs during initial biofilm growth and characterization of anodic biofilm were studied. After 45 days of continuous operation, the biofilms on the anodic electrode were well developed. The performance of MFCs was mainly evaluated in terms of COD reductions and electrical power output. Results revealed that the COD removal efficiency was 84% and 90% and the stabilized power outputs were clearly observed achieving a maximum value of 120 and 270 mW/m2 obtained for MFCs inoculated with mixed cultures and Bacillus Subtilis strain, respectively. PMID:24453893

  12. Engineering aspects and hardware verification of a volume producable solid oxide fuel cell stack design for diesel auxiliary power units

    NASA Astrophysics Data System (ADS)

    Stelter, Michael; Reinert, Andreas; Mai, Björn Erik; Kuznecov, Mihail

    A solid oxide fuel cell (SOFC) stack module is presented that is designed for operation on diesel reformate in an auxiliary power unit (APU). The stack was designed using a top-down approach, based on a specification of an APU system that is installed on board of vehicles. The stack design is planar, modular and scalable with stamped sheet metal interconnectors. It features thin membrane electrode assemblies (MEAs), such as electrolyte supported cells (ESC) and operates at elevated temperatures around 800 °C. The stack has a low pressure drop in both the anode and the cathode to facilitate a simple system layout. An overview of the technical targets met so far is given. A stack power density of 0.2 kW l -1 has been demonstrated in a fully integrated, thermally self-sustaining APU prototype running with diesel and without an external water supply.

  13. Monolithic solid oxide fuel cell technology advancement for coal-based power generation. Final report, September 1989--March 1994

    SciTech Connect

    Not Available

    1994-05-01

    This project has successfully advanced the technology for MSOFCs for coal-based power generation. Major advances include: tape-calendering processing technology, leading to 3X improved performance at 1000 C; stack materials formulations and designs with sufficiently close thermal expansion match for no stack damage after repeated thermal cycling in air; electrically conducting bonding with excellent structural robustness; and sealants that form good mechanical seals for forming manifold structures. A stack testing facility was built for high-spower MSOFC stacks. Comprehensive models were developed for fuel cell performance and for analyzing structural stresses in multicell stacks and electrical resistance of various stack configurations. Mechanical and chemical compatibility properties of fuel cell components were measured; they show that the baseline Ca-, Co-doped interconnect expands and weakens in hydrogen fuel. This and the failure to develop adequate sealants were the reason for performance shortfalls in large stacks. Small (1-in. footprint) two-cell stacks were fabricated which achieved good performance (average area-specific-resistance 1.0 ohm-cm{sup 2} per cell); however, larger stacks had stress-induced structural defects causing poor performance.

  14. Support schemes and ownership structures - the policy context for fuel cell based micro-combined heat and power

    NASA Astrophysics Data System (ADS)

    Schroeder, Sascha Thorsten; Costa, Ana; Obé, Elisabeth

    In recent years, fuel cell based micro-combined heat and power (mCHP) has received increasing attention due to its potential contribution to European energy policy goals, i.e., sustainability, competitiveness and security of supply. Besides technical advances, regulatory framework and ownership structures are of crucial importance in order to achieve greater diffusion of the technology in residential applications. This paper analyses the interplay of policy and ownership structures for the future deployment of mCHP. Furthermore, it regards the three country cases Denmark, France and Portugal. Firstly, the implications of different kinds of support schemes on investment risk and the diffusion of a technology are explained conceptually. Secondly, ownership arrangements are addressed. Then, a cross-country comparison on present support schemes for mCHP and competing technologies discusses the national implementation of European legislation in Denmark, France and Portugal. Finally, resulting implications for ownership arrangements on the choice of support scheme are explained. From a conceptual point of view, investment support, feed-in tariffs and price premiums are the most appropriate schemes for fuel cell mCHP. This can be used for improved analysis of operational strategies. The interaction of this plethora of elements necessitates careful balancing from a private- and socio-economic point of view.

  15. Benthic microbial fuel cell as direct power source for an acoustic modem and seawater oxygen/temperature sensor system.

    PubMed

    Gong, Yanming; Radachowsky, Sage E; Wolf, Michael; Nielsen, Mark E; Girguis, Peter R; Reimers, Clare E

    2011-06-01

    Supported by the natural potential difference between anoxic sediment and oxic seawater, benthic microbial fuel cells (BMFCs) promise to be ideal power sources for certain low-power marine sensors and communication devices. In this study a chambered BMFC with a 0.25 m(2) footprint was used to power an acoustic modem interfaced with an oceanographic sensor that measures dissolved oxygen and temperature. The experiment was conducted in Yaquina Bay, Oregon over 50 days. Several improvements were made in the BMFC design and power management system based on lessons learned from earlier prototypes. The energy was harvested by a dynamic gain charge pump circuit that maintains a desired point on the BMFC's power curve and stores the energy in a 200 F supercapacitor. The system also used an ultralow power microcontroller and quartz clock to read the oxygen/temperature sensor hourly, store data with a time stamp, and perform daily polarizations. Data records were transmitted to the surface by the acoustic modem every 1-5 days after receiving an acoustic prompt from a surface hydrophone. After jump-starting energy production with supplemental macroalgae placed in the BMFC's anode chamber, the average power density of the BMFC adjusted to 44 mW/m(2) of seafloor area which is better than past demonstrations at this site. The highest power density was 158 mW/m(2), and the useful energy produced and stored was ≥ 1.7 times the energy required to operate the system. PMID:21545151

  16. CLIMATE CHANGE FUEL CELL PROGRAM

    SciTech Connect

    Mike Walneuski

    2004-09-16

    ChevronTexaco has successfully operated a 200 kW PC25C phosphoric acid fuel cell power plant at the corporate data center in San Ramon, California for the past two years and seven months following installation in December 2001. This site was chosen based on the ability to utilize the combined heat (hot water) and power generation capability of this modular fuel cell power plant in an office park setting . In addition, this project also represents one of the first commercial applications of a stationary fuel cell for a mission critical data center to assess power reliability benefits. This fuel cell power plant system has demonstrated outstanding reliability and performance relative to other comparably sized cogeneration systems.

  17. Towards high power output of scaled-up benthic microbial fuel cells (BMFCs) using multiple electron collectors.

    PubMed

    Liu, Bingchuan; Williams, Isaiah; Li, Yan; Wang, Lei; Bagtzoglou, Amvrossios; McCutcheon, Jeffrey; Li, Baikun

    2016-05-15

    This study aimed at achieving high power output of benthic microbial fuel cells (BMFCs) with novel geometric anode setups (inverted tube granular activated charcoal (IT-GAC) and carbon cloth roll (CCR)) and multiple anodes/electron collectors. The lab-scale tests showed the power density of IT-GAC and CCR anodes achieved at 2.92 and 2.55 W m(-2), the highest value ever reported in BMFCs. The power density of BMFCs substantially increased with electron collector number (titanium rods) in anodes. The connection of multiple electron collectors with multiple cathodes had much higher total voltage/current output than that with single cathode. The possibility of maintaining high power density at scaled-up BMFCs was explored by arranging multiple anodes in sediment. The compact configuration of multiple CCR anodes contacting each other did not deteriorate the performance of individual anodes, showing the feasibility of maximizing anode numbers per sediment footprint and achieving high power output. Multiple IT-GAC and CCR anodes with multiple collectors effectively utilized sediment at both horizontal and vertical directions and enhanced electron collection efficiency. This study demonstrated that bacterial adhesion and electron collection should be optimized on small anodes in order to maintain high power density and achieve high power output in the scaled-up BMFCs. PMID:26745789

  18. FUEL CELL ENERGY RECOVERY FROM LANDFILL GAS

    EPA Science Inventory

    International Fuel Cells Corporation is conducting a US Environmental Protection Agency (EPA) sponsored program to demonstrate energy recovery from landfill gas using a commercial phosphoric acid fuel cell power plant. The US EPA is interested in fuel cells for this application b...

  19. Separation of gaseous hydrogen from a water-hydrogen mixture in a fuel cell power system operating in a weightless environment

    NASA Technical Reports Server (NTRS)

    Romanowski, William E. (Inventor); Suljak, George T. (Inventor)

    1989-01-01

    A fuel cell power system for use in a weightless environment, such as in space, includes a device for removing water from a water-hydrogen mixture condensed from the exhaust from the fuel cell power section of the system. Water is removed from the mixture in a centrifugal separator, and is fed into a holding, pressure operated water discharge valve via a Pitot tube. Entrained nondissolved hydrogen is removed from the Pitot tube by a bleed orifice in the Pitot tube before the water reaches the water discharge valve. Water discharged from the valve thus has a substantially reduced hydrogen content.

  20. Climate Change Fuel Cell Program

    SciTech Connect

    Paul Belard

    2006-09-21

    Verizon is presently operating the largest Distributed Generation Fuel Cell project in the USA. Situated in Long Island, NY, the power plant is composed of seven (7) fuel cells operating in parallel with the Utility grid from the Long Island Power Authority (LIPA). Each fuel cell has an output of 200 kW, for a total of 1.4 mW generated from the on-site plant. The remaining power to meet the facility demand is purchased from LIPA. The fuel cell plant is utilized as a co-generation system. A by-product of the fuel cell electric generation process is high temperature water. The heat content of this water is recovered from the fuel cells and used to drive two absorption chillers in the summer and a steam generator in the winter. Cost savings from the operations of the fuel cells are forecasted to be in excess of $250,000 per year. Annual NOx emissions reductions are equivalent to removing 1020 motor vehicles from roadways. Further, approximately 5.45 million metric tons (5 millions tons) of CO2 per year will not be generated as a result of this clean power generation. The project was partially financed with grants from the New York State Energy R&D Authority (NYSERDA) and from Federal Government Departments of Defense and Energy.

  1. Utilization of a fuel cell power plant for the capture and conversion of gob well gas. Final report, June--December, 1995

    SciTech Connect

    Przybylic, A.R.; Haynes, C.D.; Haskew, T.A.; Boyer, C.M. II; Lasseter, E.L.

    1995-12-01

    A preliminary study has been made to determine if a 200 kW fuel cell power plant operating on variable quality coalbed methane can be placed and successfully operated at the Jim Walter Resources No. 4 mine located in Tuscaloosa County, Alabama. The purpose of the demonstration is to investigate the effects of variable quality (50 to 98% methane) gob gas on the output and efficiency of the power plant. To date, very little detail has been provided concerning the operation of fuel cells in this environment. The fuel cell power plant will be located adjacent to the No. 4 mine thermal drying facility rated at 152 M British thermal units per hour. The dryer burns fuel at a rate of 75,000 cubic feet per day of methane and 132 tons per day of powdered coal. The fuel cell power plant will provide 700,000 British thermal units per hour of waste heat that can be utilized directly in the dryer, offsetting coal utilization by approximately 0.66 tons per day and providing an avoided cost of approximately $20 per day. The 200 kilowatt electrical power output of the unit will provide a utility cost reduction of approximately $3,296 each month. The demonstration will be completely instrumented and monitored in terms of gas input and quality, electrical power output, and British thermal unit output. Additionally, real-time power pricing schedules will be applied to optimize cost savings. 28 refs., 35 figs., 13 tabs.

  2. Demonstration of a Highly Efficient Solid Oxide Fuel Cell Power System Using Adiabatic Steam Reforming and Anode Gas Recirculation

    SciTech Connect

    Powell, Michael R.; Meinhardt, Kerry D.; Sprenkle, Vincent L.; Chick, Lawrence A.; Mcvay, Gary L.

    2012-05-01

    Solid oxide fuel cells (SOFC) are currently being developed for a wide variety of applications because of their high efficiency at multiple power levels. Applications for SOFCs encompass a large range of power levels including 1-2 kW residential combined heat and power applications, 100-250 kW sized systems for distributed generation and grid extension, and MW-scale power plants utilizing coal. This paper reports on the development of a highly efficient, small-scale SOFC power system operating on methane. The system uses adiabatic steam reforming of methane and anode gas recirculation to achieve high net electrical efficiency. The anode exit gas is recirculated and all of the heat and water required for the endothermic reforming reaction are provided by the anode gas emerging from the SOFC stack. Although the single-pass fuel utilization is only about 55%, because of the anode gas recirculation the overall fuel utilization is up to 93%. The demonstrated system achieved gross power output of 1650 to 2150 watts with a maximum net LHV efficiency of 56.7% at 1720 watts. Overall system efficiency could be further improved to over 60% with use of properly sized blowers.

  3. Electrosorption driven by microbial fuel cells to remove phenol without external power supply.

    PubMed

    Yang, Jie; Zhou, Minghua; Zhao, Yingying; Zhang, Chao; Hu, Youshuang

    2013-12-01

    This work studied the operating parameters (pH, electrolyte concentration, initial phenol concentration, MFCs connection numbers and mode), adsorption isotherms and kinetics of a novel electrosorption driven by microbial fuel cells (MFC-Sorption) to remove phenol without external electric grid energy supply. It proved that high electrolyte concentration and low solution pH promoted the performance of phenol removal. 3 MFCs connections in series achieved a adsorption capacity of 1.76 mmol/g, which was much higher than that in parallel connection (1.46 mmol/g). Well fitted with Langmuir isotherm, the maximum adsorption capacity by MFC-Sorption and electrosorption was observed 48% and 65% higher than that by conventional adsorption. The phenol removal by MFC-Sorption was supposed to be more suitable for a pseudo-second-order kinetics, and with the increase of initial phenol concentration from 20 mg/L to 300 mg/L, the initial adsorption rate increased 26.99-fold. It concluded that the MFC-Sorption system could cost-effectively remove pollutant of phenol. PMID:24177161

  4. Development of a UBFC biocatalyst fuel cell to generate power and treat industrial wastewaters.

    PubMed

    Sukkasem, Chontisa; Laehlah, Sunee

    2013-10-01

    Agro-industry wastewaters normally contain high levels of organic matter and require suitable treatment before discharge. The use of Microbial fuel cells, a novel wastewater treatment, can provide advantages over existing treatment methods. In this study, an up-flow bio-filter circuit (UBFC) for treating wastewaters without chemical treatment or nutrient supplement, was developed to solve a clogging problem. The optimal conditions included an organic loading rate of 30.0 g COD/L-d, hydraulic retention time of 1.04 day, pH level of 5.6-6.5 and aeration at 2.0 L/min. External resistance of the circuit was tested. COD removal levels of 8.08, 20.1 and 26.67 g COD/L-d were obtained, while fed with sea food, biodiesel and palm oil mill wastewater, respectively. These rates are higher than for conventional technologies. The carbon fiber brush immobilized base increased the performance of the new UBFC by 17.54% over that obtained in a previous study, while the cost was slightly decreased about 4.48%. PMID:23932287

  5. Numerical modelling of methane-powered micro-tubular, single-chamber solid oxide fuel cell

    NASA Astrophysics Data System (ADS)

    Akhtar, N.; Decent, S. P.; Kendall, K.

    An experimentally validated, two-dimensional, axisymmetric, numerical model of micro-tubular, single-chamber solid oxide fuel cell (MT-SC-SOFC) has been developed. The model incorporates methane full combustion, steam reforming, dry reforming and water-gas shift reaction followed by electrochemical oxidation of produced hydrogen within the anode. On the cathode side, parasitic combustion of methane along with the electrochemical oxygen reduction is implemented. The results show that the poor performance of single-chamber SOFC as compared to the conventional (dual-chamber) SOFC (in case of micro-tubes) is due to the mass transport limitation on the anode side. The gas velocity inside the micro-tube is far too low when compared to the gas-chamber inlet velocity. The electronic current density is also non-uniform over the cell length, mainly due to the short length of the anode current collector located at the cell outlet. Furthermore, the higher temperature near the cell edges is due to the methane combustion (very close to the cell inlet) and current collection point (at the cell outlet). Both of these locations could be sensitive to the silver current collecting wire as silver may rupture due to cell overheating.

  6. LOW-TEMPERATURE, ANODE-SUPPORTED HIGH POWER DENSITY SOLID OXIDE FUEL CELLS WITH NANOSTRUCTURED ELECTRODES

    SciTech Connect

    Prof. Anil V. Virkar

    2000-04-07

    This report contains the following three parts. (1) An investigation into the use of direct liquid hydrocarbon fuels in single cell tests. (2) An analysis of residual stresses in anode-supported solid oxide fuel cells. (3) A manuscript on the synthesis of nanosize ceramic (electrode and electrolyte) powders. Nanosize YSZ powder was prepared by a unique approach, in which yttria-doped BaZrO{sub 3} or yttria-doped Na{sub 2}ZrO{sub 3} precursors were first synthesized by a solid state reaction. Then, then the unwanted species, BaO or Na{sub 2}O, was leached away by washing the precursors in a dilute HNO{sub 3} solution or in water. This led to the formation of very fine, nanosize yttria-stabilized zirconia (YSZ). The particle size of the as-synthesized YSZ powders was a few nanometers and increased to tens of nanometers after thermal treatment at a temperature as high as 1000 C. The as-synthesized as well as heat-treated YSZ powder was of cubic crystal structure.

  7. Defense applications of fuel cells

    NASA Astrophysics Data System (ADS)

    Barthelemy, R. R.

    Applications and developmental efforts by the service branches of the U.S. toward implementation of fuel cells for military purposes are reviewed. The fuel cells are being produced as a petroleum fuel substitute and are foreseen to offer quieter, more efficient power at less expense, with lower logistic problems, and to possess cogeneration potential. Applications are indicated for mobile, remote, facility, and emergency/auxiliary power systems. The systems range from one kilowatt to several MW, and can be interfaced with weapon systems. Research in phosphoric acid fuel cells is noted, as are applications in space, undersea, and in aircraft.

  8. Micro-Tubular Fuel Cells

    NASA Technical Reports Server (NTRS)

    Kimble, Michael C.; Anderson, Everett B.; Jayne, Karen D.; Woodman, Alan S.

    2004-01-01

    Micro-tubular fuel cells that would operate at power levels on the order of hundreds of watts or less are under development as alternatives to batteries in numerous products - portable power tools, cellular telephones, laptop computers, portable television receivers, and small robotic vehicles, to name a few examples. Micro-tubular fuel cells exploit advances in the art of proton-exchange-membrane fuel cells. The main advantage of the micro-tubular fuel cells over the plate-and-frame fuel cells would be higher power densities: Whereas the mass and volume power densities of low-pressure hydrogen-and-oxygen-fuel plate-and-frame fuel cells designed to operate in the targeted power range are typically less than 0.1 W/g and 0.1 kW/L, micro-tubular fuel cells are expected to reach power densities much greater than 1 W/g and 1 kW/L. Because of their higher power densities, micro-tubular fuel cells would be better for powering portable equipment, and would be better suited to applications in which there are requirements for modularity to simplify maintenance or to facilitate scaling to higher power levels. The development of PEMFCs has conventionally focused on producing large stacks of cells that operate at typical power levels >5 kW. The usual approach taken to developing lower-power PEMFCs for applications like those listed above has been to simply shrink the basic plate-and-frame configuration to smaller dimensions. A conventional plate-and-frame fuel cell contains a membrane/electrode assembly in the form of a flat membrane with electrodes of the same active area bonded to both faces. In order to provide reactants to both electrodes, bipolar plates that contain flow passages are placed on both electrodes. The mass and volume overhead of the bipolar plates amounts to about 75 percent of the total mass and volume of a fuel-cell stack. Removing these bipolar plates in the micro-tubular fuel cell significantly increases the power density.

  9. Independent Orbiter Assessment (IOA): Assessment of the electrical power generation/fuel cell powerplant subsystem FMEA/CIL

    NASA Technical Reports Server (NTRS)

    Brown, K. L.; Bertsch, P. J.

    1987-01-01

    Results of the Independent Orbiter Assessment (IOA) of the Failure Modes and Effects Analysis (FMEA) and Critical Items List (CIL) are presented. The IOA effort first completed an analysis of the Electrical Power Generation/Fuel Cell Powerplant (EPG/FCP) hardware, generating draft failure modes and potential critical items. To preserve independence, this analysis was accomplished without reliance upon the results contained within the NASA FMEA/CIL documentation. The IOA results were then compared to the proposed Post 51-L NASA FMEA/CIL baseline. A resolution of each discrepancy from the comparison was provided through additional analysis as required. This report documents the results of that comparison for the Orbiter EPG/FCP hardware.

  10. Use of excess solar array power by regenerative fuel cell energy storage systems in low earth orbit

    SciTech Connect

    Hoberecht, M.A.; Green, R.D.

    1997-12-31

    Regenerative Fuel Cells (RFC`s) are a competing energy storage system technology for a number of low-earth-orbit applications. The system is comprised of an electrolyzer which utilizes solar array power to convert water into hydrogen and oxygen reactants, a fuel cell that recombines the reactants back into water and produces power during eclipse, and associated controls and reactant storage. Round-trip electrical efficiencies of RFC systems are typically lower than competing battery energy storage systems. This results in larger solar arrays for the same application, with inherent drag, mass, and cost penalties. However, the increase in solar array size can be limited, if not totally eliminated, because of the ability of RFC systems to use excess solar array power. For this paper, the International Space Station (ISS) application was chosen for evaluation and comparison of battery and RFC energy storage systems. This selection was based on the authors` familiarity with the ISS design and the availability of a detailed in-house computer model specific to the ISS electrical power system (SPACE). Combined altitude and orientation effects, seasonal variations, and beginning-of-life solar array performance were examined for individual orbits at and above specified reference points. Charging characteristics of the battery system were also investigated. The evaluation allowed a comparison of the solar array size required with the existing battery energy storage system to the projected solar array size required with a possible RFC system. The results of the examination indicated that no increase in solar array size would be necessary for the ISS if outfitted with a RFC energy storage system, in spite of the lower round-trip electrical efficiency. For orbits with a minimum of excess power, the battery energy storage system used only 73% of the available solar array power as compared to 100% usage for a RFC system. The usage by the battery system was far less for the orbits

  11. Controlling for peak power extraction from microbial fuel cells can increase stack voltage and avoid cell reversal

    NASA Astrophysics Data System (ADS)

    Boghani, Hitesh C.; Papaharalabos, George; Michie, Iain; Fradler, Katrin R.; Dinsdale, Richard M.; Guwy, Alan J.; Ieropoulos, Ioannis; Greenman, John; Premier, Giuliano C.

    2014-12-01

    Microbial fuel cells (MFCs) are bioelectrochemical systems which can degrade organic materials and are increasingly seen as potential contributors to low carbon technologies, particularly in energy recovery from and treatment of wastewaters. The theoretical maximum open circuit voltage from MFCs lies in the region of 1.1 V, but is reduced substantially by overvoltage losses. Practical use of the power requires stacking or other means to increase voltage. Series stacking of MFCs with typically encountered variability in operating conditions and performance raises the risk of cell reversal, which diminishes overall power performance. A novel strategy of MFC subsystem series connectivity along with maximum power point tracking (MPPT) generates increased power from individual MFCs whilst eliminating cell reversal. MFCs fed with lower concentrations of substrate experienced voltage reversal when connected in normal series connection with one common load, but when MFCs and loads together were connected in series, the underperforming cell is effectively bypassed and maximum power is made available. It is concluded that stack voltage may be increased and cell reversal avoided using the hybrid connectivity along with MPPT. This approach may be suitable for stacked MFC operations in the event that large scale arrays/modules are deployed in treating real wastewaters.

  12. Optimum Operation Condition on Distributed Power Supply System with Micro Gas Turbine/Solid Oxide Fuel Cell

    NASA Astrophysics Data System (ADS)

    Suzuki, Hiroshi; Yamada, Miki; Usui, Hiromoto; Komoda, Yoshiyuki

    In order to find the optimum operation condition of a distributed power supply system of 30kW class micro gas turbine (MGT) and solid oxide fuel cell (SOFC) hybrid system with the combination of line electric power and supplied gas, a system analysis has been performed. In this study, an absorption chiller and a boiler were mounted to utilize the exhausted heat from the MGT/SOFC system. The time variation of energy consumption in 24 hours for house and market models was taken into consideration for the calculation of the energy saving ratio of the present system. The operation ratio defined with the ratio of power supply of MGT/SOFC system to the power required at the peak load was changed as a parameter. From the comparison with the system using line power and gas, it is found that the present system shows high energy saving ratio around 0.4 of the operation ratio, but the energy saving ratio severely decreases in the range of high operation ratio. In this study, it is revealed that the thermal storage system effectively improves the energy saving ratio especially for the house model in winter season.

  13. Cost related sensitivity analysis for optimal operation of a grid-parallel PEM fuel cell power plant

    NASA Astrophysics Data System (ADS)

    El-Sharkh, M. Y.; Tanrioven, M.; Rahman, A.; Alam, M. S.

    Fuel cell power plants (FCPP) as a combined source of heat, power and hydrogen (CHP&H) can be considered as a potential option to supply both thermal and electrical loads. Hydrogen produced from the FCPP can be stored for future use of the FCPP or can be sold for profit. In such a system, tariff rates for purchasing or selling electricity, the fuel cost for the FCPP/thermal load, and hydrogen selling price are the main factors that affect the operational strategy. This paper presents a hybrid evolutionary programming and Hill-Climbing based approach to evaluate the impact of change of the above mentioned cost parameters on the optimal operational strategy of the FCPP. The optimal operational strategy of the FCPP for different tariffs is achieved through the estimation of the following: hourly generated power, the amount of thermal power recovered, power trade with the local grid, and the quantity of hydrogen that can be produced. Results show the importance of optimizing system cost parameters in order to minimize overall operating cost.

  14. The TMI regenerable solid oxide fuel cell

    NASA Technical Reports Server (NTRS)

    Cable, Thomas L.

    1995-01-01

    Energy storage and production in space requires rugged, reliable hardware which minimizes weight, volume, and maintenance while maximizing power output and usable energy storage. These systems generally consist of photovoltaic solar arrays which operate during sunlight cycles to provide system power and regenerate fuel (hydrogen) via water electrolysis; during dark cycles, hydrogen is converted by the fuel cell into system. The currently preferred configuration uses two separate systems (fuel cell and electrolyzer) in conjunction with photovoltaic cells. Fuel cell/electrolyzer system simplicity, reliability, and power-to-weight and power-to-volume ratios could be greatly improved if both power production (fuel cell) and power storage (electrolysis) functions can be integrated into a single unit. The Technology Management, Inc. (TMI), solid oxide fuel cell-based system offers the opportunity to both integrate fuel cell and electrolyzer functions into one unit and potentially simplify system requirements. Based an the TMI solid oxide fuel cell (SOPC) technology, the TMI integrated fuel cell/electrolyzer utilizes innovative gas storage and operational concepts and operates like a rechargeable 'hydrogen-oxygen battery'. Preliminary research has been completed on improved H2/H2O electrode (SOFC anode/electrolyzer cathode) materials for solid oxide, regenerative fuel cells. Improved H2/H2O electrode materials showed improved cell performance in both fuel cell and electrolysis modes in reversible cell tests. ln reversible fuel cell/electrolyzer mode, regenerative fuel cell efficiencies (ratio of power out (fuel cell mode) to power in (electrolyzer model)) improved from 50 percent (using conventional electrode materials) to over 80 percent. The new materials will allow the TMI SOFC system to operate as both the electrolyzer and fuel cell in a single unit. Preliminary system designs have also been developed which indicate the technical feasibility of using the TMI SOFC

  15. LOW-TEMPERATURE, ANODE-SUPPORTED HIGH POWER DENSITY SOLID OXIDE FUEL CELLS WITH NANOSTRUCTURED ELECTRODES

    SciTech Connect

    Anil V. Virkar

    2001-09-26

    Anode-supported solid oxide fuel cells with Ni + yttria-stabilized zirconia (YSZ) anode, YSZ-samaria-doped ceria (SDC) bi-layer electrolyte and Sr-doped LaCoO{sub 3} (LSC) + SDC cathode were fabricated. Fuel used consisted of H{sub 2} diluted with He, N{sub 2}, H{sub 2}O or CO{sub 2}, mixtures of H{sub 2} and CO, and mixtures of CO and CO{sub 2}. Cell performance was measured at 800 C with above-mentioned fuel gas mixtures and air as oxidant. For a given concentration of the diluent, the cell performance was higher with He as the diluent than with N{sub 2} as the diluent. Mass transport through porous Ni-YSZ anode for H{sub 2}-H{sub 2}O, CO-CO{sub 2} binary systems and H{sub 2}-H{sub 2}O-diluent gas ternary systems was analyzed using multicomponent gas diffusion theory. At high concentrations of the diluent, the maximum achievable current density was limited by the anodic concentration polarization. From this measured limiting current density, the corresponding effective gas diffusivity was estimated. Highest effective diffusivity was estimated for fuel gas mixtures containing H{sub 2}-H{sub 2}O-He mixtures ({approx}0.34 cm{sup 2}/s), and the lowest for CO-CO{sub 2} mixtures ({approx}0.07 cm{sup 2}/s). The lowest performance was observed with CO-CO{sub 2} mixture as a fuel, which in part was attributed to the lowest effective diffusivity of the fuels tested.

  16. Fuel cells: A survey

    NASA Technical Reports Server (NTRS)

    Crowe, B. J.

    1973-01-01

    A survey of fuel cell technology and applications is presented. The operating principles, performance capabilities, and limitations of fuel cells are discussed. Diagrams of fuel cell construction and operating characteristics are provided. Photographs of typical installations are included.

  17. Fuel cell-fuel cell hybrid system

    DOEpatents

    Geisbrecht, Rodney A.; Williams, Mark C.

    2003-09-23

    A device for converting chemical energy to electricity is provided, the device comprising a high temperature fuel cell with the ability for partially oxidizing and completely reforming fuel, and a low temperature fuel cell juxtaposed to said high temperature fuel cell so as to utilize remaining reformed fuel from the high temperature fuel cell. Also provided is a method for producing electricity comprising directing fuel to a first fuel cell, completely oxidizing a first portion of the fuel and partially oxidizing a second portion of the fuel, directing the second fuel portion to a second fuel cell, allowing the first fuel cell to utilize the first portion of the fuel to produce electricity; and allowing the second fuel cell to utilize the second portion of the fuel to produce electricity.

  18. Exergy analysis of an integrated solid oxide fuel cell and organic Rankine cycle for cooling, heating and power production

    NASA Astrophysics Data System (ADS)

    Al-Sulaiman, Fahad A.; Dincer, Ibrahim; Hamdullahpur, Feridun

    The study examines a novel system that combined a solid oxide fuel cell (SOFC) and an organic Rankine cycle (ORC) for cooling, heating and power production (trigeneration) through exergy analysis. The system consists of an SOFC, an ORC, a heat exchanger and a single-effect absorption chiller. The system is modeled to produce a net electricity of around 500 kW. The study reveals that there is 3-25% gain on exergy efficiency when trigeneration is used compared with the power cycle only. Also, the study shows that as the current density of the SOFC increases, the exergy efficiencies of power cycle, cooling cogeneration, heating cogeneration and trigeneration decreases. In addition, it was shown that the effect of changing the turbine inlet pressure and ORC pump inlet temperature are insignificant on the exergy efficiencies of the power cycle, cooling cogeneration, heating cogeneration and trigeneration. Also, the study reveals that the significant sources of exergy destruction are the ORC evaporator, air heat exchanger at the SOFC inlet and heating process heat exchanger.

  19. Performance of two different types of anodes in membrane electrode assembly microbial fuel cells for power generation from domestic wastewater

    NASA Astrophysics Data System (ADS)

    Hays, Sarah; Zhang, Fang; Logan, Bruce E.

    2011-10-01

    Graphite fiber brush electrodes provide high surface areas for exoelectrogenic bacteria in microbial fuel cells (MFCs), but the cylindrical brush format limits more compact reactor designs. To enable MFC designs with closer electrode spacing, brush anodes were pressed up against a separator (placed between the electrodes) to reduce the volume occupied by the brush. Higher maximum voltages were produced using domestic wastewater (COD = 390 ± 89 mg L-1) with brush anodes (360 ± 63 mV, 1000 Ω) than woven carbon mesh anodes (200 ± 81 mV) with one or two separators. Maximum power densities were similar for brush anode reactors with one or two separators after 30 days (220 ± 1.2 and 240 ± 22 mW m-2), but with one separator the brush anode MFC power decreased to 130 ± 55 mW m-2 after 114 days. Power densities in MFCs with mesh anodes were very low (<45 mW m-2). Brush anodes MFCs had higher COD removals (80 ± 3%) than carbon mesh MFCs (58 ± 7%), but similar Coulombic efficiencies (8.6 ± 2.9% brush; 7.8 ± 7.1% mesh). These results show that compact (hemispherical) brush anodes can produce higher power and more effective domestic wastewater treatment than flat mesh anodes in MFCs.

  20. Trace heavy metal ions promoted extracellular electron transfer and power generation by Shewanella in microbial fuel cells.

    PubMed

    Xu, Yu-Shang; Zheng, Tao; Yong, Xiao-Yu; Zhai, Dan-Dan; Si, Rong-Wei; Li, Bing; Yu, Yang-Yang; Yong, Yang-Chun

    2016-07-01

    Although microbial fuel cells (MFCs) is considered as one of the most promising technology for renewable energy harvesting, low power output still accounts one of the bottlenecks and limits its further development. In this work, it is found that Cu(2+) (0.1μgL(-1)-0.1mgL(-1)) or Cd(2+) (0.1μgL(-1)-1mgL(-1)) significantly improve the electricity generation in MFCs. The maximum power output achieved with trace level of Cu(2+) (∼6nM) or Cd(2+) (∼5nM) is 1.3 times and 1.6 times higher than that of the control, respectively. Further analysis verifies that addition of Cu(2+) or Cd(2+) effectively improves riboflavin production and bacteria attachment on the electrode, which enhances bacterial extracellular electron transfer (EET) in MFCs. These results unveil the mechanism for power output enhancement by Cu(2+) or Cd(2+) addition, and suggest that metal ion addition should be a promising strategy to enhance EET as well as power generation of MFCs. PMID:27038263

  1. 2007 Fuel Cell Technologies Market Report

    SciTech Connect

    McMurphy, K.

    2009-07-01

    The fuel cell industry, which has experienced continued increases in sales, is an emerging clean energy industry with the potential for significant growth in the stationary, portable, and transportation sectors. Fuel cells produce electricity in a highly efficient electrochemical process from a variety of fuels with low to zero emissions. This report describes data compiled in 2008 on trends in the fuel cell industry for 2007 with some comparison to two previous years. The report begins with a discussion of worldwide trends in units shipped and financing for the fuel cell industry for 2007. It continues by focusing on the North American and U.S. markets. After providing this industry-wide overview, the report identifies trends for each of the major fuel cell applications -- stationary power, portable power, and transportation -- including data on the range of fuel cell technologies -- polymer electrolyte membrane fuel cell (PEMFC), solid oxide fuel cell (SOFC), alkaline fuel cell (AFC), molten carbonate fuel cell (MCFC), phosphoric acid fuel cell (PAFC), and direct-methanol fuel cell (DMFC) -- used for these applications.

  2. The influence of operating temperature on the efficiency of a combined heat and power fuel cell plant

    NASA Astrophysics Data System (ADS)

    Au, S. F.; McPhail, S. J.; Woudstra, N.; Hemmes, K.

    It is generally accepted that the ideal operating temperature of a molten carbonate fuel cell (MCFC) is 650 °C. Nevertheless, when waste heat utilization in the form of an expander and steam production cycle is introduced in the system, another temperature level might prove more productive. This article is a first attempt to the optimization of MCFC operating temperatures of a MCFC system by presenting a case study in which the efficiency of a combined heat and power (CHP) plant is analyzed. The fuel cell plant under investigation is designed around a 250 kW-class MCFC fuelled by natural gas, which is externally reformed by a heat exchange reformer (HER). The operating temperature of the MCFC is varied over a temperature range between 600 and 700 °C while keeping the rest of the system the same as far as possible. Changes in energetic efficiency are given and the causes of these changes are further analyzed. Furthermore, the exergetic efficiencies of the system and the distribution of exergy losses in the system are given. Flowsheet calculations show that there is little dependency on the temperature in the first order. Both the net electrical performance and the overall exergetic performance show a maximum at approximately 675 °C, with an electrical efficiency of 51.9% (LHV), and an exergy efficiency of 58.7%. The overall thermal efficiency of this CHP plant increases from 87.1% at 600 °C to 88.9% at 700 °C. Overall, the change in performance is small in this typical range of MCFC operating temperature.

  3. Fuel cell technology program

    NASA Technical Reports Server (NTRS)

    1971-01-01

    The results of a solid polymer electrolyte fuel cell development program are summarized. A base line design was defined, and materials and components of the base line configuration were fabricated and tested. Concepts representing base line capability extensions in the areas of life, power, specific weight and volume, versatility of operation, field maintenance, and thermal control were identified and evaluated. Liaison and coordination with space shuttle contractors resulted in the exchange of engineering data.

  4. Hydrogen Fuel Cell Automobiles

    NASA Astrophysics Data System (ADS)

    Feldman, Bernard J.

    2005-11-01

    With gasoline now more than 2.00 a gallon, alternate automobile technologies will be discussed with greater interest and developed with more urgency. For our government, the hydrogen fuel cell-powered automobile is at the top of the list of future technologies. This paper presents a simple description of the principles behind this technology and a brief discussion of the pros and cons. It is also an extension on my previous paper on the physics of the automobile engine.

  5. Ultra Efficient CHHP Using a High Temperature Fuel Cell to Provide On-Site Process Reducing Gas, Clean Power, and Heat

    SciTech Connect

    Jahnke, Fred C.

    2015-06-30

    FuelCell Energy and ACuPowder investigated and demonstrated the use of waste anode exhaust gas from a high temperature fuel cell for replacing the reducing gas in a metal processing furnace. Currently companies purchase high pressure or liquefied gases for the reducing gas which requires substantial energy in production, compression/liquefaction, and transportation, all of which is eliminated by on-site use of anode exhaust gas as reducing gas. We performed research on the impact of the gas composition on product quality and then demonstrated at FuelCell Energy’s manufacturing facility in Torrington, Connecticut. This demonstration project continues to operate even though the research program is completed as it provides substantial benefits to the manufacturing facility by supplying power, heat, and hydrogen.

  6. Analysis of environmental factors impacting the life cycle cost analysis of conventional and fuel cell/battery-powered passenger vehicles. Final report

    SciTech Connect

    1995-01-31

    This report presents the results of the further developments and testing of the Life Cycle Cost (LCC) Model previously developed by Engineering Systems Management, Inc. (ESM) on behalf of the U.S. Department of Energy (DOE) under contract No. DE-AC02-91CH10491. The Model incorporates specific analytical relationships and cost/performance data relevant to internal combustion engine (ICE) powered vehicles, battery powered electric vehicles (BPEVs), and fuel cell/battery-powered electric vehicles (FCEVs).

  7. Using single-chamber microbial fuel cells as renewable power sources of electro-Fenton reactors for organic pollutant treatment.

    PubMed

    Zhu, Xiuping; Logan, Bruce E

    2013-05-15

    Electro-Fenton reactions can be very effective for organic pollutant degradation, but they typically require non-sustainable electrical power to produce hydrogen peroxide. Two-chamber microbial fuel cells (MFCs) have been proposed for pollutant treatment using Fenton-based reactions, but these types of MFCs have low power densities and require expensive membranes. Here, more efficient dual reactor systems were developed using a single-chamber MFC as a low-voltage power source to simultaneously accomplish H2O2 generation and Fe(2+) release for the Fenton reaction. In tests using phenol, 75 ± 2% of the total organic carbon (TOC) was removed in the electro-Fenton reactor in one cycle (22 h), and phenol was completely degraded to simple and readily biodegradable organic acids. Compared to previously developed systems based on two-chamber MFCs, the degradation efficiency of organic pollutants was substantially improved. These results demonstrate that this system is an energy-efficient and cost-effective approach for industrial wastewater treatment of certain pollutants. PMID:23523911

  8. Maximum power output and load matching of a phosphoric acid fuel cell-thermoelectric generator hybrid system

    NASA Astrophysics Data System (ADS)

    Chen, Xiaohang; Wang, Yuan; Cai, Ling; Zhou, Yinghui

    2015-10-01

    Based on the current models of phosphoric acid fuel cells (PAFCs) and thermoelectric generators (TGs), a new hybrid system is proposed, in which the effects of multi-irreversibilities resulting from the activation, concentration, and ohmic overpotentials in the PAFC, Joule heat and heat leak in the TG, finite-rate heat transfer between the TG and the heat reservoirs, and heat leak from the PAFC to the environment are taken into account. Expressions for the power output and efficiency of the PAFC, TG, and hybrid system are analytically derived and directly used to discuss the performance characteristics of the hybrid system. The optimal relationship between the electric currents in the PAFC and TG is obtained. The maximum power output is numerically calculated. It is found that the maximum power output density of the hybrid system will increase about 150 Wm-2, compared with that of a single PAFC. The problem how to optimally match the load resistances of two subsystems is discussed. Some significant results for practical hybrid systems are obtained.

  9. Large size biogas-fed Solid Oxide Fuel Cell power plants with carbon dioxide management: Technical and economic optimization

    NASA Astrophysics Data System (ADS)

    Curletti, F.; Gandiglio, M.; Lanzini, A.; Santarelli, M.; Maréchal, F.

    2015-10-01

    This article investigates the techno-economic performance of large integrated biogas Solid Oxide Fuel Cell (SOFC) power plants. Both atmospheric and pressurized operation is analysed with CO2 vented or captured. The SOFC module produces a constant electrical power of 1 MWe. Sensitivity analysis and multi-objective optimization are the mathematical tools used to investigate the effects of Fuel Utilization (FU), SOFC operating temperature and pressure on the plant energy and economic performances. FU is the design variable that most affects the plant performance. Pressurized SOFC with hybridization with a gas turbine provides a notable boost in electrical efficiency. For most of the proposed plant configurations, the electrical efficiency ranges in the interval 50-62% (LHV biogas) when a trade-off of between energy and economic performances is applied based on Pareto charts obtained from multi-objective plant optimization. The hybrid SOFC is potentially able to reach an efficiency above 70% when FU is 90%. Carbon capture entails a penalty of more 10 percentage points in pressurized configurations mainly due to the extra energy burdens of captured CO2 pressurization and oxygen production and for the separate and different handling of the anode and cathode exhausts and power recovery from them.

  10. A 3D paper-based enzymatic fuel cell for self-powered, low-cost glucose monitoring.

    PubMed

    Fischer, Christopher; Fraiwan, Arwa; Choi, Seokheun

    2016-05-15

    In this work, we demonstrate a novel low-cost, self-powered paper-based biosensor for glucose monitoring. The device operating mechanism is based on a glucose/oxygen enzymatic fuel cell using an electrochemical energy conversion as a transducing element for glucose monitoring. The self-powered glucose biosensor features (i) a 3D origami paper-based structure for easy system integration onto paper, (ii) an air-cathode on paper for low-cost production and easy operation, and (iii) a screen printed chitosan/glucose oxidase anode for stable current generation as an analytical signal for glucose monitoring. The sensor showed a linear range of output current at 1-5mM glucose (R(2)=0.996) with a sensitivity of 0.02 µA mM(-1). The advantages offered by such a device, including a low cost, lack of external power sources/sophisticated external transducers, and the capacity to rapidly generate reliable results, are well suited for the clinical and social settings of the developing world. PMID:26706941

  11. Influence of pressurized anode chamber on ion transports and power generation of UF membrane microbial fuel cells (UF-MFCs)

    NASA Astrophysics Data System (ADS)

    Kim, Kyoung-Yeol; Chae, Kyu-Jung; Yang, Euntae; Lee, Mi-Young; Kim, In S.

    2015-04-01

    Ultrafiltration membrane integrated microbial fuel cell (UF-MFC) has developed to produce high-quality effluents by integrating the membrane filtration process into the MFC system. During UF-MFC operation, however, unexpected power reductions were observed under different pressures that were applied in the anode chamber (22.0% and 25.5% at 0.7 bar and 2.1 bar, respectively). It was hypothesized that those of power reductions might occur due to the limitation of ion transport across the UF membrane- which could be caused by the pressurized anode chamber to filter the anode solution through the UF membrane. A test with a NaCl concentrated cathode solution showed few dissolved ions being transported from the cathode to anode chamber while the pressure was being applied in the anode chamber. This result clearly indicates that the limitation of ion transport from the cathode to the pressurized anode chamber is a significant factor affecting the power density of UF-MFCs, even more so than water permeation through the UF membrane.

  12. Reducing start-up time and minimizing energy losses of Microbial Fuel Cells using Maximum Power Point Tracking strategy

    NASA Astrophysics Data System (ADS)

    Molognoni, Daniele; Puig, Sebastià; Balaguer, M. Dolors; Liberale, Alessandro; Capodaglio, Andrea G.; Callegari, Arianna; Colprim, Jesús

    2014-12-01

    Microbial Fuel Cells (MFCs) are considered to be an environmental friendly energy conversion technology. The main limitations that delay their industrialization include low current and power densities achievable and long start-up times. Maximum Power Point Tracking (MPPT) has been proposed as a method to enhance MFCs electrical performances. However, the specialized literature is still lacking of experimental works on scaled-up reactors and/or real wastewater utilization. This study evaluates the impact of a MPPT system applied to MFCs treating swine wastewater in terms of start-up time and long-term performance. For this purpose, two replicate cells were compared, one with applied MPPT control and one working with fixed resistance. Both MFCs were continuously fed with swine wastewater to validate the control system under real and dynamic conditions. The study demonstrated that the automatic resistance control was able to reduce the start-up time of about one month. Moreover, MPPT system increased of 40% the Coulombic efficiency at steady-state conditions, reduced energy losses associated with anode and cathode reactions and limited methanogenic activity in the anode chamber. A power density of 5.0 ± 0.2 W m-3 NAC was achieved feeding the system at an organic loading rate of 10 kg COD m-3 d-1.

  13. Carbonization and activation of inexpensive semicoke-packed electrodes to enhance power generation of microbial fuel cells.

    PubMed

    Wei, Jincheng; Liang, Peng; Zuo, Kuichang; Cao, Xiaoxin; Huang, Xia

    2012-06-01

    A simple and low-cost modification method was developed to improve the power generation performance of inexpensive semicoke electrode in microbial fuel cells (MFCs). After carbonization and activation with water vapor at 800-850 °C, the MFC with the activated coke (modified semicoke) anode produced a maximum power density of 74 Wm(-3) , 17 Wm(-3) , and 681 mWm(-2) (normalized to anodic liquid volume, total reactor volume, and projected membrane surface area, respectively), which was 124 % higher than MFCs using a semicoke anode (33 Wm(-3) , 8 Wm(-3) , and 304 mWm(-2) ). When they were used as biocathode materials, activated coke produced a maximum power density of 177 Wm(-3) , 41 Wm(-3) , and 1628 mWm(-2) (normalized to cathodic liquid volume, total reactor volume, and projected membrane surface area, respectively), which was 211 % higher than that achieved by MFCs using a semicoke cathode (57 Wm(-3) , 13 Wm(-3) , and 524 mWm(-2) ). A substantial increase was also noted in the conductivity, C/O mass ratio, and specific area for activated coke, which reduced the ohmic resistance, increased biomass density, and promoted electron transfer between bacteria and electrode surface. The activated coke anode also produced a higher Coulombic efficiency and chemical oxygen demand removal rate than the semicoke anode. PMID:22639403

  14. Sustainable energy recovery in wastewater treatment by microbial fuel cells: stable power generation with nitrogen-doped graphene cathode.

    PubMed

    Liu, Yuan; Liu, Hong; Wang, Chuan; Hou, Shuang-Xia; Yang, Nuan

    2013-12-01

    Microbial fuel cells (MFCs) recover energy sustainably in wastewater treatment. Performance of non-noble cathode catalysts with low cost in neutral medium is vital for stable power generation. Nitrogen-doped graphene (NG) as cathode catalyst was observed to exhibit high and durable activity at buffered pH 7.0 during electrochemical measurements and in MFCs with respect to Pt/C counterpart. Electrochemical measurements showed that the oxygen reduction reaction (ORR) on NG possessed sustained activity close to the state-of-art Pt/C in terms of onset potential and electron transfer number. NG-MFCs displayed maximum voltage output of 650 mV and maximum power density of 776 ± 12 mW m(-2), larger than 610 mV and 750 ± 19 mW m(-2) of Pt/C-MFCs, respectively. Furthermore, long-time test lasted over 90 days, during which the maximum power density of NG-MFCs declined by 7.6%, with stability comparable to Pt/C-MFCs. Structure characterization of NG implied that the relatively concentrated acidic oxygen-containing groups improved such long-time stability by repelling the protons due to the same electrostatic force, and thus the C-N active centers for ORR were left undestroyed. These findings demonstrated the competitive advantage of NG to advance the application of MFCs for recovering biomass energy in treatment of wastewater with neutral pH. PMID:24219223

  15. Operational, design and microbial aspects related to power production with microbial fuel cells implemented in constructed wetlands.

    PubMed

    Corbella, Clara; Guivernau, Miriam; Viñas, Marc; Puigagut, Jaume

    2015-11-01

    This work aimed at determining the amount of energy that can be harvested by implementing microbial fuel cells (MFC) in horizontal subsurface constructed wetlands (HSSF CWs) during the treatment of real domestic wastewater. To this aim, MFC were implemented in a pilot plant based on two HSSF CW, one fed with primary settled wastewater (Settler line) and the other fed with the effluent of a hydrolytic up-flow sludge blanket reactor (HUSB line). The eubacterial and archaeal community was profiled on wetland gravel, MFC electrodes and primary treated wastewater by means of 16S rRNA gene-based 454-pyrosequencing and qPCR of 16S rRNA and mcrA genes. Maximum current (219 mA/m(2)) and power (36 mW/m(2)) densities were obtained for the HUSB line. Power production pattern correlated well with water level fluctuations within the wetlands, whereas the type of primary treatment implemented had a significant impact on the diversity and relative abundance of eubacteria communities colonizing MFC. It is worth noticing the high predominance (13-16% of relative abundance) of one OTU belonging to Geobacter on active MFC of the HUSB line that was absent for the settler line MFC. Hence, MFC show promise for power production in constructed wetlands receiving the effluent of a HUSB reactor. PMID:26253894

  16. A techno-economic comparison of fuel processors utilizing diesel for solid oxide fuel cell auxiliary power units

    NASA Astrophysics Data System (ADS)

    Nehter, Pedro; Hansen, John Bøgild; Larsen, Peter Koch

    Ultra-low sulphur diesel (ULSD) is the preferred fuel for mobile auxiliary power units (APU). The commercial available technologies in the kW-range are combustion engine based gensets, achieving system efficiencies about 20%. Solid oxide fuel cells (SOFC) promise improvements with respect to efficiency and emission, particularly for the low power range. Fuel processing methods i.e., catalytic partial oxidation, autothermal reforming and steam reforming have been demonstrated to operate on diesel with various sulphur contents. The choice of fuel processing method strongly affects the SOFC's system efficiency and power density. This paper investigates the impact of fuel processing methods on the economical potential in SOFC APUs, taking variable and capital cost into account. Autonomous concepts without any external water supply are compared with anode recycle configurations. The cost of electricity is very sensitive on the choice of the O/C ratio and the temperature conditions of the fuel processor. A sensitivity analysis is applied to identify the most cost effective concept for different economic boundary conditions. The favourite concepts are discussed with respect to technical challenges and requirements operating in the presence of sulphur.

  17. Fuel-Cell Water Separator

    NASA Technical Reports Server (NTRS)

    Burke, Kenneth Alan; Fisher, Caleb; Newman, Paul

    2010-01-01

    The main product of a typical fuel cell is water, and many fuel-cell configurations use the flow of excess gases (i.e., gases not consumed by the reaction) to drive the resultant water out of the cell. This two-phase mixture then exits through an exhaust port where the two fluids must again be separated to prevent the fuel cell from flooding and to facilitate the reutilization of both fluids. The Glenn Research Center (GRC) has designed, built, and tested an innovative fuel-cell water separator that not only removes liquid water from a fuel cell s exhaust ports, but does so with no moving parts or other power-consuming components. Instead it employs the potential and kinetic energies already present in the moving exhaust flow. In addition, the geometry of the separator is explicitly intended to be integrated into a fuel-cell stack, providing a direct mate with the fuel cell s existing flow ports. The separator is also fully scalable, allowing it to accommodate a wide range of water removal requirements. Multiple separators can simply be "stacked" in series or parallel to adapt to the water production/removal rate. GRC s separator accomplishes the task of water removal by coupling a high aspect- ratio flow chamber with a highly hydrophilic, polyethersulfone membrane. The hydrophilic membrane readily absorbs and transports the liquid water away from the mixture while simultaneously resisting gas penetration. The expansive flow path maximizes the interaction of the water particles with the membrane while minimizing the overall gas flow restriction. In essence, each fluid takes its corresponding path of least resistance, and the two fluids are effectively separated. The GRC fuel-cell water separator has a broad range of applications, including commercial hydrogen-air fuel cells currently being considered for power generation in automobiles.

  18. Navy fuel cell demonstration project.

    SciTech Connect

    Black, Billy D.; Akhil, Abbas Ali

    2008-08-01

    This is the final report on a field evaluation by the Department of the Navy of twenty 5-kW PEM fuel cells carried out during 2004 and 2005 at five Navy sites located in New York, California, and Hawaii. The key objective of the effort was to obtain an engineering assessment of their military applications. Particular issues of interest were fuel cell cost, performance, reliability, and the readiness of commercial fuel cells for use as a standalone (grid-independent) power option. Two corollary objectives of the demonstration were to promote technological advances and to improve fuel performance and reliability. From a cost perspective, the capital cost of PEM fuel cells at this stage of their development is high compared to other power generation technologies. Sandia National Laboratories technical recommendation to the Navy is to remain involved in evaluating successive generations of this technology, particularly in locations with greater environmental extremes, and it encourages their increased use by the Navy.

  19. Fuel Cells for Space Science Applications

    NASA Technical Reports Server (NTRS)

    Burke, Kenneth A.

    2003-01-01

    Fuel cell technology has been receiving more attention recently as a possible alternative to the internal combustion engine for our automobile. Improvements in fuel cell designs as well as improvements in lightweight high-pressure gas storage tank technology make fuel cell technology worth a look to see if fuel cells can play a more expanded role in space missions. This study looks at the specific weight density and specific volume density of potential fuel cell systems as an alternative to primary and secondary batteries that have traditionally been used for space missions. This preliminary study indicates that fuel cell systems have the potential for energy densities of greater than 500 W-hr/kg, greater than 500W/kg and greater than 400 W-hr/liter, greater than 200 W/liter. This level of performance makes fuel cells attractive as high-power density, high-energy density sources for space science probes, planetary rovers and other payloads. The power requirements for these space missions are, in general, much lower than the power levels where fuel cells have been used in the past. Adaptation of fuel cells for space science missions will require down-sizing the fuel cell stack and making the fuel cell operate without significant amounts of ancillary equipment.

  20. Status of the US Fuel Cell Program

    SciTech Connect

    Williams, M.C.

    1996-04-01

    The U.S. Department of Energy (DOE) is sponsoring major programs to develop high efficiency fuel cell technologies to produce electric power from natural gas and other hydrogen sources. Fuel cell systems offer attractive potential for future electric power generation and are expected to have worldwide markets. They offer ultra-high energy conversion efficiency and extremely low environmental emissions. As modular units for distributed power generation, fuel cells are expected to be particularly beneficial where their by-product, heat, can be effectively used in cogeneration applications. Advanced fuel cell power systems fueled with natural gas are expected to be commercially available after the turn of the century.

  1. Bioanodes/biocathodes formed at optimal potentials enhance subsequent pentachlorophenol degradation and power generation from microbial fuel cells.

    PubMed

    Huang, Liping; Wang, Qiang; Quan, Xie; Liu, Yaxuan; Chen, Guohua

    2013-12-01

    Bioanodes formed at an optimal potential of 200 mV vs. SHE and biocathodes developed at -300 mV vs. SHE in bioelectrochemical cells (BECs) enhanced the subsequent performances of microbial fuel cells (MFCs) compared to the un-treated controls. While the startup times were reduced to 320 h (bioanodes) and 420-440 h (biocathodes), PCP degradation rates were improved by 28.5% (bioanodes) and 21.5% (biocathodes), and power production by 41.7% (bioanodes) and 44% (biocathodes). Accordingly, there were less accumulated products of PCP de-chlorination in the biocathodes whereas PCP in the bioanodes was more efficiently de-chlorinated, resulting in the formation of a new product of 3,4,5-trichlorophenol (24.3 ± 2.2 μM at 96 h). Charges were diverted to more generation of electricity in the bioanodes at 200 mV while oxygen in the biocathodes at -300 mV acted as a primary electron acceptor. Dominant bacteria known as recalcitrant organic degraders and/or exoelectrogens/electrotrophs included Desulfovibrio carbinoliphilus and Dechlorospirillum sp. on the bioanodes at 200 mV, and Desulfovibrio marrakechensis, Comamonas testosteroni and Comamonas sp. on the biocathodes at -300 mV. These results demonstrated that an optimal potential was a feasible approach for developing both bioanodes and biocathodes for efficient PCP degradation and power generation from MFCs. PMID:23747520

  2. Assembly of coupled redox fuel cells using copper as electron acceptors to generate power and its in-situ retrieval

    NASA Astrophysics Data System (ADS)

    Zhang, Hui-Min; Xu, Wei; Li, Gang; Liu, Zhan-Meng; Wu, Zu-Cheng; Li, Bo-Geng

    2016-02-01

    Energy extraction from waste has attracted much interest nowadays. Herein, a coupled redox fuel cell (CRFC) device using heavy metals, such as copper, as an electron acceptor is assembled to testify the recoveries of both electricity and the precious metal without energy consumption. In this study, a NaBH4-Cu(II) CRFC was employed as an example to retrieve copper from a dilute solution with self-electricity production. The properties of the CRFC have been characterized, and the open circuit voltage was 1.65 V with a maximum power density of 7.2 W m-2 at an initial Cu2+ concentration of 1,600 mg L-1 in the catholyte. 99.9% of the 400 mg L-1 copper was harvested after operation for 24 h, and the product formed on the cathode was identified as elemental copper. The CRFC demonstrated that useful chemicals were recovered and the electricity contained in the chemicals was produced in a self-powered retrieval process.

  3. Power generation using spinel manganese-cobalt oxide as a cathode catalyst for microbial fuel cell applications.

    PubMed

    Mahmoud, Mohamed; Gad-Allah, Tarek A; El-Khatib, K M; El-Gohary, Fatma

    2011-11-01

    This study focused on the use of spinel manganese-cobalt (Mn-Co) oxide, prepared by a solid state reaction, as a cathode catalyst to replace platinum in microbial fuel cells (MFCs) applications. Spinel Mn-Co oxides, with an Mn/Co atomic ratios of 0.5, 1, and 2, were prepared and examined in an air cathode MFCs which was fed with a molasses-laden synthetic wastewater and operated in batch mode. Among the three Mn-Co oxide cathodes and after 300 h of operation, the Mn-Co oxide catalyst with Mn/Co atomic ratio of 2 (MnCo-2) exhibited the highest power generation 113 mW/m2 at cell potential of 279 mV, which were lower than those for the Pt catalyst (148 mW/m2 and 325 mV, respectively). This study indicated that using spinel Mn-Co oxide to replace platinum as a cathodic catalyst enhances power generation, increases contaminant removal, and substantially reduces the cost of MFCs. PMID:21944282

  4. Evaluation of gasification and gas-cleanup processes for use in molten-carbonate fuel-cell power plants

    SciTech Connect

    Vidt, E.J.; Jablonski, G.; Alvin, M.A.; Wenglarz, R.A.; Patel, P.

    1981-12-01

    This interim report satisfies the Task B requirement to define process configurations for systems suitable for supplying fuel to molten carbonate fuel cells (MCFC) in industrial and utility power plants. The configurations studied include entrained, fluidized-bed, gravitating-bed, and molten salt gasifiers, both air and oxygen blown. Desulfurization systems utilizing wet scrubbing processes, such as Selexol and Rectisol II, and dry sorbents, such as iron oxide and dolomite, were chosen for evaluation. Cleanup systems not chosen by DOE's MCFC contractors, General Electric and United Technologies, Inc., for their MCFC power plant work by virtue of the resource requirements of those systems for commercial development were chosen for detailed study in Tasks C and D of this contract. Such systems include Westinghouse fluidized-bed gasification, air and oxygen blown, Rockwell molten carbonate air-blown gasification, METC iron oxide desulfurization, and dolomitic desulfurization. In addition, for comparison, gasification systems such as the Texaco entrained and the British Gas/Lurgi slagging units, along with wet scrubbing by Rectisol II, have also been chosen for detailed study.

  5. Assembly of coupled redox fuel cells using copper as electron acceptors to generate power and its in-situ retrieval

    PubMed Central

    Zhang, Hui-Min; Xu, Wei; Li, Gang; Liu, Zhan-Meng; Wu, Zu-Cheng; Li, Bo-Geng

    2016-01-01

    Energy extraction from waste has attracted much interest nowadays. Herein, a coupled redox fuel cell (CRFC) device using heavy metals, such as copper, as an electron acceptor is assembled to testify the recoveries of both electricity and the precious metal without energy consumption. In this study, a NaBH4-Cu(II) CRFC was employed as an example to retrieve copper from a dilute solution with self-electricity production. The properties of the CRFC have been characterized, and the open circuit voltage was 1.65 V with a maximum power density of 7.2 W m−2 at an initial Cu2+ concentration of 1,600 mg L−1 in the catholyte. 99.9% of the 400 mg L−1 copper was harvested after operation for 24 h, and the product formed on the cathode was identified as elemental copper. The CRFC demonstrated that useful chemicals were recovered and the electricity contained in the chemicals was produced in a self-powered retrieval process. PMID:26877144

  6. Development of molten carbonate fuel cell power plant technology. Quarterly technical progress report No. 2, January 1-March 31, 1980

    SciTech Connect

    Healy, H. C.; Sanderson, R. A.; Wertheim, F. J.; Farris, P. F.; Mientek, A. P.; Maricle, D. L.; Briggs, T. A.; Preston, Jr., J. L.; Louis, G. A.; Abrams, M. L.; Bushnell, C. L.; Nickols, R. C.; Gelting, R. L.; Katz, M.; Stewart, R. C.; Kunz, H. R.; Gruver, G. A.; Bregoli, L. J.; Steuernagel, W. H.; Smith, R.; Smith, S. W.; Szymanski, S. T.

    1980-08-01

    The overall objective of this 29-month program is to develop and verify the design of a prototype molten carbonate fuel cell stack which meets the requirements of 1990's competitive coal-fired electrical utility central station or industrial cogeneration power plants. During this quarter, effort was continued in all four major task areas: Task 1 - system studies to define the reference power plant design; Task 2 - cell and stack design, development and verification; Task 3 - preparation for fabrication and testing of the full-scale prototype stack; and Task 4 - developing the capability for operation of stacks on coal-derived gas. In the system study activity of Task 1, preliminary module and cell stack design requirements were completed. Fuel processor characterization has been completed by Bechtel National, Inc. Work under Task 2 defined design approaches for full-scale stack busbars and electrical isolation of reactant manifolds and reactant piping. Preliminary design requirements were completed for the anode. Conductive nickel oxide for cathode fabrication has been made by oxidation and lithiation of porous nickel sheet stock. A method of mechanizing the tape casting process for increased production rates was successfully demonstrated under Task 3. In Task 4, theoretical calculations indicated that hydrogen cyanide and ammonia, when present as impurities in the stack fuel gas, will have no harmful effects. Laboratory experiments using higher than anticipated levels of ethylene showed no harmful effects. Components for the mobile test facility are being ordered.

  7. Electrical start-up for diesel fuel processing in a fuel-cell-based auxiliary power unit

    NASA Astrophysics Data System (ADS)

    Samsun, Remzi Can; Krupp, Carsten; Tschauder, Andreas; Peters, Ralf; Stolten, Detlef

    2016-01-01

    As auxiliary power units in trucks and aircraft, fuel cell systems with a diesel and kerosene reforming capacity offer the dual benefit of reduced emissions and fuel consumption. In order to be commercially viable, these systems require a quick start-up time with low energy input. In pursuit of this end, this paper reports an electrical start-up strategy for diesel fuel processing. A transient computational fluid dynamics model is developed to optimize the start-up procedure of the fuel processor in the 28 kWth power class. The temperature trend observed in the experiments is reproducible to a high degree of accuracy using a dual-cell approach in ANSYS Fluent. Starting from a basic strategy, different options are considered for accelerating system start-up. The start-up time is reduced from 22 min in the basic case to 9.5 min, at an energy consumption of 0.4 kW h. Furthermore, an electrical wire is installed in the reformer to test the steam generation during start-up. The experimental results reveal that the generation of steam at 450 °C is possible within seconds after water addition to the reformer. As a result, the fuel processor can be started in autothermal reformer mode using the electrical concept developed in this work.

  8. Assembly of coupled redox fuel cells using copper as electron acceptors to generate power and its in-situ retrieval.

    PubMed

    Zhang, Hui-Min; Xu, Wei; Li, Gang; Liu, Zhan-Meng; Wu, Zu-Cheng; Li, Bo-Geng

    2016-01-01

    Energy extraction from waste has attracted much interest nowadays. Herein, a coupled redox fuel cell (CRFC) device using heavy metals, such as copper, as an electron acceptor is assembled to testify the recoveries of both electricity and the precious metal without energy consumption. In this study, a NaBH4-Cu(II) CRFC was employed as an example to retrieve copper from a dilute solution with self-electricity production. The properties of the CRFC have been characterized, and the open circuit voltage was 1.65 V with a maximum power density of 7.2 W m(-2) at an initial Cu(2+) concentration of 1,600 mg L(-1) in the catholyte. 99.9% of the 400 mg L(-1) copper was harvested after operation for 24 h, and the product formed on the cathode was identified as elemental copper. The CRFC demonstrated that useful chemicals were recovered and the electricity contained in the chemicals was produced in a self-powered retrieval process. PMID:26877144

  9. Enhancing the power generation in microbial fuel cells with effective utilization of goethite recovered from mining mud as anodic catalyst.

    PubMed

    Jadhav, Dipak A; Ghadge, Anil N; Ghangrekar, Makarand M

    2015-09-01

    Catalytic effect of goethite recovered from iron-ore mining mud was studied in microbial fuel cells (MFCs). Characterization of material recovered from mining mud confirms the recovery of iron oxide as goethite. Heat treated goethite (550 °C) and untreated raw goethite were coated on stainless-steel anode of MFC-1 and MFC-2, respectively; whereas, unmodified stainless-steel anode was used in MFC-3 (control). Fivefold increment in power was obtained in MFC-1 (17.1 W/m(3) at 20 Ω) than MFC-3 (3.5 W/m(3)). MFC with raw goethite coated anode also showed enhanced power (11 W/m(3)). Higher Coulombic efficiency (34%) was achieved in MFC-1 than control MFC-3 (13%). Decrease in mass-transport losses and higher redox current during electrochemical analyses support improved electron transfer with the use of goethite on anode. Cheaper goethite coating kinetically accelerates the electron transfer between bacteria and anode, proving to be a novel approach for enhancing the electricity generation along with organic matter removal in MFC. PMID:25983229

  10. Assessment of the Current Level of Automation in the Manufacture of Fuel Cell Systems for Combined Heat and Power Applications

    SciTech Connect

    Ulsh, M.; Wheeler, D.; Protopappas, P.

    2011-08-01

    The U.S. Department of Energy (DOE) is interested in supporting manufacturing research and development (R&D) for fuel cell systems in the 10-1,000 kilowatt (kW) power range relevant to stationary and distributed combined heat and power applications, with the intent to reduce manufacturing costs and increase production throughput. To assist in future decision-making, DOE requested that the National Renewable Energy Laboratory (NREL) provide a baseline understanding of the current levels of adoption of automation in manufacturing processes and flow, as well as of continuous processes. NREL identified and visited or interviewed key manufacturers, universities, and laboratories relevant to the study using a standard questionnaire. The questionnaire covered the current level of vertical integration, the importance of quality control developments for automation, the current level of automation and source of automation design, critical balance of plant issues, potential for continuous cell manufacturing, key manufacturing steps or processes that would benefit from DOE support for manufacturing R&D, the potential for cell or stack design changes to support automation, and the relationship between production volume and decisions on automation.

  11. Power densities and microbial communities of brewery wastewater-fed microbial fuel cells according to the initial substrates.

    PubMed

    Yu, Jaecheul; Park, Younghyun; Kim, Byunggoon; Lee, Taeho

    2015-01-01

    Single-chamber microbial fuel cells (MFCs) acclimated with glucose, butyrate, propionate, acetate, and a mixture of the four were operated with brewery wastewater (BWW) under a fed-batch mode. Glucose-fed MFC (GW-MFC) showed the highest maximum power density (PDmax) of 1,519 mW/m(2), followed in order by acetate-fed MFC (AW-MFC), mixed substrates-fed MFC (MW-MFC), butyrate-fed MFC (BW-MFC), and propionate-fed MFC (PW-MFC). After changing to BWW, power production was decreased for all MFCs. MFC acclimated with glucose showed the highest PDmax of 890 ± 12 mW/m(2), followed in order by MW-MFC, AW-MFC, BW-MFC, and PW-MFC. The PDmax in BWW-MFC, which was acclimated and operated with BWW, of 552 mW/m(2) was less than that of GW-MFC and MW-MFC but more than that of AW-MFC, BW-MFC, and PW-MFC. MFCs with fermentable substrates were less affected by the BWW. Gammaproteobacteria, including Pseudomonas sp., Acinetobacter sp. and Xanthomonas axonopodis, were found in all MFCs with pure substrates and Rubrivivax benzoatilyticus, thiobacillus sp. and Denitratisoma oestradiolicum belonging to Betaproteobacteria were newly detected in all MFCs when the substrate was changed to BWW. PMID:24973903

  12. Conceptual design and selection of a biodiesel fuel processor for a vehicle fuel cell auxiliary power unit

    NASA Astrophysics Data System (ADS)

    Specchia, S.; Tillemans, F. W. A.; van den Oosterkamp, P. F.; Saracco, G.

    Within the European project BIOFEAT (biodiesel fuel processor for a fuel cell auxiliary power unit for a vehicle), a complete modular 10 kW e biodiesel fuel processor capable of feeding a PEMFC will be developed, built and tested to generate electricity for a vehicle auxiliary power unit (APU). Tail pipe emissions reduction, increased use of renewable fuels, increase of hydrogen-fuel economy and efficient supply of present and future APU for road vehicles are the main project goals. Biodiesel is the chosen feedstock because it is a completely natural and thus renewable fuel. Three fuel processing options were taken into account at a conceptual design level and compared for hydrogen production: (i) autothermal reformer (ATR) with high and low temperature shift (HTS/LTS) reactors; (ii) autothermal reformer (ATR) with a single medium temperature shift (MTS) reactor; (iii) thermal cracker (TC) with high and low temperature shift (HTS/LTS) reactors. Based on a number of simulations (with the AspenPlus® software), the best operating conditions were determined (steam-to-carbon and O 2/C ratios, operating temperatures and pressures) for each process alternative. The selection of the preferential fuel processing option was consequently carried out, based on a number of criteria (efficiency, complexity, compactness, safety, controllability, emissions, etc.); the ATR with both HTS and LTS reactors shows the most promising results, with a net electrical efficiency of 29% (LHV).

  13. Dynamic evaluation of low-temperature metal-supported solid oxide fuel cell oriented to auxiliary power units

    NASA Astrophysics Data System (ADS)

    Wang, Zhenwei; Berghaus, Jörg Oberste; Yick, Sing; Decès-Petit, Cyrille; Qu, Wei; Hui, Rob; Maric, Radenka; Ghosh, Dave

    A metal-supported solid oxide fuel cell (SOFC) composed of a Ni-Ce 0.8Sm 0.2O 2- δ (Ni-SDC) cermet anode and an SDC electrolyte was fabricated by suspension plasma spraying on a Hastelloy X substrate. The cathode, an Sm 0.5Sr 0.5CoO 3 (SSCo)-SDC composite, was screen-printed and fired in situ. The dynamic behaviour of the cell was measured while subjected to complete fuel shutoff and rapid start-up cycles, as typically encountered in auxiliary power units (APU) applications. A promising performance - with a maximum power density (MPD) of 0.176 W cm -2 at 600 °C - was achieved using humidified hydrogen as fuel and air as the oxidant. The cell also showed excellent resistance to oxidation at 600 °C during fuel shutoff, with only a slight drop in performance after reintroduction of the fuel. The Cr and Mn species in the Hastelloy X alloy appeared to be preferentially oxidized while the oxidation of nickel in the metallic substrate was temporarily alleviated. In rapid start-up cycles with a heating rate of 60 °C min -1, noticeable performance deterioration took place in the first two thermal cycles, and then continued at a much slower rate in subsequent cycles. A postmortem analysis of the cell suggested that the degradation was mainly due to the mismatch of the thermal expansion coefficient across the cathode/electrolyte interface.

  14. Renewable Electricity Generation via Solar-Powered Methanol Reforming: Hybrid Proton Exchange Membrane Fuel Cell Systems Based on Novel Non-Concentrating, Intermediate-Temperature Solar Collectors

    NASA Astrophysics Data System (ADS)

    Real, Daniel J.

    Tremendous research efforts have been conducted studying the capturing and conversion of solar energy. Solar thermal power systems offer a compelling opportunity for renewable energy utilization with high efficiencies and excellent cost-effectiveness. The goal of this work was to design a non-concentrating collector capable of reaching temperatures above 250 °C, use this collector to power methanol steam reforming, and operate a proton exchange membrane (PEM) fuel cell using the generated hydrogen. The study presents the construction and characterization of a non-concentrating, intermediate-temperature, fin-in-tube evacuated solar collector, made of copper and capable of reaching stagnation temperatures of 268.5 °C at 1000 W/m2 irradiance. The collector was used to power methanol steam reforming, including the initial heating and vaporization of liquid reactants and the final heating of the gaseous reactants. A preferential oxidation (PROX) catalyst was used to remove CO from simulated reformate gas, and this product gas was used to operate a PEM fuel cell. The results show 1) that the outlet temperature is not limited by heat transfer from the absorber coating to the heat transfer fluid, but by the amount of solar energy absorbed. This implicates a constant heat flux description of the heat transfer process and allows for the usage of materials with lower thermal conductivity than copper. 2) It is possible to operate a PEM fuel cell from reformate gas if a PROX catalyst is used to remove CO from the gas. 3) The performance of the fuel cell is only slightly decreased (~4%) by CO2 dilution present in the reformate and PROX gas. These results provide a foundation for the first renewable electricity generation via solar-powered methanol reforming through a hybrid PEM fuel cell system based on novel non-concentrating, intermediate-temperature solar collectors.

  15. Sacrificing power for more cost-effective treatment: A techno-economic approach for engineering microbial fuel cells.

    PubMed

    Stoll, Zachary A; Ma, Zhaokun; Trivedi, Christopher B; Spear, John R; Xu, Pei

    2016-10-01

    Microbial fuel cells (MFCs) are a promising energy-positive wastewater treatment technology, however, the system's cost-effectiveness has been overlooked. In this study, two new anode materials - hard felt (HF) and carbon foam (CF) - were evaluated against the standard graphite brush (GB) to determine if using inexpensive materials with less than ideal properties can achieve more cost-effective treatment than high-cost, high-performing materials. Using domestic wastewater as the substrate, power densities for the GB, HF and CF-MFCs were 393, 339 and 291 mW m(-2) normalized by cathodic surface area, respectively. Higher power densities correlated with larger anodic surface areas and anodic current densities but not with electrical conductivity. Cyclic voltammetry revealed that redox systems used for extracellular electron transport in the GB, HF and CF-MFCs were similar (-0.143 ± 0.046, -0.158 ± 0.004 and -0.100 ± 0.014 V vs. Ag/AgCl) and that the electrochemical kinetics of the MFCs showed no correlation with their respective electrical conductivity. 16S rRNA sequencing showed the GB, HF and CF microbial community compositions were not statistically different while organic removal rates were nearly identical for all MFCs. The HF-MFC generated a power output to electrode cost (W $(-1)) 1.9 times greater than the GB-MFC, despite producing 14% less power and 15% less anodic current, while having 2.6 times less anodic surface area, 2.1 times larger charge transfer resistance and an electrical conductivity three orders of magnitude lower. The results demonstrate that inexpensive materials are capable of achieving more cost-effective treatment than high-performing materials despite generating lower power when treating real wastewater. PMID:27395791

  16. ARPA advanced fuel cell development

    SciTech Connect

    Dubois, L.H.

    1995-08-01

    Fuel cell technology is currently being developed at the Advanced Research Projects Agency (ARPA) for several Department of Defense applications where its inherent advantages such as environmental compatibility, high efficiency, and low noise and vibration are overwhelmingly important. These applications range from man-portable power systems of only a few watts output (e.g., for microclimate cooling and as direct battery replacements) to multimegawatt fixed base systems. The ultimate goal of the ARPA program is to develop an efficient, low-temperature fuel cell power system that operates directly on a military logistics fuel (e.g., DF-2 or JP-8). The absence of a fuel reformer will reduce the size, weight, cost, and complexity of such a unit as well as increase its reliability. In order to reach this goal, ARPA is taking a two-fold, intermediate time-frame approach to: (1) develop a viable, low-temperature proton exchange membrane (PEM) fuel cell that operates directly on a simple hydrocarbon fuel (e.g., methanol or trimethoxymethane) and (2) demonstrate a thermally integrated fuel processor/fuel cell power system operating on a military logistics fuel. This latter program involves solid oxide (SOFC), molten carbonate (MCFC), and phosphoric acid (PAFC) fuel cell technologies and concentrates on the development of efficient fuel processors, impurity scrubbers, and systems integration. A complementary program to develop high performance, light weight H{sub 2}/air PEM and SOFC fuel cell stacks is also underway. Several recent successes of these programs will be highlighted.

  17. Fuel Cell Research and Development for Future NASA Missions

    NASA Technical Reports Server (NTRS)

    Manzo, Michelle A.; Hoberecht, Mark; Loyselle, Patricia; Burke, Kenneth; Bents, David; Farmer, Serene; Kohout, Lisa

    2006-01-01

    NASA has been using fuel cell systems since the early days of space flight. Polymer Exchange Membrane Fuel cells provided the primary power for the Gemini and Apollo missions and more recently, alkaline fuel cells serve as the primary power source for the Space Shuttle. NASA's current investments in fuel cell technology support both Exploration and Aeronautics programs. This presentation provides an overview of NASA's fuel cell development programs.

  18. Impacts assessment and trade-offs of fuel cell-based auxiliary power units. Part I: System performance and cost modeling

    NASA Astrophysics Data System (ADS)

    Baratto, Francesco; Diwekar, Urmila M.; Manca, Davide

    Auxiliary power units (APUs) are devices that can provide all or part of the non-propulsion power of a vehicle. They do not replace the main internal combustion engine, but they complement it offering low consumption, high comfort and low emissions during the idling periods of the vehicle. This work presents an integrated framework to evaluate the trade-offs between cost effectiveness, efficiency and health and environmental impacts of fuel cell power systems considering various stages of the life cycle of the device. The integrated framework has six main components, namely system level modeling, cost modeling, environmental impact assessment, health impact assessment, life cycle assessment and multi-objective optimization. In part I of these two papers, concerning the integrated framework, the first two components are described and applied to a solid oxide fuel cell-based auxiliary power unit. All the results are validated with experimental data or other published models.

  19. Efficiency measurement and uncertainty discussion of an electric engine powered by a "self-breathing" and "self-humidified" proton exchange membrane fuel cell.

    PubMed

    Schiavetti, Pierluigi; Del Prete, Za