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The Fuel Cell Glossary was originally prepared by Vicki McConnell, Editor of Fuel Cell Industry Report in 2001 along with valuable input and review from the following industry experts:
Dr. Arnold Miller
FuelCell Propulsion Institute
Denver, Colo.
Paul Bony, Tom Polikalas, and Ron Fleshood
Delta Montrose Electric Association
Montrose, Colo.
Dr. James McElroy
McElroy PEM Technologies LLC
Sheffield, Conn.
Dr. George Maughan
Training Consultants Inc.
Morgantown, W.Va.
Dr. David Edlund
Idatech
Bend, Ore. (2005)
Please note that the Fuel Cell Glossary includes links to information at this site as well as at government, industry and academic sites.
Frequent reference is made to Fuel Cell Industry Report (FCIR) in this text. Subscribers to the print edition of FCIR receive free access to the 500+ articles in the Online Newsletter Archive and may view the articles referenced here (from 2003 to present) by clicking “Current Issue/Archive” on the navigation bar at the right.
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A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
A
Absorption — process in which one substance permeates or is dissolved by another in liquid or solid form.
AC/DC — alternating current/direct current, the general forms of electricity. A fuel cell initially creates direct current that generally is converted (by way of a balance-of-plant component called an inverter) to alternating current for practical use. (See Inverter)
Adsorption — molecules of gases form a thin film on the surface of a liquid or solid.
AFC — alkaline fuel cell, characterized by alkaline electrolyte [circulating KOH, or what is called a "Bacon" cell, comprising an asbestos cloth saturated with KOH] in concentrations of 35% to 85% by weight, and operating temperature ranging from <150°C to ~250°C. First developed in the 1940s, AFCs were used to power a farm tractor in 1959 and by NASA in the space program in the 1960s (e.g., power source for the Eagle spacecraft, 1969, as part of the Apollo program, and operating at 180°C in the Space Shuttle). Companies active in AFC development include Astris Energi Inc. (FCIR online October 2004), www.astris.ca. and Apollo Energy Systems, www.apolloenergysystems.com.
AFV — alternative fuel vehicle, encompassing electric vehicles (EVs), hybrid vehicles (HEVs), fuel cell vehicles (FCVs), and natural gas- and biofuels-powered vehicles (NGVs).
Amps — the volume of electricity flowing through a conductor, can be compared to the gallons per minute (gpm) of water flowing through a pipe.
Anode — one of two conductive electrodes separated by electrolyte within an individual fuel cell (the other electrode being the cathode). While complex multistep processes occur at each electrode, the anode is the electrode at which oxidation takes place. In most fuel cells, hydrogen gas enters at the negatively-charged anode (or in the case of ZAFCs and MAFCs, metallic fuels enter here). Both electrodes contain a catalyst (or electrocatalyst) to accelerate the fuel/air ion reaction. Electrodes are usually seated upon electrode supports, which may be manufactured integral to the electrode itself. (See Catalyst)
APU — auxiliary power unit, a secondary source of power that one might find in a vehicle running various systems, such as heating/air conditioning. BMW has prototyped both PEMFC- and SOFC-powered APUs in vehicles; Freightliner has tested APUs for long-haul semi-tractor/trailer rigs; Honeywell has developed SOFC APUs for light-duty and heavy trucks (FCIR online February 2001, April 2003).
ATR — autothermal reforming. (See Reformer)
Bar — unit of measure that reports pressure. One bar is about 15 pounds per square inch (psi). The air pressure in typical car tires is about 3 bars. High-pressure hydrogen storage tanks to date have been rated to 350 bar (5,000 psi) and 700 bar (10,000 psi). (See Hydrogen storage)
Base load — refers to either the typical minimum electrical power demand placed on a fuel cell system (such as by a home or business run by that fuel cell) or the typical minimum electrical output from a fuel-cell system. In some cases, these values may be the same. A home may have a base-load electrical demand of 400 W, and a residential fuel cell system may have a base-load output of 400 W (net electrical) for a residential application. Base load can fluctuate if electrical power demands increase, and a fuel cell that accommodates this fluctuation is referred to as having the capacity to load follow. (See Load following)
Biofuels — fuels such as ethanol, biodiesel and methanol made from biomass. Biofuels can also be used as a hydrogen feedstock. (See Biomass.)
Biogas — a combustible gas derived from decomposing biological waste. Biogas normally consists of 50 to 60% methane. Land-fill-generated gases fall under this category and could provide a huge resource for biogas as a H2 feedstock.
Biomass — organic matter that can be converted to a renewable liquid, solid or gaseous fuel such as methane or hydrogen. Biomass can be derived from forest and mill residues, agricultural crops and wastes (such as corn stover, alfalfa stems, obsolete seed corn, hulls and nut shells, fibers from sugarcane, straw from rice and wheat), wood and wood wastes (sawdust, timber slash mill scrap), animal wastes, livestock operation residues, aquatic plants, fast-growing trees and plants, and municipal and industrial wastes (FCIR online July 2005).
See a comparative chart of the Biomass Energy Technologies, which are direct combustion, gasification, pyrolysis, anaerobic digestion, ethanol production, biodiesel production, and methanol production, plus an extensive glossary of energy related terms at the Oregon Department of Energy, www.energy.state.or.us/biomass/FuelCell.htm.
The Columbia Boulevard wastewater treatment plant in Portland, Oregon, uses biogas to generate electricity from a phosphoric acid fuel cell (PAFC); the biogas is a byproduct of the sewage treatment process. This is the first installation in the western United States of a fuel cell running on wastewater digester gas; the PAFC was manufactured by ONSI Corp. (now UTC Fuel Cells, www.utcfuelcells.com.) On the East Coast, in Yonkers, New York, similar UTC Fuel Cell PAFCs were the first in that state to be fueled by hydrogen produced from a methane gas byproduct at sewage treatment plants, www.nypa.gov.
In July, 2004, the DOE and Department of Agriculture selected 22 projects to receive $25 million within the Biomass Research and Development Initiative, www.energy.gov. Among those selected was Technology Management of Cleveland, Ohio, for a project involving fuel cell systems operating on 100% bio-liquid fuels. For a further resource on applying biomass technology, see The Brilliance of Bioenergy — In Business and In Practice by Ralph Sims. Published in February, 2002, it is available in hardback from James and James Science Publishers, Ltd., www.jxj.com.
Bipolar plates — flat, gas impermeable, electrically conductive separator between individual fuel cells in a stack, containing "flow fields" on each side (when flow fields are on one side only, the plate is called a separator plate or current collector and is not considered bipolar-- such as the end plates in a fuel cell stack or the two end plates in a single cell that is not integrated into a stack). These flow fields are usually channels machined or molded into the composite, ceramic, or metal plate that carry fuel (usually hydrogen) on one side and oxigen or air on the other side from entry and exit points in the fuel cell. As stated in the U.S. DOE’s 1999 publication, Fuel Cells: Green Power (from the Office of Advanced Automotive Technologies and the Los Alamos National Lab, "the pattern of the flow field in the plate as well as the width and depth of the channels have a large impact on the effectiveness of the distribution of the reactant gases evenly across the active area of the membrane/electrode assembly". (See MEA)
Some of the first carbon composite bipolar plates were prototyped as part of the PNGV effort by the Institute of Gas Technology which has merged with the Gas Technology Institute, www.gastechnology.org. (See PNGV)
Also referred to as flow field plates, bipolar plates (one plate doing the ion-conducting job on both sides) help reduce the size and weight of a total fuel cell stack, remove water produced in the electrochemical reaction (See Water management), assist in heat removal as part of a stack’s thermal management (See Thermal management), and preserve power density (See Power density). For PEMFCs, initial pure graphite plates with machined flow fields have proved expensive; more recent R&D into the use of composite materials is yielding lower cost processes. (See Composite) An analysis system including proprietary film products and an imager from Sensor Products Inc. gives OEMs a tool to help qualify the flatness of bipolar/separator plates both during production and once installed in a fuel cell stack (FCIR online May 2003), www.sensorprod.com. Updates on bipolar plate technology appear in FCIR online March 2003, February 2004, January 2004 and December 2003.
Blackouts, brownouts — an interruption of electrical power due to excessive demand. Brownouts indicate voltage reductions of short duration, whereas blackouts indicate complete loss of power. Rolling blackouts refer to shifts of power loss from one area to another. A company or residence with a primary or backup fuel cell would have an alternative to such power losses from the grid. (See report on major U.S. blackout, FCIR online October 2003).
BOP — balance of plant, those components additional to and integrated with a fuel cell’s primary power module (which is individual fuel cells connected in a "stack") to make up the entire operational system. Can include a fuel processor (See Fuel processor) or fuel reformer (See Reformer), power conditioning components (such as inverters and voltage controls), motors, compressors, blowers and fans, valves and piping, even conventional batteries complementary to the fuel cell stack, and the fuel storage medium. (FCIR online January 2004, February 2004, March 2003, and January 2003).
CARB — California Air Resource Board, instrumental in initiating that state’s Zero Emission Vehicle (ZEV) mandate in 1990 that requires the seven largest automakers (DaimlerChrysler, Ford, General Motors, Honda, Mazda, Nissan, Toyota) to produce a certain percentage of their vehicles to meet ZEV or "clean car" standards. The initial percentage proposed by CARB of OEM ZEV vehicles began at 2% with an increase to 10% over a period of 13 years (2003); it has since been revised. CARB is also a founding member of the California Fuel Cell Partnership (CaFCP), www.arb.ca.gov.
CAFE — corporate average fuel economy, federally mandated miles-per-gallon targets for various categories of vehicles in the U.S. Controversy has erupted over the last several years based on laws passed first in California and then in several other states that required much lower GHG emissions, which ultiimately affects the CAFE targets. GM in particular has taken issue with these state laws overriding the targets now set by the National Highway and Transportation Administration. (FCIR online September 2005).
CaFCP — California Fuel Cell Partnership, formalized in 1999, and considered the preeminent coalition for fuel cell vehicle R&D, now includes members representing automakers, fuel suppliers, fuel cell OEMs, and government agencies. Founding members include Ford, DaimlerChrysler, ARCO, Shell, Texaco, and Ballard Power Systems. A 55,000-sq.-ft. headquarters building was dedicated in West Sacramento in November, 2000, with the rollout of 14 FCVs, www.fuelcellpartnership.org.
Catalyst — materials that increase the rate of chemical reaction across a fuel cell membrane within the membrane electrode assembly (MEA). For PEMFCs, the primary catalyst now used in the MEA is the noble metal, platinum, which has unlimited life (is not consumed in the electrochemical reaction of a fuel cell) and so has the potential to be recycled when the life of the fuel cell ends. The price of an MEA, of which the catalyst is part, can be affected greatly by the loading or amount of catalyst used and the price of the catalyst — platinum currently being at a premium. As such, investigation into non-noble catalysts continues.
Catalyst recycling — in most PEMFCs, the two highly expensive elements in the stack are bipolar plates and the noble metal catalyst (usually platinum) in the membrane electrode assembly (MEA). As such, one key way to contain and reduce costs is to recycle the platinum catalyst. Umicore, one of the world's three leading suppliers of catalysts for automotive applications, claims that 98% of platinum can be recovered from fuel cell catalysts, and the company is set up to do so in small volume at its catalyst recycling plant in Hanau, Germany. However, a widespread system will be necessary throughout the fuel cell industry once mass-production is achieved to have truly cost effective results (FCIR online December, 2003, December 2004, and September 2005), www.umicore.com.
Cathode — one of two conductive electrodes separated by electrolyte within an individual fuel cell (the other electrode being the anode). While complex multi-step processes occur at each electrode, the cathode is the electrode at which reduction occurs. Oxidant enters a fuel cell at the positively-charged cathode. Both electrodes contain a catalyst (or electrocatalyst) to accelerate the fuel/air ion reaction. Electrodes are usually seated upon electrode supports, which may be manufactured integral to the electrode itself.
CFA — community fueling appliances for fueling multiple vehicles at corner stations or in fleets.
Challenge Bibendum — originated by Michelin Tire Company in 1998, this annual world's largest environmental vehicle event tests "clean and green" advanced technology vehicles from international teams consisting of OEMs, designers, energy suppliers, technical leaders, policy makers, universities and government organizations. Vehicles are evaluated in at least 11 different categories, including creative interior and exterior design, emissions, acceleration, braking, handling noise, energy efficiency, and frontal crash test performance. Passenger cars and vans, light trucks (such as GM's S-10 FCV), and commercial class 6-8 heavy trucks and buses compete in the Challenge.
The tests include a road rally to put the vehicles in real world operating conditions.
Bibendum is the French name for the "Michelin Man" logo, an animated tower of tires.
In 2002, the Challenge was held in Germany; in 2003, Bibendum returned to North America, with the event held in Sonoma and San Francisco, Calif. The 2004 Challenge Bibendum took place in Shanghai, China. Ten fuel cell vehicles were featured in the 2001 challenge; Hyundai's Santa Fe FCEV earned gold medals for emissions and noise tests. In 2002 and 2003, DaimlerChrysler's Mercedes Benz F-Cell A-Class vehicle won the Style Advancement and Technical Integration awards for prototype vehicles. Also at the 2003 Challenge, Anuvu introduced its Clean Urban Vehicle (CUV) that it claimed could be purchased for $100,000, www.anuvu.com. Air Products provided the on site H2 fueling stations, www.apci.com; Ballard Power Systems entered four different FCVs, www.ballard.com. At the 2004 Challenge, Michelin introduced its own FCV, the Hy-Light (see FCIR online November 2003 and December 2004). In 2005, Michelin sponsored the Bibendum Forum and Rally in Kyoto, Japan, June 8-9. In 2006, the Challenge will take place June 9-12 in Paris.
CH4 — methane.
CHBC — California Hydrogen Business Council, a nonprofit corporation organized in 1997 to promote the development and use of hydrogen, including providing information and education, commercialization opportunities, utilization and service/supply www.ch2bc.org (FCIR online May 2005).
CHP — combined heat and power, the ability of a fuel cell to provide electric, mechanical and thermal energy simultaneously. Also referred to as "cogen (cogeneration) capability. From an end-use standpoint, a CHP fuel cell unit can provide the primary electricity for a residence or business, and utilize the waste heat from that process for water heating in the home or business (FCIR online March 2004 and June 2005).
CMR — compact mixed-reactant fuel cell stack design from CMR Fuel Cells Ltd., Cambridge, England that eliminates bipolar plates and related seals, substituting selective electrode catalysts on a fully porous anode-electrolyte-cathode assembly that does not require separation of the fuels and oxidants (FCIR online August 2004) www.cmrfuelcells.com.
CNG — compressed natural gas.
CO, CO2 — carbon monoxide, carbon dioxide, gases that can affect the membrane, electrolyte, or both in fuel cells under certain conditions. Carbon dioxide can poison or contaminate an AFC but not a PEMFC, whereas carbon monoxide may contaminate a PEMFC but act as a useful fuel for MCFCs and SOFCs. (See GHG)
Cogen — cogeneration, commonly understood as use of a fuel cell to produce electricity as the primary product and usable heat for space or water heating as the secondary benefit. Recovery of heat energy through cogeneration can boost the efficiency of a fuel cell to 80%. Also can mean combining a fuel cell for backup power with grid-supplied electricity for primary power; or combining a fuel cell for primary power with conventional batteries for backup or peak power; or combining a fuel cell with some other form of renewable energy, such as wind, solar, or geothermal resources. (See CHP)
CTE — coefficient of thermal expansion, refers to dimensional changes within a material for a given unit change of temperature. When combining dissimilar materials, such as a metal with a polymer composite that contains carbon fiber, design compensation is allotted for the different CTE in each material.
Composite — refers to the combining or compositing of best performance benefits from two different materials in one component. In a PEMFC, for example, the polymer composite of carbon fiber/epoxy may be used in the bipolar plates; in a SOFC, the plates and membrane are ceramic while the interconnects may be metallic (making the ultimate fuel cell stack of composite construction).
A polymer composite consists of reinforcing fibers, such as carbon (also called graphite) or glass, and a matrix resin, such as epoxy; when treated under pressure and temperature, properties of both fiber and matrix are retained in the final component. Bulk molding compound (BMC) — made from glass reinforced polyester or vinyl ester, is a form of polymer composite that allows compression molding of lower-cost bipolar plates compared to machined monolithic graphite (FCIR online August 2000 and December 2003), a glass-filled compound (Pemtex from Quantum Composites) is also suitable for injection or injection/compression molding of these plates (FCIR online August 2000), www.premix.com; Energy Partners has developed compression and injection molding processes to produce plates to net shape at reduced cycle time and volume production levels for its PEMFCs (FCIR online April 2000). SGL Carbon Group, a global supplier of bipolar plates, customizes them for many OEMs, with at least one company reporting cutting costs by 90% with molded filled graphite plates compared to machined plates www.sglcarbon.com.
Ballard Power Systems, the industry’s leading PEMFC OEM, formed Ballard Material Products in 2001 after seven years of development efforts on flow-field plates through the acquisition of the carbon products business of Textron Systems and a long-term supply agreement with UCAR Intl. (for its trademarked GRAF-CELL advanced flexible graphite compression molded into flow field plates for Mark 900 PEMFCs) (FCIR online July 2001), www.ballard.com. Carbon products used in fuel cells often originate in powder form. Porvair’s addition of a pyrolysis step to slurry-formed carbon fiber/phenolic preforms that are then subjected to chemical vapor infiltration (CVI) results in a lightweight, low-cost bipolar plate for fuel cell stacks (FCIR online July 2001 and January 2004), www.porvair.com. Cartridge frames for the ReLion’ "hot swap" PEMFC cartridge are made from filled, injection-moldable thermoplastic composites www.relion-inc.com. AFV manufacturers are developing proprietary composites in order to achieve weight and low drag goals for their unique vehicle designs (XCORP and Anuvu Incorporated, www.xcorp.com, www.anuvu.com, (FCIR online August 2001). (See Bipolar plates).
Compressor — a balance-of-plant (BOP) device in a fuel cell system, such as the compressor drive motor from Unique Mobility that delivers compressed air, www.uqm.com.
Converter — a balance-of-plant (BOP) electronic device in a fuel cell system that changes one level of direct current (DC) to another level (DC to DC), primarily as a conditioning of the variable DC output from the stack to the regulated DC required for proper inverter operation. In an inverter, the DC is further changed to alternating current (AC) in a DC-to-AC transition. (See Inverter) This assumes the fuel cell is providing electricity for devices that require AC power; it could also provide electricity in the DC mode, in which case the inverter function would not be required. Whether converted or inverted, current must be conditioned to suit the electrical needs of the end-use application, whether it is a simple electrical motor or a complex utility power grid. Magnetek of Menomonee Falls, WI, is a fuel cell converter supplier, www.magnetekpower.com. (Sometimes the terms converter and inverter are used interchangeably to mean the conversion of DC to AC.)
Current — the movement of an electrical charge (electrons or ions) through a circuit. This charge is originally produced as direct current (DC) that can be inverted to alternating current (AC). (See Inverter)
CUV — Clean Urban Vehicle, a line of vehicles that run on hydrogen and PEMFCs at a cost comparable to a high-end customized sports car (such as a Dodge Viper), developed by Anuvu Incorporated of Sacramento, Calif. (FCIR online June 2004), www.anuvu.com.
DFAFC — direct formic acid fuel cell, which uses concentrated formic acid as a fuel and nanoparticle electrocatalysts in a relatively simple design that can operate within the microwatt to 5-W range at ambient temperature. Renew Power Inc., a subsidiary of Tekion Solutions Inc., is developing DFAFCs (FCIR online September 2004), www.tekion.com.
DFC — direct fuel cell, term used primarily to refer to FuelCell Energy’s molten carbon fuel cell (MCFC) technology. (See MCFC)
DG — distributed generation, strategic and stationary production of electricity from a network of small power systems (with capacity typically less than 30 MWe) at or near individual residences or businesses rather than from a large, centralized power plant. Benefits include:
standby or backup power for uninterrupted service, especially in brownout or blackout conditions;
the potential for combined heat and power (CHP, using waste heat created in the production of electricity);
peak shaving (providing cost-effective means of generating electricity during highest-cost demand periods);
grid support (without expensive upgrades);
stand-alone electricity sources (especially for remote applications).
Fuel cells are especially suited for distributed generation due to their scalability (see Scalability) depending upon voltage and power output needs, efficiency (ability to use waste heat or generate steam), low noise and maintenance (no moving parts in the stack), and eventually the ability of DG fuel cell owners to sell power to the grid during non-peak periods for use during peak periods (peak shaving).
With a DOE grant, Science Application Intl. Corp. (FCIR online November 2000) is developing software that will allow users to evaluate the economic benefits and environmental impacts of a variety of natural gas DG technologies, including as fuel for fuel cells, www.saic.com. (See Software modeling)
The Federal Energy Technology Center (FETC) in Morgantown, WV, is working under DOE funding to develop hybrid fuel cell/gas turbine technology for stationary and DG applications, with the potential of achieving efficiencies in excess of 80%, NOx and CO emissions less than 2 parts per million (ppm) and costs 25% below a comparably-sized fuel cell. (See "Selecting the optimum fuel cell hookup", FCIR online November 2003)
DHFC — direct hydrogen fuel cell, one that utilizes pure hydrogen as fuel as compared to hydrogen produced onboard, or within a fuel cell system, from the reformation of hydrocarbon fuels (gasoline, diesel, propane, natural gas). Currently exhibits the highest levels of system fuel efficiency and power density in terms of direct fuel oxidation. For vehicle applications, the tradeoffs are eliminating the complication in the BOP of a reforming system (positive) with the added weight and space required to store hydrogen in a DHFC system (negative). Scientists at the Massachusetts Institute of Technology predict (FCIR online March 2001) that a direct hydrogen fuel cell hybrid vehicle will be the most energy efficient and lowest emitting vehicle of the AFVs, with nearly 55% lower energy consumption than evolving ICE vehicles.
DLFC — direct liquid fuel cell as designed by Medis Technologies. The company originated its design as a direct methanol fuel cell (DMFC) for portable applications, which debuted in 2001, but switched fuels to 35% ethanol early in its development cycle due to concern about limitations in transporting methanol. As regulations are changing, either fuel can be used in the current DLFC prototypes from the company. The Medis DLFC also uses a proprietary liquid electrolyte and has no membrane as the PEMFC does. In September, 2005, ASE International issued a purchase order totaling $50 million for Medis's Power Pack fuel cell during the first two years of the company's mass production, www.medistechnologies.com.
DMFC — direct methanol fuel cell, where a solution of high-energy, high-density liquid methanol (methyl alcohol) mixed with air demonstrates sufficient reactivity for use directly in a fuel cell without requiring reforming. NAVC’s Future Wheels (see reference at the end of this definition) report states that only modest performance results have been demonstrated by DMFCs compared to PEMFCs, but the potential is being examined in various R&D programs. A DOE study regarding DMFCs conducted in 2000 suggests DMFCs are approaching competitiveness and are not limited to operation within a hybrid power system.
Extensive research into DMFCs and modeling of fuel cells is ongoing at the Institute of Transportation Studies, University of California-Davis, http://fcvcenter.ucdavis.edu/, including focus on understanding methanol crossover and load following behavior. Others involved in DMFC R&D include Medis Technologies, with direct liquid methanol fuel cells, www.medistechnologies.com, and Motorola, www.motorola.com. Energy Visions Inc. in Canada has a proprietary DMFC technology, www.energyvi.com. Methanol supplier Methanex Corp. allied with Statoil BP, BASF, DaimlerChrysler AG, and XCELLSIS to document study research regarding use of methanol fuel in fuel cells (released in 2001) www.methanex.com. The first DMFC powered vehicle was Daimler Chrysler’s NECAR 3 A-Class subcompact (1997).
Suggested references: Future Wheels: Interviews with 44 Global Experts on the Future of Fuel Cells for Transportation and Fuel Cell Infrastructure, 81-page report from the Northeast Advanced Vehicle Consortium, downloadable at no charge from www.NAVC.org; "Looking Beyond the ICE: The Promise of Methanol FCVs," "Methanol Reforming Station Costs" available from the American Methanol Institute, www.methanol.org.
DOC — U.S. Dept. of Commerce, which oversees development of the Partnership for a New Generation of Vehicles program. (See PNGV) In 2002, PNGV was replaced by the Bush Administration’s Freedom Car project.
DOD — U.S. Dept. of Defense, which began funding fuel cell projects in 1993 for defense-related stationary applications (with the first fuel cell online at Vandenberg Air Force Base in California in March 1994), including 30 sites using PAFCs that had abated more than 21,000 lbs. of various air emissions at a cost savings of nearly $4 million, as well as soldier-borne and vehicular systems by January 2000, www.dodfuelcell.com.
DOE — U.S. Dept. of Energy, which has funded multiple fuel cell projects in the billions for portable, stationary, and transportation applications. In 1999, DOE awarded $70 million to 16 fuel cell R&D projects; in 2001, $100 million; in 2005, $78 million, www.doe.gov. (FCIR online July 2005)
DOT — U.S. Dept. of Transportation, another agency in the U.S. government funding vehicular fuel cell development, both in terms of onboard vehicle systems and the infrastructure to support them.
Electrode — an electrically conductive structure in an electrochemical device, such as the anode and cathode in a fuel cell, which transfers electrons to or from reactant atoms or molecules.
Electrolysis — the process by which hydrogen is produced from water. This process is actually the reverse of a fuel cell process, wherein the combination of oxygen and hydrogen produce only the emission of water. The energy required to produce H2 by water electrolysis is about 32.9-kW-hr/kg. Research into lowering the voltage needed for electrolysis - from an average of 1.75 V - is underway, including at the Department of Chemistry, Indian Institute of Technology Madras, which has achieved the H2/water split at around 0.90 V, www.iitm.ac.in. Companies of interest who provide electrolysis technology include Alternate Energy Corp., www.cleanwatts.com; Teledyne Energy Systems Inc., www.teledynees.com; and Stuart Energy, www.stuartenergy.com.
Norsk Hydro has created a "hydrogen island" on Norway’s Utsira island as the world’s first autonomous renewable energy system. The $5.8 million project provides electricity for 10 homes on the island, and includes two 600-kW wind turbines, a hydrogen generator, and a fuel cell. Excess energy produced from the wind turbines can produce H2 via electrolysis. This H2 is then used to power the generator and fuel cell to provide electricity when there is no wind.
In 2004, Honda Motor Co., as part of an alliance with several Japanese companies and the United Nations University, began testing a hydroelectric system to generate H2 for fuel cell vehicles. The system creates the H2 via electrolysis.
Electrolyte — acidic or alkaline medium in liquid or solid form through which hydrogen and oxygen ions are conducted to create an electrochemical reaction, primary means for distinguishing fuel cell types since each fuel cell conducts only one type of electrolyte. In metallic fuel cells, the electrolyte may be a solid. For example, EVionyx Inc. uses a solid state hydroxyl membrane electrolye in the company's proprietary metal/air fuel cell (MAFC), www.evonyx.com
Energy carrier — H2 is often spoken and written of as a fuel, when it is actually a "carrier" that stores energy chemically. This energy is released as electricity in the operation of a fuel cell using hydrogen as one of the key reactants.
EPA — U.S.
Environmental Protection Agency, government agency funding fuel cell research, directed by
the Bush Administration (www.whitehouse.gov/
energy) to form a renewable energy partnership program to help companies buy renewable
energies more easily and promote consumer choice programs toward the environmental
benefits of renewables. Putting fuel cell technology into action, a PSOFC system began powering the EPA’s 140,000 sq ft Environmental Science Center in Maryland in 2002. (See Renewable energy)
Ethanol — a potential alcohol fuel for fuel cells made from the fermentation of starch or sugar sources; according to NAVC’s Future Wheels report (see DMFC), 90% of ethanol produced in the U.S. comes from corn, www.navc.com. When combined with gasoline to form gasohol, ethanol serves as an oxygenate to reduce emissions in ICEs (Henry Ford proposed use of ethanol for fueling early automobiles). Ethanol could provide hydrogen to fuel FCs in areas already using it where an infrastructure is established and/or areas where biomass could be a feedstock. The Renewable Fuels Assn. (RFA), in Washington, DC, promotes the use of ethanol and has formed an RFA Fuel Cell Task Force with members from ethanol fuel suppliers in the U.S. and Canada, fuel cell system OEMs, engineering companies servicing the ethanol industry, and state government agencies. Chairman Jeff Oestmann of Cargill Ethanol states that "the same benefits that ethanol brings to the ICE hold true for fuel cells, including an existing infrastructure delivery system in all 50 U.S. states at the terminal level, and low cost," www.ethanolRFA.org. Nuvera Fuel Cells is also outspoken about ethanol as a fuel cell option, www.nuvera.com.
EV, HEV — electric vehicle, hybrid electric vehicle. Fuel cells are considered electric vehicles since their electrochemical reaction produces electricity, and have been incorporated into a number of hybrid vehicles (see FCEV). For a dedicated EV publication, see Electric Vehicle Progress, www.AltFuels.com, the Electric Drive Transportation Association, www.electricdrive.org, or EV World, www.evworld.com.
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