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hey refer to their tecuwlogy as a “well-kept secret.” But after 30 years of development, fuel cell manufacturers are taking their first steps into the marketplace and looking for recognition. “Fuel cells are usable now . . . with benefits now,” declared Marcus Nurdin, managing director of the World Fuel Cell Council (Frankfurt, Germany), at a recent news conference in New York City. Among the benefits are significant reductions in emissions of CO, and acid rain-producing gases. Fuel cells generate electricity electrochemically. Nurdin describes them as a “kind of neverending battery.” Compared to fossil-fuel power plants, fuel cells emit half as much CO,, as much as 95% less NO,, and virtually no particulates. Moreover, the heat from the electrochemical reaction can be re-
Pdcis articles ore reports of meetings of unusual significance, international or national developments of environmental importonce. significant p u b h c policy developments, and related items.
BY ALAN NEWMAN claimed through cogeneration, providing operating efficiencies as high as 60%. Finally, fuel cells are solidstate devices that operate quietly. Assembled into “stacks,” fuel cell units generate power in the range of 50 kW to tens of MW-less than traditional power plants but sufficient for an office or apartment building, a hospital, electric vehicles, or a small community of homes. Futhermore, their smaller size may he another environmental advantage. With fuel cell stacks distributed throughout urban centers, utilities could generate electricity locally. Energy losses from transmitting electricity through high-voltage lines would be reduced as well as the need for large new power plants. The approach also diminishes electromagnetic fields emanating from high-voltage lines, which may promote certain cancers. Despite these potential advantages, fuel cell manufacturers still face some tough hurdles. On the technical side, the industry needs to set standards and demonstrate the
0013-936X/92/0926-2085$03.00/0 B 1992 American Chemical Society
long-term reliability of fuel CL..~. According to Marino Woo of the Fuji Electric Corporation, “frequent shutdowns and start-ups can affect units.” However, the toughest problem may be economic. The industry, says Nurdin, “is suffering from a classic demand-supply problem.” Fuel cells are currently too expensive to compete successfully in the marketplace: prices won’t drop until production increases and production won’t increase until prices drop. A recent study by the Arthur D. Little company (Cambridge, MA)
Environ. Sci. Technoi., VoI. 26, No. 11, 1992 2085
Frontiers in Molecular Toxxicology n anthology of the most up-to-date information regarding the mechanisms of toxicology and the methods for studying same, Taken from the ACS journal. Chemical Research in Toxicology,the 21 articles were selected both for their timeliness and the quality of their content. Collectively, they convey the sense of excitement that exists when chemistry and toxicology interface. The variety of structural classes of toxic agents and the range of biological effects they induce present an infinite number of interesting challenges involving such techniques of modern mechanistic and theoretical chemistry as structure elucidation, chemical analysis and synthesis, and physical characterization. With that in mind, the editor has grouped the material into four areas of concern: Toxic Agents
A
and Their Actions: Enzymes of Activation, InaCtivation. and Repair: Physical Methods: and Macromolecular Modification. Organic, analytical, biological, and environmental chemists and toxicologists will benefit from this book and its emphasis on chemical
approaches to the solution of toxicologically interesting problems. Lawrence J. Marnett. Editor Vanderbilt University 294 pages (1 992) Paperbound ISBN: 0-8412-2428-5 $26.95 Text: $16.95 American Chemical Society
Distribution Ofice Dept 35 1 IS5 Sixteenth St N W Washington DC 20036 or CALL TOLL FREE
800-227-5558 (in Washington. D.C 872-4363)and use your c x d i t card
2086 Environ. Sci. Technol., Vol. 26,
found that fuel cell stacks could be competitive at $250 to $400 per kW and that such a price would be reached at manufacturing levels of approximately 300 MW annually. Currently, the largest production capacity is about 20 MW, yielding cells costing $2500 per kW for a 200-kW plant. To reach competitive production levels, report co-author W. Peter Teagan recommends that governments provide incentives akin to the 1970s-80s U.S. tax credits for renewable energy. Japan, which has taken the lead in commercializing fuel cells, already follows that path. That country’s powerful Ministry of International Trade and Industry announced last year a goal of 2250 MW of installed fuel cell-generated power by the year 2000 and 8300 MW by 2010. To meet these goals, the Japanese government offers fuel cell purchasers financial incentives through direct credits and a tax credit of about 30%. According to Nurdin, Japan has already completed 20 fuel cell projects and more than 1 0 0 are planned. Japan also boasts the world’s most powerful commercial fuel cell stack, Tokyo Electric Power Company’s 11-MW operation located in Ichihara City on Tokyo Bay. That unit supplies power for about 4000 households. European countries are working on several demonstration fuel cell projects. For instance, a consortium of German companies has funded an ambitious “hydrogen economy” demonstration project in Bavaria (Solar-Wasserstoff-Bayern) that includes a fuel cell using hydrogen electrolyzed from water by sunlight. This project began with $40 million in funding, and recently an additional $47 million was approved for a second phase. Another source of hydrogen, the product of a chloralkali plant, is used to run a 400-kW fuel cell unit in Norway. The United States’ first commercially operating fuel cell was installed in May at the South Coast Air Quality Management District’s headquarters in Diamond Bar, CA. Operating with natural gas, this stack produces 200 kW of power. Southern California Gas Co., which installed the Diamond Bar unit, has purchased another nine units that will be installed around the region over the next two years. Fuel cells could also play a role in transportation. The Department of Energy, working with General Motors, Dow Chemical, and Ballard
No. 11, 1992
Technology, plans to demonstrate a fuel cell-powered car by 1996. Ballard is also developing fuel cell-powered buses for the city of Vancouver, Canada. A prototype is expected to hit the streets this year, and the company plans to have a small fleet of these buses operating by 1995. According to Ballard’s vice president of technology, Keith Prater, fuel cell engines should operate 30,000 hours compared to about 3000 hours for an internal combustion engine. “[The fuel cell engine] is intrinsically a simple device,” claims Prater. With commercialization, the industry has had to make choices about technologies. Fuel cells generate electricity from the reaction of hydrogen or a hydrogen-rich gas (created by sending fuels such as natural gas, alcohols, or even biomass gases through a heat reformer) and oxygen. The dc electrical output is then converted to ac. According to the Arthur D. Little report, fuel cells employing phosphoric acid as the electrolyte are currently the most commercially viable. These operate at about 200 “C with electricity-generating efficiencies of 35-45% (cogeneration raises the efficiency). Future fuel cells might use electrolytes of molten carbonate, technology now in the development stage, or solid oxides-currently considered experimental. Both of these technologies operate at higher temperatures (> 500 “C), and fuel reforming can be incorporated into the cell, increasing the unit’s efficiency and simplicity. (The fuel cells aboard the U.S. Space Shuttle rely on the more expensive alkaline electrolyte design, which operates at about 100 “C.) Just as the technology is evolving, so are the potential applications. For instance, heat from fuel cells could be used by industry to promote chemical reactions or as part of a district heating system. Fuel cells might also power locomotives, especially if magnetically levitated trains ever become a reality. In the meantime, the industry is trying to gain some respect. “A new technology is very difficult,” says Woo. “They haven’t taken us seriously.” However, Nurdin adds, “We are out of the 10-to-15-yearsaway-to-reality syndrome.”
Alan Newman is an associate editor on the Washington staff of ES&T.
