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Tech Briefs
"Ford is trying to explore any promising path that is non-polluting and efficient at the same time," John Wallace, Director of Environmental Vehicles at Ford, said during a media day devoted to the automaker's hydrogen-fuel projects. The world's first family-size fuel-cell research car, P2000 HFC, uses a third-generation Ballard fuel-cell stack, and an advanced Ecostar electric-drive system. In 1993, the electric-drive system on the Ecostar electric van encompassed over 10,000 parts. In contrast, P2000 HFC's electric drive system has fewer than 4000 parts. "It may still sound like a lot, but that's a 65% reduction," said Ross Witschonke, President of Ecostar. P2000 HFC uses 400 cells and three fuel stacks weighing 170 kg (380 lb). The fuel-cell research vehicle has a 0 to 97 km/h (0 to 60 mph) acceleration of 14 seconds, and a limited maximum speed of 145 km/h (90 mph). The one-of-kind prototype—reflecting a $5 to $10 million price tag—rides on a stretched Ford Contour platform. Its 1515-kg (3340-lb) curb weight includes an all-aluminum body and chassis as well as a 16-kg (35-lb) traction inverter module and a 91-kg (200-lb) electric motor/transaxle. Compressed hydrogen gas powers P2000 HFC, but an expected switch to liquid hydrogen, as well as packaging changes, would improve the four-door car's present 169 to 483 km (100 to 300 mi) range. Ford will deliver cars to California's Fuel Cell Partnership in 2000. An expected 45 vehicles, including buses, will be road tested as part of the project. Other companies involved in the validation project include Shell, Texaco, ARCO, Ballard Power Systems, and DaimlerChrysler. It was a Ford and Mobil alliance that netted the breakthrough in the gasoline-to-hydrogen onboard-reforming process for fuel-cell vehicles. The partial oxidation reforming process typically begins at temperatures of 800° to 1300°C (1472° to 2372°F). "While much of the research is still ahead of us, we developed new catalysts that allow the reformation process to begin at much lower temperatures," said Jim Katzer, Mobil's Vice President of Technology. Ford's hydrogen research and development work has gained momentum from North America's first refueling station for liquid or gaseous hydrogen. The pump station also uses more than 1000 feet of underground pipes to deliver liquid or gaseous hydrogen to Ford's dynamometer lab and other testing sites on the Dearborn, MI, engineering campus. In addition to hydrogen fuel cells, Ford has been analyzing hydrogen internal-combustion engines in its dynamometer lab since December 1998. "Because hydrogen is a super dry fuel, the durability of injectors is not what it should be. We haven't fully quantified it yet, but it's a stiction (sticking and friction) issue relating to the moving parts inside the fuel injectors," reported William Stockhausen, Staff Technical Specialist in Ford's Scientific Research Lab. "Since hydrogen fuel does not contain carbon, traditional measurement methods are ineffective. For example, we measure water content or oxygen content concentration in the exhaust. We had to determine which test methods could be trusted and which ones are subject to variation." A hydrogen internal-combustion engine, according to Stockhausen, would achieve 25-30% better fuel efficiency than a conventional internal-combustion engine while producing no hydrocarbons, no carbon monoxide, and no carbon dioxide emissions, while the nitrogen oxide emissions would meet proposed federal standards. As to which hydrogen application will reach the market first, Stockhausen wagers on the internal-combustion engine. "Much sooner than a fuel cell, but it all depends on the infrastructure. A fuel cell, however, is capable of much better fuel efficiency and less NOx," he said. Kami Buchholz |
