August 7, 2001

Fresh fuel cell breakthroughs

GM Unveils First Prototype with On-Board Gasoline Processor

Stationary fuel-cell power unit also on show in Traverse City

Rüsselsheim/Detroit. The development team at GAPC (GM and Opel's joint Global Alternative Propulsion Center) has achieved a further success on the way to producing a marketable fuel cell vehicle. Yesterday, at an automotive management conference in Traverse City near Detroit, Michigan, the US car manufacturer presented the world's first gasoline fuel processor for fuel cell propulsion, packaged in a Chevrolet S pick-up truck. The Gen III processor extracts hydrogen from the fossil fuel to feed the fuel cell stack. The prototype features an optimized fuel cell stack, which, in conjunction with the processor, generates 25 percent more power, is far more compact and weighs half as much as its predecessor. Alternative propulsion specialists at GAPC regard on-board gasoline powered fuel cells as an interim strategy until an effective hydrogen infrastructure is in place.

Apart from the use of the fuel cell technology in vehicles, General Motors also showed possibilities for its stationary use: In Traverse City, Larry Burns, GM Vice President for research and development and product planning, presented the prototype of a stationary fuel cell generator which would be suitable, for example, for businesses, office complexes, hospitals and possibly even for home owners. The stationary unit is capable of running on natural gas, methane or gasoline and incorporates the same fuel processor and stack technology used on experimental vehicles to convert gasoline into a high-quality stream of hydrogen that powers the fuel cell.

Gen III Gasoline Processor: Less Space Needed, Quicker Start-Up

Compared with the first purely stationary unit shown in Fall 2000, the development team has made the new mobile Gen III gasoline processor 300 percent smaller, without sacrificing efficiency. The on-board processor, which was also developed in cooperation with Exxon Mobil, has a much shorter warm-up time than its predecessor, taking just three minutes to start instead of the previous 12 to 15. The Gen III has a peak efficiency of 80 percent. The hydrogen produced by the gasoline processor reacts in the fuel cell with oxygen, generating the electricity that powers an electric motor. This breakthrough with gasoline reforming is key to the future market launch of fuel cell vehicles, which have virtually no pollutant emissions and comparatively low CO2 emissions. It makes it possible to use the same filling station infrastructure as for cars with a combustion engine. "Through this new development, fuel cell technology could become a marketable proposition before the end of the decade", said Larry Burns at the Conference.

The fuel cell unit used in the prototype based on the Chevrolet S10 pick-up truck and developed by the specialists at the Global Alternative Propulsion Center, generates 25 kW and weighs 86 kilograms. This means it is only half the weight of its predecessor. Because of its compactness and comparative lightness, it gets very close to the demands of the engineers and car designers for optimum packaging, and should provide a significant boost to the development of future mobile and stationary fuel cell units. Researchers at GAPC are testing a complete gasoline processor fuel cell system that they believe can reach nearly 40 percent efficiency. For comparison, an optimally functioning diesel engine manages around 33 percent and gasoline around 27 percent. Another long-term goal is to develop a processor that can start in less than 20 seconds.

Fuel Cell Generator: Stationary Unit Opens up Fresh Perspectives

To illustrate just how versatile this new fuel cell technology is, GM also unveiled in Traverse City a stationary fuel cell generator, also developed by the GAPC specialists. At the heart of the environmentally compatible, almost silent unit is a compact 5.3 kW stack. The same fuel processor is used as in the mobile prototype, but it can extract the hydrogen it needs to generate the electricity in the fuel cell not only from gasoline, but also from methane or natural gas. The thinking behind it is that a distribution network already exists in the United States for natural gas, and most homes there are heated with it. Consequently, it would be an easy transition for consumers.

The target group for the innovative unit includes businesses and public amenities such as hospitals, but private homes with a natural gas connection would also be ideal. GM's mini power plant, which has already proved itself in a six-month trial at its research facility in Rochester, NY, could serve as a backup generator for California subdivisions at risk of losing power because of common blackouts or other bottlenecks in power supply. GM Vice President, Larry Burns, thinks it possible that stationary units could actually be on the market before the first fuel cell cars. This would also be an advantage in terms of the technology's acceptance: "It would get people comfortable with fuel cells so that by the time they get introduced into automobiles, it won't be any big deal," says Burns. To enable GM to begin marketing its small fuel cell generator as soon as possible, the company intends to conclude a strategic alliance with a partner.

The engineers and scientists at the three GAPC facilities in Mainz-Kastel (Germany), and Rochester (New York) and Warren (Michigan) in the United States have set themselves a number of targets along the way to getting the fuel cell technology ready for market. The 300 or so employees are focusing their attention above all on greater durability of the systems, further miniaturization, shortening the warm-up times, and reducing costs. Fuel cells remain roughly ten times the cost needed for volume production. But the cost has been cut considerably as GM has beefed up its research and development efforts. Fifteen years ago, fuel cells were 1000 times too expensive. Says Larry Burns: "Of course there's a long way to go on several fronts. We are, after all, undertaking a historic change in transportation and propulsion technology, but we're doing it the right way, not trying to win a marathon in the second mile."