SemiOT:General Motors rolls fuel cell vehicle project
By Charles J. Murray, EE Times
Jan 17, 2002 (2:50 PM)
URL: eetimes.com
PARK RIDGE, Ill. — Detroit's on-again, off-again love affair with the electric car took a dramatic twist last week, as researchers at General Motors said they have embarked on a fuel cell-based project that could result in nothing short of a reinvention of the automobile.
Known as Autonomy, the concept relies heavily on hydrogen fuels and by-wire technology to create a car that can be transformed from a midsize sedan to a sport utility vehicle to a minivan in less time than it takes to do an oil change. If the program is successful, it could result in a family of vehicle bodies that can be plugged into a few generic chassis, like laptop computers into docking stations. Ultimately, the Autonomy vehicle could eliminate tailpipe emissions and go 300 miles between refueling stops — all without ever burning a drop of gasoline.
"This has great long-term potential to redefine the technology of the automotive industry," said David Cole, director of the Center for Automotive Research (Ann Arbor, Mich.). "It's a glimpse of the future that no one imagined until now."
Autonomy's unveiling, which coincided with a U.S. Department of Energy announcement about accelerated funding for fuel cells, could signal another hard turn in the 100-year journey of the electric automobile. GM officials said the company plans to commit "hundreds of millions" of dollars to the project over the next several years, and hopes to put fuel cell-based vehicles into production within a decade.
The DOE, meanwhile, joined in a partnership with GM, Ford and DaimlerChrysler, announcing a program called FreedomCar that would earmark more funds for fuel cell development, possibly at the expense of research into hybrids and battery-powered vehicles. The amount of the funding will be announced when the Bush administration reveals its new budget on Feb. 4.
Although GM's Autonomy vehicles are at least one to two decades away from reaching significant production levels, experts said the efforts by the giant automaker and the DOE could have broad implications, reaching all the way down to the development of laptop computers and cell phones.
"Advances in one area of fuel cells help the other areas," said Richard Silver, group leader for electronic and electrochemical materials and devices at Los Alamos National Laboratory, which is working on fuel cells. "We're all solving the same scientific and technical problems."
Broader EE role
The new technology could also broaden the role of electrical engineers in the automotive industry, because it would accelerate development of by-wire technology and 42-volt architectures while also giving EEs more responsibility in the area of power train. "If this technology develops as planned, there's no doubt that electrical engineers will play a bigger role," said Bob Vitale, a GM design engineer who heads electrical and by-wire system development for the Autonomy program.
GM engineers said they stumbled on the idea for Autonomy during development sessions approximately 18 months ago. "It hit us like a lightning bolt," Vitale said. "We realized that if you could develop a fuel cell vehicle for full by-wire implementation, you could decouple the vehicle chassis from its body."
When engineers at GM's sprawling Technical Center in Warren, Mich. brainstormed further, they conjured up concepts that had never been imagined before. By eliminating such items as steering columns, brake pedals, brake linkages, master cylinders, hydraulic fluid lines and reservoirs, by-wire technology could enable a self-contained chassis that could be detached from a vehicle body without difficulty. At the same time, the team saw that fuel cells would enable them to eliminate traditional engine compartments, thus freeing up the design of the vehicle bodies.
As a result, the engineering team saw dozens of new possibilities. A customer could buy a chassis that would last for 20 years or more, but change vehicle bodies every few years as their needs changed. Or they could purchase one chassis and two bodies, then switch back and forth when they moved from, say, city to cross-country driving. Engineers even considered the possibility of mass-producing the chassis in the United States, then shipping it abroad so that automakers in other countries could plug their own proprietary bodies onto the GM platform.
"Today, only 12 percent of the world's population drives automobiles," Vitale said. "With this technology, there's potential to reach the other 88 percent."
Unproven technologies
The concept, however, rests atop two unproven, emerging technologies.
Fuel cells, which typically use hydrogen as a catalyst to produce electricity, water and heat, are far more expensive than internal combustion engines. They are as yet unproven over long periods of time, their failure mechanisms are said to be largely unknown and they lack the refueling infrastructure that would be needed for widespread adoption.
Furthermore, engineers are as yet unsure whether the new breed of vehicles would burn gaseous or solid hydrogen, or whether they would use methanol- or ethanol-based fuels along with a reforming process. Whichever type of fuel is used, engineers say that cost will still loom as a critical issue.
"In the last five years, fuel cell power trains have dropped from being 1,000 times as expensive as an internal combustion engine to about 10 times as expensive," noted Cole of the Center for Automotive Research. "But they've still got to come down to be roughly comparable to an [internal-combustion] engine in cost. They have a long way to go."
By-wire technologies, which include steer-by-wire, brake-by-wire, throttle-by-wire and suspension-by-wire, are further along than fuel cells, but still years away from large-scale production. Because such systems lack the inherent redundancies of hydraulic-based technologies, engineers are still hard at work on the development of time-triggered, safety-critical data bus architectures that would ensure safe message passing.
Such technologies, however, are the key enablers for GM's new, modular concept. That's why GM has accelerated its efforts with suppliers in both arenas, its engineers said. The giant automaker has formed an alliance with Hydrogenics Corp., a fuel cell technology company that makes proton-exchange membranes that serve as a key component of the electrochemical reaction in fuel cells. It has also partnered with Quantum Technologies Inc. to develop hydrogen storage devices, which will be critical if 5,000-psi gaseous hydrogen is employed as a fuel.
In addition, GM is teaming with Giner Inc. on hydrogen generation for refueling systems, General Hydrogen on infrastructure issues and Suzuki Motor Corp. on the entire fuel cell system.
For further development of by-wire technologies, GM is also working with SKF USA Inc. (Norristown, Pa.). SKF, which has produced fly-by-wire systems for Airbus for more than a decade, last year introduced the FILO by-wire car at the Geneva Motor Show.
"We've all become accustomed to by-wire technologies in aircraft," said Vitale of GM. "It's our intention to take those basic systems and improve upon them for our applications."
Rough track
In moving its electric-car research toward fuel cells and away from hybrids and pure battery-powered vehicles, GM joins other domestic automakers. In December, DaimlerChrysler (Auburn Hills, Mich.) unveiled the Chrysler Town & Country Natrium, a fuel cell-powered vehicle. In all, DaimlerChrysler has now introduced five generations of such vehicles, using fuels ranging from compressed gaseous hydrogen to converted methanol. The company claims that it will have invested $1.4 billion in fuel cell development by the time initial products come to market.
Similarly, Ford Motor Co. (Dearborn, Mich.) set a national fuel cell endurance record last October when its P2000 vehicle traveled 1,390 miles in one day, stopping only for refueling. Ford has also worked at developing infrastructure technology, demonstrating a hydrogen-refueling system for internal combustion engines last year.
Despite all those efforts, experts say that automotive fuel cells are much further from reaching production than fuel cells for consumer devices. Companies such as Manhattan Scientifics Inc. (Los Alamos, N.M.) and Medis Technologies Ltd. (New York) plan to introduce fuel cell technologies for consumer devices, such as laptop computers and handheld phones. The earliest of those technologies will be fuel cell-based battery chargers, which could come out as soon as the end of this year. Los Alamos National Laboratory has also worked with Motorola Inc. on a fuel-cell-on-a-chip technology.
No one, however, is expecting such early successes within the automotive community. "Automotive is going to be the most difficult application for fuel cell technology," said Silver of Los Alamos National Laboratory. "The weight and durability requirements are very severe."
That's why many experts in the electric-car community are concerned about the Department of Energy plan to abandon the Partnership for a New Generation of Vehicles (PNGV) in favor of the FreedomCar program. PNGV called for development of vehicles, such as hybrid electric-internal combustion engine technologies, as a means of reaching 80-mpg fuel economies in the near future.
That concern is aggravated by recent lawsuits filed by General Motors and DaimlerChrysler against the state of California, which is trying to force the automakers to sell zero-emission vehicles in that state.
"I'll bet that seven or eight years from now, this hydrogen program will be just like PNGV — some nifty technology that costs way more than anyone could afford," said Greg Hanssen, co-chairman of the Production Electric Vehicle Drivers Coalition (Irvine, Calif.). "How does that help the environment?" |
