LEARN MORE


GM: Going Electric

.

In reviewing the 10 years that he's been pursuing the future for General Motors, Larry Burns, GM vp of Research and Development and Strategic Planning, says that one of the interesting developments that has occurred, and which seems to be on its way to some sort of inflection point, is that there are alterative fuels emerging at a rate such that there will be significant change in the abiding transportation model that is currently 96% dependent on petroleum. Burns has long been GM's point man when it comes to hydrogen fuel cells, which seem to have been eclipsed by the introduction of the Chevy Volt, which uses an internal combustion engine as a means to power a generator that works in concert with an in-development lithium-ion battery system. There is another variant, the Opel Flextreme, which uses a diesel engine. So what you're seeing here is a model that is still predicated on petroleum products. Which might make it seem that the hydrogen-powered fuel cell is no longer in the portfolio.

But that's changed, now that GM has introduced it Cadillac Provoq concept vehicle. It uses the same fundamental E-Flex architecture as the Volt and the Flextreme, but has a fuel cell stack employed. This isn't some sort of vindication for Burns. It is simply that they're looking for energy alternatives, and hydrogen is still in the game. While there are some people who pooh-pooh the whole concept of hydrogen as being an energy source just this side of unobtainium, Burns cites a research report done by two of his colleagues at GM-Britta K. Gross, manager of Hydrogen and Electrical Infrastructure Commercialization and Ian J. Sutherland, Hydrogen Infrastructure Analyst-as well as Dr. Henk Mooiwer of Shell Hydrogen titled "Hydrogen Fueling Infrastructure Assessment." It includes, in effect, a top-10 list that walks through the amount of hydrogen being currently produced (globally: >40 billion kg); the costs associated with producing, distributing and dispensing hydrogen for use in fuel cells vehicles; and how it can be kick-started ("Natural gas provides a well-understood and relatively low-cost source of hydrogen [production of approximately $0.60 per gallon of gasoline equivalent, cost-per-mile basis]"). Importantly: "Bottom line: The hydrogen infrastructure for automobiles is economically viable and doable but requires a collective will by automakers, energy suppliers, and governments to overcome initial capitalization risks, motive early movers, and manage the transition."

GM is putting skin in this game in the form of dedicating an array of resources-human, technical, financial-not only for the hydrogen future, but biofuels, as well. 

Provocative Cadillac. So there's the Provoq. A concept vehicle. It is no mistake that this is a Cadillac rather than a Chevy. Jim Taylor, Cadillac general manager, says that within the GM organization, the brand should "cast a shadow from above." If there is going to be commercially available advanced technology, then it ought to start at Cadillac, whether it is shock absorbers with magneto-rheological fluid, or, eventually, hydrogen-powered vehicles. Cadillac does have a gas-electric hybrid in its offerings, the Escalade with the two-mode system; that's technology also available in models from its sister brands, GMC and Chevy. In the fuel-cell arena, General Motors is doing consumer testing of fuel cell technology by rolling with a fleet of 100 Chevy Equinoxes that are being driven by consumers in New York, Washington, and California for three-month stints; the program is called "Project Driveaway." But Taylor strongly implies that if there is going to be a hydrogen-powered vehicle coming from GM at some point within the next few years for the consumer market-"It's way inside the mechanical bandwidth," he says, indicating that the rocket science is fairly down to earth-it will be a Cadillac.

One interesting aspect of the Provoq is that rather than unveiling it at the North American International Auto Show in Detroit, it made its first public appearance at the Consumer Electronics Show in Las Vegas. During its introduction, GM chairman and CEO Rick Wagoner described it as "another important step in GM's commitment to energy-wise, environmentally conscious, electrically driven vehicles-and the promise of truly sustainable transportation."

Whereas the other vehicles with the E-Flex architecture are on the corporation's small-car platform, the Provoq is on a new global luxury cross-over architecture. Whereas the Equinoxes are using GM's fourth-generation fuel cell, the Provoq has the fifth. There are two 10,000 psi hydrogen storage tanks that provide 13.2 lb. of hydrogen, which when mixed with oxygen in the fuel cell stack located under the hood, generate up to 88 kW of continuous power. There is also a lithium-ion battery pack that can store a total of 9 kWh of electrical energy and provide a peak of 60 kW of power. The electricity is used to power a 70-kW coaxial drive system for the front wheels and individual 40-kW wheel hub motors on each of the rear wheels. The 0 to 60 mph time is said to be 8.5 seconds. The E-Flex system in the Provoq has an expected range of 300 miles per H2 fill up, with 280 miles coming from the stored hydrogen and 20 miles from the stored battery electric energy.

The Lithium-Ion Challenge. Of course, while there are hydrogen infrastructure challenges, there are also lithium-ion battery challenges. General Motors is working with both A123 Systems (www.a123systems.com) and LG Chem (www.lgchem.com) on the development of lithium-ion batteries. The E-Flex was supposed to be ready for production by 2010. There have been some reports that the batteries aren't coming along as quickly as had been expected. Asked about that, Wagoner admits, "2010 was a stretch. It is still a stretch." They are still working toward that time. They are not retreating. "Typically," Wagoner said in his prepared remarks at the CES event, "we develop new technology-like the battery and propulsion system-before we kick-off a production-vehicle program. But the Volt is being developed with the maximum sense of urgency we can muster."

Jon Lauckner, GM vice president of Global Program Management, who is intimately involved in E-Flex developments, points out that there has been a recent development out of Stanford University (www.stanford.edu) of great interest: silicon nanowires. Research led by Yi Cui, assistant professor of material science and engineering, and essentially uses silicon nanowires in an arrangement that, at the microscopic level, at least, resembles a Brillo pad. The advantage of using these silicon nanowires in the battery anode is that they are able to handle plenty of positively charged lithium atoms and when the lithium is drawn off, there isn't the same sort of expansion/shrinkage cycle that it typical of the lifecycle of conventional silicon architectures. The high-performance battery they've developed is shown to have the ability to produce 10 times the amount of electricity generated by conventional lithiumion batteries. And automotive applications are possible. Realize that the lithium-ion battery is key for not only vehicles with hydrogen fuel cells like the Provoq, but for the gasoline engine and diesel engine versions that are the Volt and the Flextreme.
Larry Burns makes an important point about what he sees as the challenges being faced by the auto industry going forward. "Energy diversity is what we need. We should not try to pick 'a winner.' There will be a variety of propulsion systems and sources of energy." He asks, not entirely rhetorically, "Why wouldn't we try to position General Motors to be the technology leader in all of these fronts?"KMK