Wheels: Fuel Cell Theory
If the decision is left to a team of eight MIT graduate students, the first hydrogen-powered General Motors vehicle will be available for purchase in 2010, and it will not be a minivan, SUV, or economy sedan like the hybrid Toyota Prius. Instead, it will be a $50,000 Cadillac sport sedan with the equivalent of 280 hp, a 150-mph top speed, and enough acceleration to singe the tires off any 5 Series that rolls off BMW’s production line. The car, powered by fuel cells that combine hydrogen and oxygen to create electricity, will emit water droplets instead of greenhouse gases, run quieter than a whisper, generate enough electrical power to run an entire home, and still be sprinting when vehicles with traditional internal combustion engines are limping to the junkyard.
The students defeated five other teams from MIT’s Sloan School of Management in a competition held earlier this year in Cambridge, Mass., where the objective was to design and market a 2010 model year fuel cell car for GM. After selecting the 5 Series as the benchmark (in their surveys, the students discovered that the BMW sedan was a popular choice for their target market), the winning team created its virtual vehicle assuming that the costs of fuel cell technology will decline dramatically and a national infrastructure of hydrogen filling stations will exist—two scenarios that skeptics identify as doubtful if not impossible. Depending on the source—auto manufacturers, energy providers, think tanks—the cost of building such a framework would be from $10 billion (according to GM) to as much as $500 billion (Argonne National Laboratory, a U.S. Department of Energy research center), making the hydrogen effort a modern-day equivalent of constructing the country’s interstate highway system.
Despite these financial stop signs, GM, along with several other manufacturers, has constructed concept fuel cell vehicles that hint at what the future might hold. In Washington, D.C., GM is hosting test-drives of its HydroGen3, a hydrogen-powered Opel Zafira minivan approved for street use by the National Highway Traffic Safety Administration. GM’s AUTOnomy, a radical concept car released in 2002, is built around a fuel cell stack and features drive-by-wire technology that replaces mechanical linkages with electrical signals. Hy-wire, another by-wire vehicle from GM, does not have accelerator or brake pedals; instead, throttles for acceleration and braking, similar to those found on a motorcycle, have been built into the handles of the device that serves as a type of steering wheel. “Our ultimate goal,” says Elizabeth Lowery, GM vice president of environment and energy, “is to reinvent the automobile.”
If this is so, then a high-performance, hydrogen-powered Cadillac with no internal combustion engine and no emissions could serve as the flagship for GM’s proposed revolution. However, in contrast to the MIT students’ virtual vehicle, the automaker’s present interpretations of tomorrow’s motoring suffer from what generously could be called limitations. AUTOnomy is a stationary show car, and HydroGen3, during a recent test-drive on Washington’s Rock Creek Parkway, crawled to a stop when its fuel cell stack quit unexpectedly. (An onboard engineer quickly solved the problem by punching several buttons on the dashboard computer.) Hy-wire, after an hour of low-speed parking-lot maneuvers during an outdoor demonstration at MIT, was rushed under an overhang as soon as a few sprinkles fell from the sky. As one GM engineer confessed, “It does not like the rain.”
The obstacles that threaten the production of fuel cell cars and the construction of an accompanying infrastructure have done nothing to discourage automakers, energy providers, and federal programs from tilting at the hydrogen windmill. Raj Choudhury, manager of operations and policy for GM’s fuel cell program, says the corporation spends 25 percent of its annual research and development budget on advancing fuel cell technology. Energy companies including BP, Shell Hydrogen, and ChevronTexaco are building hydrogen fueling stations in Iceland and Washington, D.C., and working with lawmakers to establish international regulations and standards for these establishments. In April, the Department of Energy awarded a $350 million grant to a consortium of companies and research groups to continue their work on hydrogen technology.
Such an investment by the government is not difficult to justify. An increased use of hydrogen would reduce the country’s dependence on foreign oil, the argument goes, easing political tensions associated with the resource. Furthermore, elimination of greenhouse gas emissions associated with gasoline-powered vehicles would reduce health concerns and decelerate the rate of global warming. And finally, at some point, the world’s oil supply will run dry. “Hydrogen is the fuel of the future,” says Choudhury. “We know intuitively—without prognosticating on when production will peak—that crude oil is a finite resource.”
Hydrogen, on the other hand, can be produced through renewable resources: water, wind, and solar power. If the necessary improvements are made to electrolysis technology, luxury cars could one day run on hydrogen produced at a California wind farm. Such a scenario, however, remains only a remote possibility. “It would take dramatic reductions in the cost of these technologies, on the order of five- to tenfold of the production and equipment,” says Phillip Baxley, Shell Hydrogen’s vice president of business development. “Right now, we don’t know how that would be done. We remain hopeful that we can do that in the next 10 to 20 years.”
Hydrogen is the planet’s most abundant element but it is usually bonded with carbon, nitrogen, oxygen, and other elements, and requires expensive and energy-consuming efforts to isolate. Currently, more than 90 percent of the world’s commercial hydrogen supply is produced by burning natural gas. The most common method of production involves a process called methane reforming, in which natural gas is heated to isolate hydrogen as well as carbon dioxide, an unwanted by-product of the procedure.
Aboard HydroGen3, hydrogen enters the minivan’s centerpiece: a silver box located under the hood that contains a stack of 200 fuel cells. Within the stack, hydrogen combines with oxygen to create electricity and water; the electricity powers the car’s electric motor, while the water is emitted through the tailpipe in liquid form. The 200 fuel cells generate 94 kilowatts of power, which is equivalent to approximately 100 hp in a traditional vehicle. HydroGen3 is hardly a screamer, but the minivan accelerates smoothly and keeps up with the flow of traffic, its Rock Creek Parkway malfunction notwithstanding.
The vehicle’s docile nature, however, is the exact characteristic that BMW, the manufacturer that the MIT students targeted in their study, wants to avoid. The German automaker has built several hydrogen-powered 7 Series sedans as test vehicles, but they feature traditional internal combustion engines instead of fuel cells. While BMW will continue its research of hydrogen as an alternative fuel, the company has no plans to replace the internal combustion engine with fuel cells. “A fuel cell car feels like an electrical car,” says BMW Chairman Helmut Panke. “There is no exciting acceleration, no exciting dynamic, whereas the ICE [internal combustion engine] has a special dynamic feeling. When you accelerate, you notice how the car picks up.”
In theory, GM could boost the power of HydroGen3 to provide acceleration similar to that of a supercar. If cost were not a consideration, GM could place hundreds of additional fuel cells, which do not necessarily have to be stored under the hood, in the trunk, under the seats, or in the chassis of the vehicle. Such is the design of Hy-wire, which houses 200 fuel cells, three tanks of compressed hydrogen, and an electrical motor in the vehicle’s 11-inch-thick chassis, which resembles a skateboard. This layout enables GM to eliminate the traditional engine compartment.
The flexibility afforded by this design is seemingly limitless. A manufacturer seeking more power from an internal combustion engine would have to increase the block’s size, alter the layout of the engine compartment to make room for the additional girth, and possibly introduce an entirely new production line to complete the car. With the fuel cell car, GM could simply add more fuel cells to increase the car’s power without increasing its emissions or reducing its mileage. “It just so happens that the attributes they’re seeking require tremendous inputs of power,” Choudhury says of luxury car drivers, “which translate to high fuel consumption. That’s tied to a large body, more weight, more fuel required to move it, and more entertainment attributes. But if we look at something like a peppy luxury car, maximum torque at zero rpm is something we could achieve. It could be very attractive to people.”
GM is even imagining a future in which a chassis such as Hy-wire’s could serve as the foundation for multiple vehicles. A consumer could purchase different body types—sports car, sedan, wagon—and mount a particular body to his or her platform depending on the style of car desired for that day. To give a car a sporty feel, an owner could download software that would adapt the chassis for a tighter and racier setup.
Such are the theoretical possibilities. The reality is that the prices of researching and developing the technology and building an infrastructure might be prohibitive without substantial government funding; that energy companies have yet to agree on even the nozzle design of a hydrogen pump; and that many consumers associate fuel cell cars with the battery-operated electric vehicles of the 1990s, which, while forgoing fossil fuels and producing zero emissions, frustrated drivers with their limited range, feeble power, and prolonged recharging periods. There is also a perception that hydrogen’s combustibility would make it more lethal than gasoline in an accident, although Choudhury says that because of its lighter-than-air density, hydrogen would rise into the air instead of pooling under a car near a possible ignition source.
At the same time, automakers are struggling with the limitations of hydrogen storage solutions—HydroGen3’s range is only 250 miles—and the current stratospheric costs of constructing the vehicles. GM spent more than $1 million building each of its HydroGen3 minivans, and according to GM’s market research, consumers are not willing to pay a “green premium,” the extra cost of owning an environmentally friendly vehicle. For production to become a possibility, GM has concluded, the cost of fuel cell technology must be reduced by a factor of 10.
To find a way to make production a possibility by its self-imposed deadline of 2010, GM is considering ideas from a variety of sources, including the MIT students. Glen Urban, a professor of marketing at the school, approached GM North America President Gary Cowger, a Sloan graduate, with the idea of using the company’s fuel cell project as the primary case study for Design and Marketing New Products, his graduate-level course. GM agreed, briefing the students with an introductory presentation and providing them with reading materials and case studies. (The students had to sign confidentiality agreements before starting the project.) Like GM’s current objective, the students had to select a design for a hydrogen-powered car and market it for a 2010 launch.
One team decided to launch a full-size SUV, touting its size, safety, and power. Another team designed a car aimed at soccer moms that could haul large numbers of passengers and double as an entertainment center. But the presentation that grabbed Urban’s attention was the Cadillac sport sedan. After conducting surveys with recent Sloan graduates, many of whom worked in the financial consulting and investment banking fields, the team came to the same conclusion as GM’s market research demonstrated: Prospective buyers would not pay a premium for an environmentally friendly car. However, the surveys also concluded that affluent consumers would pay extra for higher performance, just as they currently do for luxury sedans and sports cars.
The students therefore designed a sport sedan with a spacious interior, by-wire technology, and neck-snapping acceleration. After briefly considering the Saab nameplate for the car, the team chose to market it as a Cadillac, surmising that the brand’s recent resurgence would continue through 2010. “If you have a good brand, you’re drawing from a pool of goodwill from the past,” Urban explains. “If you’re introducing a new brand, you have to create that. That might cost $100 million. If Cadillac fits, you’re saving a lot of money, because you don’t have to do the ground-zero advertising. You know the brand is good. Ten years ago, it would have been the absolute worst brand. It was a dying brand of old folks. Now all the cars are new. Every car is edgy and young-looking. Sales are going up.”
Among other factors, the reason that Urban, his teaching assistants, and GM executives selected the Cadillac as the winning design is because they thought the car would sell. But of course before anyone can purchase such a vehicle, many more will have to buy into the idea of hydrogen cars.