The Holy Grail Fuel Cell Vehicles

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Fuel cell vehicles build on battery electric and hybrid electric technology. The concept is simple: fuel cells convert chemical fuels into electricity without combustion (see figure 2.4). While a number of distinct fuel cell technologies exist, the automotive world has settled on a design that combines hydrogen with oxygen from the air and does not operate at high temperatures.38 Other fuel cell technologies have been rejected because they require pure oxygen, instead of breathable air, and therefore are too expensive, or because they operate at high temperatures, creating safety concerns and requiring long start-up times.

Despite proclamations of the imminent commercialization of fuel cell vehicles, beginning with Daimler-Benz in 1997, their expected date keeps slipping. As this book is written, the most optimistic pronouncements are for limited commercialization to begin around 2015.

Hydrogen fuel enters on one side of the fuel cell (anode) and oxygen from air enters on the other side (anode).

Hydrogen Hydrogen gas flow field

Backing layers

(oxygen)

Hydrogen is split into positively charged ions and negatively charged electrons by a platinum catalyst.

Hydrogen Hydrogen gas flow field

Backing layers

(oxygen)

Hydrogen is split into positively charged ions and negatively charged electrons by a platinum catalyst.

Oxygen flow field

The polymer electrolyte membrane (PEM) allows positively charged ions to pass to the cathode while negatively charged electrons create an electric current while traveling along an external circuit.

FIGURE 2.4 How fuel cells work. Source: U.S. Department of Energy, www.fueleconomy.gov, with authors' contributions.

Oxygen flow field

The polymer electrolyte membrane (PEM) allows positively charged ions to pass to the cathode while negatively charged electrons create an electric current while traveling along an external circuit.

Unused hydrogen gas Anode

Water is formed when the hydrogen and oxygen combine.

FIGURE 2.4 How fuel cells work. Source: U.S. Department of Energy, www.fueleconomy.gov, with authors' contributions.

Neither fuel cells nor hydrogen fuel are novel ideas. The first fuel cell was built by Sir William Grove in 1843. But it lay fallow until the late 1950s, when fuel cells began to be developed for use in space missions. They were the best option for producing electricity in a compact, efficient, and safe fashion. The first use of fuel cells in vehicles was in an experimental farm tractor in 1959. In the 1960s, GM began experimenting with fuel cell technology, demonstrating the world's first drivable fuel cell passenger vehicle in 1966. But interest in fuel cell vehicles quickly evaporated, the result of cheap oil, continuing improvements in combustion engines, an increasing appreciation of the costs and technical challenges of mobile fuel cells, and diversion of automotive R&D to the more immediate challenges of vehicle safety and tailpipe emissions. Vehicle fuel cells went dormant once again.

It was California's zero-emission vehicle rule of 1990 that pulled fuel cells and hydrogen back into the automotive world, though not directly or immediately. When the major automakers all came to the conclusion soon after 1990 that battery electric vehicles weren't ready for prime time, they began frantically searching for alternatives. The first glimmer of hope came from Ballard, a small start-up company in Vancouver, Canada, that exhilarated the automotive world in 1993 with the first fully operational fuel cell vehicle, a bus.

The next big event was the stunning announcement in 1997 by Dr. Ferdinand Panik of Daimler-Benz that the company planned to sell 40,000 fuel cell cars in 2004, plus 80,000 fuel cell engine systems to other automakers, ramping up to 100,000 fuel cell cars and 200,000 fuel cell systems by 2006. Panik's announcement reverberated through the boardrooms of Detroit and Tokyo. The American automakers had pushed fuel cells and hydrogen to the back burner when they had chosen to emphasize diesel hybrids in the PNGV program mentioned earlier. Now everything changed. Fuel cells moved to the forefront.

Along with Ford, Daimler-Benz purchased controlling shares of Ballard in 1998, with the intent of using Ballard as their fuel cell supplier. A mad rush to develop fuel cell vehicles followed. At first, it was widely believed that fuel cell technology was so complex and so alien to automakers that they would rely on a few specialized fuel cell suppliers. It turned out very differently. Less than a decade later, Daimler-Benz, GM, Honda, Nissan, and Toyota all had developed in-house fuel cells. Only Ford among the biggest companies remained dependent on an outside supplier, sticking with Ballard. These automakers, with the exception of Ford, were each spending in the range of $100 to $200 million per year on fuel cell R&D through the first decade of this century (which might be a lot or a little, depending on one's perspective, but was much more than they were spending on any other alternative fuel option and much more than governments were spending).

The symbiotic brother of fuel cells, hydrogen fuel, was embraced more slowly. It had been dreamed of as the ultimate fuel since the days of Jules Verne but remained largely ignored until automotive fuel cells emerged in the 1990s. Initially, automakers collaborated with oil companies to develop small reformer devices—essentially miniature-mobile petrochemical refiner-ies—that could be used on vehicles to convert methanol or gasoline into hydrogen. Automakers were worried it would take too long to develop a hydrogen energy refueling system and that onboard hydrogen storage would be too difficult. But the complexity, danger, and cost of fuel reformers soon convinced all automakers to discard them and focus exclusively on the use of hydrogen. Using hydrogen as fuel leads to simpler fuel cell designs, less cost for the fuel cell system, and greater energy efficiency than onboard reformation of liquid fuels.

Through it all, hydrogen fuel cell vehicles retain one important edge over battery electric vehicles and plug-in hybrids: they're preferred by most of the large automotive companies. The principal attraction of fuel cells is their extraordinary energy efficiency, two to three times better than gasoline engines. They're also quiet, are relatively quick to refuel (though not as fast as gasoline), and have longer driving ranges per fill-up than battery electric vehicles. And they produce zero tailpipe emissions, which, as the automakers like to say, "takes the car out of the environmental equation." No longer would car manufacturers need to spend billions of dollars improving and warranting emission control technology and employ hundreds of expensive engineers to test and validate the technology for the government.

An additional key feature is the ability to generate electricity onboard for purposes other than propulsion. This attribute, sometimes referred to as "mobile electricity," may prove most pivotal in determining the success of fuel cell vehicles (and other electric-drive technologies that produce or store large amounts of electricity onboard). It opens up a new array of possibilities. For the first time, travelers would be able to use high-power devices in vehicles, from hair dryers to espresso machines. The vehicles could power backyard equipment, construction tools, or virtually any other device at remote sites. They could also provide backup power to homes or commercial buildings during blackouts. They could sell power to electric utilities during peak usage, generating additional revenue for owners.39 The opportunities to create new uses for the mobile electricity are virtually limitless.

Still another attraction is design flexibility. In today's internal combustion engine vehicles, designers must work around an awkwardly shaped engine, a large radiator, a protruding steering wheel that physically connects to the wheels, and a mechanical driveline that extends down the middle of the vehicle (on four-wheel-drive and rear-wheel-drive vehicles). Fuel cell vehicles open up the design envelope for automotive designers because they allow total electrification of vehicle functions and because the entire fuel cell system can be packaged into a thin chassis. GM has demonstrated this "skateboard" design in operating prototypes. Its first-generation prototype had an 11-inch-thick chassis; the goal is to reduce it to six inches. With the skateboard chassis, automotive designers can rethink the entire design of the vehicle, including placement of seats.

The skateboard design, along with the onboard electrification, provides still another benefit to automakers. It allows them to standardize vehicle platforms and thereby reduce manufacturing costs. They might need only three distinct platforms, for short, medium, and large vehicles, rather than the 20 or so they now require. The short platform might be used, for instance, for sports cars, compact cars, small vans, and small pickups. Software and a bigger or smaller fuel cell system would be used to create different ride qualities and performance. Software could be used to create taut handling for the sports car, gentle suspension for a plush compact, and sturdy suspension for the utilitarian pickups. Automakers could dramatically reduce manufacturing costs and create a more personalized vehicle.

Some of these fuel cell attractions, especially mobile electricity, carry over to battery electrics and plug-in hybrids. Overall, though, the consumer and manufacturer advantages of fuel cells are unmatched by the other electric-drive options. It's no wonder automakers are so enamored of fuel cells.

There are downsides, though. One is cost. Although steady, even sensational, improvements have been made, fuel cell vehicles face stiff competition from the entrenched technology, internal combustion engine vehicles. Today's gasoline vehicles benefit from more than a hundred years of steady improvements in design and manufacturability as well as huge economies of scale. In the late 1990s, the cost of fuel cell vehicles was projected to be at least a hundred times higher than internal combustion engine systems; by the early 2000s, the costs were estimated to be 10 times higher, and by 2007 they were estimated to be just two to three times greater. But for these costs to be realized, fuel cell systems must be produced in large volume. As with hybrids, it takes time to build manufacturing capability and markets. One doesn't leap from hundreds of demonstration vehicles to tens of thousands. Even in the best of worlds, early fuel cell vehicles will be very expensive—for whichever automaker is brave enough to take the leap. In any case, huge amounts of engineering are still needed to improve manufac-turability, ensure long life and reliability, and enable operation at very hot and very cold temperatures.

The second challenge is fuel—supplying it and storing it onboard the vehicle. Although automakers prefer hydrogen for fuel cell vehicles, fuel suppliers prefer liquids because they're easier to handle. Hydrogen is difficult to transport and store, poses safety risks when handling, and would require an entirely new fuel distribution system (as elaborated on in chapter 4). The issue of fuel supply comes down to resource commitment. Many carmakers have committed themselves to fuel cell technology and are quickly mastering it. But their business is building cars, not retail fuel stations. Who is committed to the business of hydrogen fuel? Oil companies are ambivalent, ready and willing to take on hydrogen distribution when they see market demand. They're not inclined to lead. While automakers see a benefit in being first into the market, as Toyota was with hybrids, oil companies do not. Oil companies don't anticipate that building a large number of hydrogen fuel stations will create a halo for them.

Hydrogen storage technology is also missing champions and investors. No well-endowed industry is taking on the challenge of hydrogen storage. The conventional approach today is to compress the gas. But hydrogen is so light that extremely high pressure is needed, requiring large amounts of energy to compress it and expensive tanks to withstand the pressure. Innovative ways to store hydrogen more efficiently and economically are under development. The U.S. government stepped into the void, ramping up funding of hydrogen storage R&D at national labs and universities beginning in 2004. But if there's any lesson in innovation theory, it's that private resources dwarf public resources and that universities and national labs may excel at basic science but are lousy at bringing products to market. Compressed storage will probably be adequate initially, allowing driving ranges of up to 300 miles per tank, but new methods will likely be needed for mass marketing.40

Forecasts regarding fuel cell vehicles range from complete failure to market dominance in decades. Our crystal ball is mildly sanguine. Fuel cell vehicles are immensely promising, but the challenge of getting started is daunting. Their success in the first few decades of the twenty-first century probably comes down to a decision by one or more automakers to take the plunge and lead the market. That company (or companies) must determine whether the benefits of being first are enough to offset large losses initially. Who will be first? Daimler-Benz took the first tentative step back in 1997. They were early leaders, with Ballard as a partner. But they had second thoughts and eased up. By 2007, four companies seemed about equal in capabilities and technology: Daimler, GM, Honda, and Toyota, with Nissan, Hyundai, and others trailing behind.

But it will take more than one or two aggressive car companies. They can't do it alone. It will take government intervention to prod or pay energy companies to provide fuel stations, and it will require strong incentives to attract early customers. Meanwhile, as this book goes to press, innovative start-up companies are dying, with Ballard itself giving up on the vehicle market and selling that part of the business to Ford and Daimler. As time goes on and governments embrace other options, especially biofuels and plug-in hybrids, automaker commitment to fuel cells and hydrogen wavers. The challenges of engaging government and energy suppliers in launching the hydrogen economy are giving them pause.

California created its "hydrogen highway" (more on this in chapter 7) and imposed zero-emission vehicle requirements, and the U.S. Department of Energy funded an initial fuel cell demonstration program in 2005-08. Still, much more commitment is needed, both symbolically and substantively. If significant intervention and support for alternative technologies doesn't materialize, autos will continue to use inherently inefficient combustion engines to burn fuels, be it conventional or unconventional oil or biofuels. Fuel cells and battery-powered vehicles are a new path, one that leads away from the problematic monoculture of internal combustion engine vehicles and petroleum fuels and that provides the potential for dramatic reductions in oil use and carbon emissions. But only with corporate and government leadership will this other path be followed in a timely fashion.

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