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BY THOMAS K. GROSE
Illustration by John Sledd

Photo: Spiral staircase inside London City Hall

HYPE OR HOPE?

A once favored alternative fuel is shunted to the slow lane.


Bruce Logan, director of the Hydrogen Energy Center at Pennsylvania State University, sounds exasperated, if not angry: "It's a completely puzzling decision. To me, it makes no sense." The source of Logan's irritation? The Obama administration's recent moves to throttle back on hydrogen and fuel cell research, while greatly increasing spending on development of electric vehicles and batteries. Logan is one of many researchers who have labored for years to make hydrogen fuel cell vehicles a viable reality. He still sees it as the superior option for replacing petroleum-based vehicles. Nevertheless, hydrogen is now stuck in the research slow lane. Many academics have jumped from hydrogen to batteries. "You follow the money," Logan says.

For much of the past decade, the research money trail led to hydrogen and fuel cells, technologies that were the great green hope to replace internal-combustion engines as the transportation power plant of choice worldwide. It's easy to see why. Hydrogen is the most abundant element there is, it's clean, and we'll never run out of it. Mix it with oxygen in a fuel cell, and the resulting chemical reaction produces electricity. The process's only emission: a trickle of water. And its source is here, not in the Middle East or Venezuela.

But the Obama White House decided early on that those efforts would take too long to reach commercial fruition in a world that urgently needs to reduce consumption of fossil fuels, which emit the greenhouse gases that greatly contribute to global warming. Energy Secretary Steven Chu and his top lieutenants now argue that a big push to get more electric vehicles and plug-in hybrids on the road is the surest way for America to begin pulling away from dependence on foreign oil.

Automakers Make the Switch

Meanwhile, the automotive industry has rallied behind electrics, as well. By the end of this year, both Nissan and General Motors will start selling electric models: Nissan is introducing the Leaf, an all-electric car with a range of 100 miles that can recharge in eight hours; GM's launching the Chevrolet Volt, a plug-in hybrid that can cover 40 miles before its backup gasoline motor kicks in to increase its range. Most other major carmakers say they'll also soon have an offering of electrics or plug-ins in their showrooms, and none is currently touting hydrogen. Indeed, an Audi spokesman tells Prism that the company can't talk about hydrogen now because "it's too far in the future."

 So, is it the end of the road for hydrogen fuel-cell cars? It might be, except that, as Chao-Yang Wang points out, federal alternative fuel policies have long been "very fickle." Wang, who heads the Electrochemical Engine Center at Penn State, has redirected his center's research efforts from hydrogen to batteries. Such switches underscore a point made earlier this year by David Friedman, a senior engineer and research director with the Union of Concerned Scientists, before the Senate Energy and Natural Resources Committee. Policy shifts over the past 40 years, variously favoring batteries, several synthetic fuels, and fuel cells, mean that each has "suffered for our lack of a comprehensive, long-term policy."

No Certainty on Fuels

The only thing beyond dispute is that there is no clear picture of what will ultimately supersede gasoline-powered cars. "People want certainty when it comes to fuels, but there is no such thing right now," and that includes hydrogen, explains John Heywood, director of the Sloan Automotive Laboratory at the Massachusetts Institute of Technology.

Many problems with hydrogen and fuel-cell technologies are not quite solved, including fuel-cell durability, hydrogen production, and storage of the volatile, lightweight gas. There's also no existing hydrogen distribution infrastructure, and it would be monumentally difficult to get millions of fuel-cell cars on the road while simultaneously building a distribution network to support them. Says Wang: "Infrastructure is a huge hurdle to acceptance."

Energy Secretary Chu told Technology Review last year: "In order to get significant deployment, you need four significant technological breakthroughs. . . . If you need four miracles, that's unlikely: Saints only need three miracles." In Senate testimony earlier this year, David Sandalow, an assistant energy secretary, said, ". . . We need to focus in on those [technologies] that have extraordinarily high potential, and that, in my opinion, is electric drive."

Wang estimates that it will take at least another five years to make hydrogen technologies consumer-ready. Right now they're very expensive. Toyota says it expects to sell a fuel-cell car by 2015 for around $50,000, but Scott Grasman, an associate professor of systems engineering at the Missouri University of Science and Technology, says the cost of one today would be at least double that amount. Meanwhile, the Nissan Leaf's base price will be $32,780, dropping to $25,280 with a federal tax credit.

Hydrogen: Not So Green

As complications mount, the task of solving hydrogen's problems in time to make an impact on climate change begins to "look like a tall order," explains Giorgio Rizzoni, director of the Center for Automotive Research at Ohio State University. Garel Rhys, a professor emeritus of automotive economics at the Cardiff University Business School, agrees: "Hydrogen is still very much science fiction in practical terms."

What's more, as Rizzoni notes, "hydrogen right now is not as clean as it sounds." Despite its ubiquity, "it does not exist in free form." And hydrogen production is a dirty business. Most hydrogen used in the United States is produced from natural gas. It's separated out using a process called steam reforming, so there are emissions of greenhouse gases. It's also not an efficient process, says Jon Maddy, who runs the Hydrogen Research Unit at the University of Glamorgan in Wales. That's because there's a 20 percent energy loss in the process. "You might as well use natural gas in the first place." Researchers at Maddy's center are working on a process that would derive hydrogen directly from biomass, everything from sewage sludge to food waste. It's a great idea, but again, it's not quite ready for prime time.

Grasman admits that "the technology for EVs is more advanced; it's easier to quickly get EVs on the road." For one thing, many buyers will be able to charge plug-in vehicles at home or in an office parking lot. Still, electric vehicles also present some daunting problems. Long-distance driving will require access to charging or battery replacement stations. A national network of these will be complicated and expensive to build. The University of California, Berkeley, estimates that it will cost $320 billion over several decades. And it will probably need a fair amount of government incentives and investment.

Battery-powered electric cars have other problems to surmount, as well. Rapid charging technology - a must, since most drivers won't always have eight hours to spare - is not yet readily available. Moreover, battery storage capacity, despite herculean efforts, can't as yet accommodate affordable cars that can go much beyond 100 miles. "I continue to see a problem with range anxiety with batteries," says South Carolina's Van Zee.

Electrics are also at the mercy of an electric power industry that's far from clean. Around 85 percent of America's electricity comes from fossil fuels, half coming from coal. So, although electric cars don't emit greenhouse gases, their batteries are charged by electricity that comes from power stations that do.

Research Council: Don't Give Up

What often gets lost in the debate over hydrogen fuel cells and battery technology is that both are used to power electric motors. If you yank the batteries from an electric car and replace them with a stack of fuel cells, or vice versa, the drive train remains electric. That's why hydrogen proponents are convinced that electrics and plug-ins are merely short-term technologies, a means to kickstart the effort to replace gasoline cars and buy time until hydrogen fuel cells are commercially viable. "If you listen to the car companies," Van Zee says, "they're saying that fuel-cell vehicles are the long-term solution."

So is it shortsighted to cut back so sharply on the research, since that will only further delay a transition to hydrogen? That's the thrust of a report issued last June by the National Research Council. While admitting that hydrogen fuel cell research had not yet hit performance or cost goals, the report said that efforts to replace gasoline-powered vehicles should continue to include fuel cells and hydrogen because of the environmental advantages. Vernon P. Roan, who headed the committee that wrote the report, stressed the need "to perform the type of high-risk research in areas such as hydrogen that would not be otherwise taken on by the private sector."

There is, however, a problem with the theory that electrics and plug-ins are mere bridge technologies. After spending hundreds of billions of dollars on building a charging infrastructure to accommodate electrics, how willing will consumers and policymakers be to spend many billions more on yet another complex infrastructure for hydrogen? Says Rhys: "That is a killer." Moreover, Grasman says, "battery technology is getting pretty good." He thinks affordable electric cars capable of driving 300 miles are a distinct possibility.

If there are breakthroughs in battery storage capacity over the next few years, and if renewable sources of energy, including solar and wind, begin to account for a greater share of the world's power generation, there may be no reason to move beyond battery-powered electric vehicle technology. Those are very big ifs, Rhys admits, but he nevertheless adds: "It is possible that a move to hydrogen will never occur."


Thomas K. Grose is Prism's chief correspondent, based in the United Kingdom.

 

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