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Hydrogen Highway revisited

Is the plan by Arnold Schwarzenegger — and Gordon Campbell — for a hydrogen highway visionary, or just hot air?
California Governor Arnold Schwarzenegger fuels up at one of the state's 24 hydrogen stations.

By Matt Palmquist

High Country News

“Shakespeare said, ‘There is a tide in the affairs of men, which taken at the flood, leads on to fortune; but omitted, and all of life's voyage is bound in shallows and regrets,’” intoned Terry Tamminen, secretary of the California Environmental Protection Agency, when it was his turn at the podium on an overcast morning in April 2004. "We are afloat upon such a sea at this moment as we face our energy future. But who has the strength to lift our ship of state on a tide of clean, renewable energy that will carry our economy into the 21st century and beyond? Who has the wisdom to set us on course to protect our air, water, public health, and the health of our economy?

"Who has the vision to set sail towards our energy independence now?" Tamminen's answer, as Shakespeare could not have predicted, was Arnold Schwarzenegger. The last-action-hero-turned-Republican governor, who had won the recall election against Gray Davis the previous October, was still in the honeymoon phase of his first term when he addressed the large crowd of educators, automotive and energy executives and reporters at the University of California at Davis that day.

"As you can see, this looks kind of like a movie set here, right?" a beaming Schwarzenegger joked of the photo-op surroundings, which included a gleaming, sky-blue bus with a promise painted on it: "Zero Emissions — Cleans the Air As It Drives." Moments earlier he had drawn "oohs" and "aahs" when he pulled up to the fuel pump in a hydrogen-powered sports-utility vehicle.

"But of course it will be better," he said. "Because what you see here today, this is the future of California and the future of our environmental protection."

Schwarzenegger, heretofore synonymous in many environmentally attuned minds with his proud ownership of a fleet of huge, gas-guzzling Hummers, had come to Davis to announce Executive Order S-7-04, the establishment of a California Hydrogen Highway Network. By 2010, the governor vowed, every Californian would have access to hydrogen fuel along 21 of the state's interstate highways, "with a significant and increasing percentage of that hydrogen produced from clean, renewable sources."

Schwarzenegger's plan called for an initial 150 to 200 hydrogen-refueling plants throughout the state at an estimated cost of about $90 million, to be funded with corporate, state and federal money. By the end of the decade, Schwarzenegger said, he hoped to see 500,000 hydrogen-consuming vehicles zooming along California roads.

But as the governor made clear, his vision of progress was about both dollars and sense. "As I have said many times, the choice is not between economic progress and environmental protection," said Schwarzenegger, who, in topping off the SUV he'd arrived in, became the first person to use the inaugural station on his own Hydrogen Highway. "Here in California, growth and protecting our natural beauty go hand in hand. We have an opportunity to prove to the world that a thriving environment and economy can co-exist.

"This vision for California is real and attainable; however, it will take time. So, we must plant the seeds now."

24 stations, 200 vehicles

As of this summer, according to state officials, only 24 fueling stations on the Hydrogen Highway have been built, while another 15 sites have been identified for future development. None of these facilities looks very much like your corner gas station. In fact, they aren't open to the general public, in large part because no members of the general public are driving hydrogen-powered vehicles. Fewer than 200 hydrogen-fueled autos, buses or vans are actually driving on California's roads, and most of them are operated as "demonstration projects" by transportation agencies, city or state government fleets or automotive manufacturers.

Hydrogen has long been viewed as a potentially clean alternative to gasoline. In recent years, it has even been touted as the hypothetical basis of the future global economy, wherein the world's energy infrastructure would be transformed, with fuel-cell-powered cars and buildings all running on non-polluting hydrogen.

Hydrogen is plentiful in nature, it can theoretically be obtained in many ways, and fuel-cell vehicles have several potential advantages over gas-guzzlers: They are quiet, pump only water vapor out their tailpipes, and, if the electricity to make hydrogen is harnessed from clean sources, reduce transportation-related carbon emissions to near-zero. Accordingly, most major car companies have prototype hydrogen-powered cars in development, although they carry six-figure price tags and are nowhere near ready for widespread public use. As Tamminen put it: "It's a simple 'chicken or the egg' problem. Who will manufacture hydrogen cars without hydrogen fuel stations? Who will build hydrogen fuel stations if there are no vehicles to use them?"

In truth, though, hydrogen-car technology is years away from dropping an egg, much less hatching a chick. Obstacles include storage (hydrogen-powered cars require much larger tanks than gasoline-powered cars) and finding a pollution-free method to produce hydrogen. (At present, the most economical method uses natural gas and produces carbon dioxide.) Because of these and other logistical dilemmas, carmakers acknowledge that hydrogen-fueled vehicles won't hit showrooms for at least another decade and aren't likely to make a significant mainstream impact until mid-century — if then.

Moreover, skeptics of what they call "hydrogen hype" warn that by putting hydrogen at the centre of his environmental policy, Schwarzenegger is playing to energy and automotive companies and executives who have been major political funding sources. At the same time, the skeptics say, Schwarzenegger's green-sounding pro-hydrogen policies discourage the development of more immediately feasible alternatives, including already-established gasoline-electric hybrid technology that greatly increases auto efficiency and greatly reduces auto emissions. The idea of a "hydrogen economy" is a dangerous distraction, they say, created by automakers who should instead be taking urgent measures to cut the greenhouse gas emissions of their current lines of cars and trucks, which account for one-third of all U.S. carbon dioxide emissions.

"A hydrogen car is one of the least-efficient, most-expensive ways to reduce greenhouse gases," says Joseph Romm, who formerly oversaw U.S. Department of Energy's hydrogen fuel-cell research and now advises businesses on energy use and greenhouse emissions. "If you want to slow down global warming, you're not going to do it with a hydrogen car."

Chemical elements

Hydrogen is the lightest and most bountiful of the chemical elements, comprising 75 per cent of the universe's elemental mass. Composed of one proton and one electron, it bonds with other elements to form water (an H2O molecule consists of two hydrogen atoms bonded to an oxygen atom) and fossil fuels, including natural gas. But to be used as fuel, hydrogen has to be produced in pure form by unloosing the chemical bonds that bind it inside these other substances. Paradoxically, breaking those bonds to access hydrogen's energy is a process that in itself requires a great deal of energy. Most plans to power cars by burning hydrogen in internal combustion engines have fallen by the wayside because those engines would require very large on-board storage systems. Even when put under the pressure necessary to liquefy it, hydrogen is much less dense than gasoline; it therefore requires a large (and potentially explosive) storage tank, effectively reducing the driving range of the vehicle and increasing its cost.

And the environmental benefits of driving an expensive, internal-combustion hydrogen car are small, and perhaps even nonexistent. Many experts argue that running an internal combustion engine on hydrogen produced from natural gas creates as many greenhouse gas emissions as a standard, gasoline-burning car (and is far less efficient than gasoline-electric hybrids). Although some auto manufacturers, notably BMW, have produced hydrogen-burning cars, most of the auto-hydrogen focus is now on the stable, quiet and environmentally efficient fuel cell.

The first fuel cell — and the first hint that hydrogen could serve as an energy carrier — was stumbled upon in 1839, when a Welsh scientist was experimenting with electrolysis, the process wherein an electric charge and a catalyst are used to split water into its component parts, hydrogen and oxygen. Reversing the process, Sir William Robert Grove found that combining oxygen and hydrogen produced electricity and water. He dubbed his invention the "gaseous voltaic battery."

The modern fuel cell was developed in the early 1960s by General Electric for use in the Gemini space program. These early fuel cells were expensive and cumbersome; they required very pure hydrogen and oxygen, expensive platinum catalysts to speed up the hydrogen-oxygen reaction, and high operating temperatures. Because of these obstacles, fuel cells were used almost exclusively in space expeditions, where price was little or no object; only when lower-priced catalysts became available in the 1980s and ’90s were fuel cells viewed as potentially viable in earthbound modes of transportation. In fact, until the turn of the millennium, hydrogen was viewed as too volatile, too difficult to store, and too expensive to be trusted for widespread energy needs.

There are also the environmental problems associated with making hydrogen. Although proponents hope to eventually separate large amounts of it from coal or water, the most common method of producing hydrogen today is by "reforming" natural gas (for example, methane, propane, or ethane). The gas is combined with very hot steam (in the 700 to 1,000 degree Celsius range) in a reforming unit, where a catalytic reaction helps to break the bonds of the natural gas. This process creates reformate steam, which is composed mostly of hydrogen and carbon monoxide. In the next step — a shift reaction — the carbon monoxide in the gaseous mixture reacts with slightly lower-temperature steam, producing more hydrogen and some carbon dioxide. This unwanted carbon dioxide is then removed from the mixture in a process that produces pure hydrogen. All the other gas, save for the carbon dioxide, returns to the reformer, where it is combusted.

The carbon dioxide produced when natural gas is reformed could eventually be sequestered — underground, perhaps — so that it would not enter the Earth's atmosphere. But effective and economical technology for achieving sequestration is, by most accounts, a long ways off.

In 2003, as the U.S. Department of Energy's Fuel Cell Report to Congress predicted that "market forces alone are unlikely to result in large-scale use of fuel cells in the next few decades," President George W. Bush reached a different conclusion. In his State of the Union address that year, Bush announced a Hydrogen Fuel Initiative, pledging $1.7 billion over the next five years "to reverse America's growing dependence on foreign oil by accelerating the commercialization of hydrogen-powered fuel cells to power cars, trucks, homes and businesses with no pollution or greenhouse gases." The president's initiative was widely criticized as a dodge that merely delayed coming to grips with both global warming and energy dependency.

Government initiatives

It was against this backdrop — and with the promise of federal grants from the Department of Energy — that Schwarzenegger announced his Hydrogen Highway in 2004. California had long been working on hydrogen transportation initiatives, and support has been bipartisan; the West Sacramento-based California Fuel Cell Partnership, launched in 1999 by Democratic then-Gov. Gray Davis, includes more than 30 of the nation's leading auto and energy companies. "California has always been the most progressive state in the whole alternative energy scheme," says Roy Kim, a spokesman for the Fuel Cell Partnership. "We have an aggressive agenda in California, and we're trying to take the lead on hydrogen, too."

Schwarzenegger's ties with the auto industry, which supports the Fuel Cell Partnership and is one of his largest big-business sources of political funding, go way back; he would raise more than $1 million in campaign contributions from auto dealers and manufacturers during his first year as governor. (The anti-Schwarzenegger advocacy group claims he and his various political committees have accepted on the order of $6 million in total donations from the energy and automotive sectors.) Schwarzenegger had bought the first Hummer manufactured for civilian use in 1992, a truck so large that U.S. fuel economy regulations didn't apply to it. But he had adopted a decidedly pro-hydrogen stance during the gubernatorial recall campaign, when he announced that he would convert one of his Hummers to burn hydrogen — a bit of mechanic work that cost a reported $21,000.

During his time in office, Schwarzenegger has cultivated a growing reputation as the green governor (even adopting the color as the official hue of his re-election campaign). He has guest-starred on the Earth Day edition of MTV's Pimp My Ride, championing clean-energy automobiles, and Newsweek put him on the cover for his environmental achievements. Those include signing an executive order requiring the state to slash its greenhouse gas emissions 80 per cent below 1990 levels by mid-century, along with his backing of a clean-car bill, opposed by many automotive companies, mandating that California's new cars and light trucks spew fewer pollutants by 2009.

On the other hand, his latest proposed budget calls for $1 billion in gasoline tax revenues to be directed away from mass transit, and he has cut funding for a long-planned and environmentally friendly bullet train that would carry passengers from Los Angeles to San Francisco in two hours. And in June, he abruptly fired the chairman of the California Air Resources Board, sparking a debate about whether the governor's administration was trying to stall emissions reforms.

Still, environmental groups have generally praised the governor for making global warming a topic of discussion, even if he insists it can be solved by technology rather than changes in lifestyle. David Hawkins, climate director for the Natural Resources Defense Council, told Rolling Stone that Schwarzenegger "belongs in the sparsely populated top tier of elected officials who are not only taking global warming seriously but devising solutions on a scale that actually matches the problem."

Schwarzenegger has found other politicians willing to embrace his dream. In British Columbia, Premier Gordon Campbell is forging ahead with plans to construct an $89-million Hydrogen Highway to stretch between Vancouver and Whistler — if all goes well, in time for the 2010 Winter Olympics. The province has $45 million in federal funding earmarked to begin building 20 hydrogen-fueled buses and the first of the province's fueling stations. In March of this year, Campbell and Schwarzenegger discussed linking the two systems through Washington and Oregon, but there are no concrete plans yet to do so. "I think what this Hydrogen Highway does is create a totally benign means of transportation in terms of emissions," Campbell told Canadian reporters.

Not to be outdone, Florida Gov. Jeb Bush, R, broke ground in 2005 on the first hydrogen fueling station in Florida, with hopes to link Orlando and Tampa via a Hydrogen Highway.

Real life example

If you want to see the world's most comprehensive and pragmatic demonstration of hydrogen's potential as a fuel solution, you have to go to the back corner of a bus depot in Oakland, Calif. Not an upscale locale, it's on the fringes of an industrial sector where wind, rumbling BART trains and low-flying airplanes frequently drown out conversation. Because of safety concerns and space constraints, the eight-year-old operation is confined to a cluster of low buildings encircled by a high brick wall, a fair distance from the hangars and fuel bays serving ordinary gas-guzzling buses. Only a few design conceits, like the bright blue and yellow fueling pump with a Jetsons-esque roof, hint that hydrogen is flowing out of these nozzles.

It is a substation of AC Transit, a regional bus agency that serves the eastern part of the Bay Area and a few routes that cross the Bay Bridge into San Francisco. Since the turn of the millennium, AC Transit has been, in the words of Democratic Congresswoman Ellen Tauscher, "leading the way as a national model for success in implementing alternative energy sources." The agency operates three zero-emission, hydrogen fuel cell, hybrid-electric buses (with electrical energy generated and stored whenever the brakes are applied), and it has plans to roll out several more in the near future. It also owns a fleet of 10 fuel-cell cars manufactured by Hyundai and Kia. As part of the Hydrogen Highway, the substation gets most of its funding from the state, but has also developed partnerships with numerous energy and automotive companies. More than 100,000 passengers have ridden on one of AC Transit's hydrogen buses. And even the flashlights in use at the substation run on hydrogen stored in the handle; the 1-watt LED shines for 24 hours on a single charge.

But what really sets the operation apart is its energy station, which reforms natural gas into hydrogen on-site, thereby avoiding the leaks, waste or accidents that might occur when hydrogen is transported to a fueling facility. The station pumps out 150 kilograms of hydrogen per day, enough to fuel the three 40-foot-long fuel-cell buses in the fleet, and can keep 366 kilograms in its storage tanks. The role of oil companies in this burgeoning technology could not be more obvious: Chevron decals are plastered on walls and equipment, and Chevron runs all of the substation's computer systems from its Houston headquarters.

"Watch your step," says a genial, silver-haired technician, as he leads me into the cramped confines of what he calls a "mini-refinery," a labyrinth of humming metallic tanks and generators. A bronze pipe pumps in natural gas at one end of the room, delivered from the local utility company; this gas is then delivered into two metallic boxes, the steam methane reformers, where high-temperature steam begins to break the bonds of the natural gas. The output, called reformate steam, typically consists of 75 per cent hydrogen and 20 per cent carbon dioxide, with the remainder being made up of trace gases, including carbon monoxide and methane. This mixture is then compressed to 125 pounds per square inch, the pressure required to separate hydrogen from impurities in the gas stream. The reformate enters a purification unit that produces 99.999 per cent pure hydrogen. Huge tanks with closely monitored valves store the hydrogen on-site, until one of the three buses pulls up to the filling station.

At that point, a technician who has completed the requisite safety training waves a wand-like sensor over and around the bus's fuel tank, checking for any possible hydrogen leaks. (Only one employee has suffered an injury working near the fuel-cell buses; he accidentally sliced his finger.) "We can't afford a mistake," says Jaimie Levin, the agency's director of marketing, as he watches the bus being refueled. "Hydrogen is expansive and explosive."

It takes about 15 minutes to fuel one of the buses, whose ceilings contain eight hydrogen tanks that are closely monitored by the internal computer systems on the bus; should the vehicle lose power for any reason, valves snap shut to cut off the flow of hydrogen. The fuel-cell power plant is housed in the rear of the bus, below a cooling system that keeps it near ambient temperature; it receives the flow of hydrogen from the tanks above, then converts the hydrogen into the electricity that powers electric motors that power the vehicle.

Levin, who has wiry gray hair and a breathless enthusiasm for hydrogen's potential, once pitched President Bush on the agency's program during the president's visit to the California Fuel Cell Partnership; at the time, Bush was standing on the steps of an AC Transit bus. And Levin is adamant that public transportation agencies should be at the forefront of practical applications of hydrogen technology. "The value of hydrogen is that we can make significant impacts in the most densely populated areas of the world," Levin said. "More people should be taking public transportation, and we should be giving them an array of clean-energy options."

There is still no certainty as to the form of hydrogen that would eventually be used if the element became the basis of a global economy, in large part because of hydrogen's volatile nature and the difficulties involved in storing it. Hydrogen takes up more space than any other fuel, whether in a gaseous or liquid state. Hydrogen is also highly flammable, and its reputation has suffered — perhaps disproportionately — as a result of the Hindenburg disaster.

The largest zeppelin ever built, the Hindenburg was kept aloft by large hydrogen-filled bags. In May of 1937, the zeppelin burst into flames while arriving in New Jersey during an electrical storm; it crashed to the ground 30 seconds later, killing 36, nearly all of whom jumped or fell to their death. The seminal event, captured on newsreel footage and still synonymous in many people's minds with hydrogen, is at odds with hydrogen's generally safe industrial record. Today, most investigators believe hydrogen was not the cause of the fire, although it certainly fed the flames rising above the zeppelin as it went down.

In several different crash and safety studies, hydrogen has been shown to burn much differently than gasoline, which erupts in all directions; because hydrogen is so light, a single clear flame burns high into the air, while much of the element escapes before it can catch fire. Hydrogen also requires a much higher ignition temperature than gasoline does, and its theoretical explosive power per unit volume of gas is 22 times weaker than that of gasoline vapor.

Optimistic projections

In the wake of President Bush's 2003 State of the Union address, a panel of experts was convened by the National Academy of Sciences to guide research programs and set priorities for hydrogen development at the U.S. Department of Energy. The panel, which included representatives from oil companies, carmakers, environmental groups and universities, studied what it called "optimistic" projections based on how quickly motorists are embracing the gas-electric hybrids currently on the market, a much easier transition than the switch to hydrogen. After a year of study, the panel concluded that hydrogen could fundamentally transform the U.S. energy system but "does not represent a short-term solution to any of the nation's energy problems."

Even if the first hydrogen cars were rolled out in mass production in 2015, the panel said, they still would claim only a 25 per cent share of the market by 2027. Production of hydrogen for transportation would be about 9 million tons a year by then, which is just 8 per cent of the 110 million tons required to fuel a complete shift from gasoline to hydrogen nationwide. As Michael Ramage, chair of the academy panel and a former executive vice president for technology programs at ExxonMobil, put it: "Even if the cars are introduced in 2015, which is the president's vision, to get those cars into the market, and the infrastructure built, is a long process." On the other hand, the Academy report noted, "Hybrid electric vehicle technology is commercially available today, and benefits from this technology can therefore be utilized immediately," pointing to high-mileage hybrid electric vehicles such as the Toyota Prius and Honda Civic Hybrid.

In California, criticism of Schwarzenegger's Hydrogen Highway has run in a similar vein. The Reason Foundation, a libertarian think tank, released a report concluding that "while hydrogen itself may be clean-burning, the processes used to manufacture and distribute hydrogen are dirty enough to nearly negate the benefits — and the cost of conversion isn't worth the difference." The study's project director, Adrian Moore, said, "Until we figure out ways to create hydrogen that are less energy-intensive or the performance of hydrogen improves, it's not a good air-quality measure."

Though state environmental officials acknowledge the merits of those arguments, they point out that hydrogen is an emerging technology, and so cost-lowering advances could be rapid. "Where we're standing right now, there's a small demand for hydrogen fuel," says Kim of the California Fuel Cell Partnership. "You've got to understand that the state of the fuel is pretty limited. We're not at a commercial state just yet with the hydrogen fuel cell."

As a result, state officials have had to adjust Schwarzenegger's initial plan for the Hydrogen Highway, although they say it remains a priority of the governor's environmental policy. Fueling stations are no longer planned at 20-mile increments along the state's major freeways; the initiative is now targeting clusters around major cities — which could also mean more of a focus on municipal or public transportation fleets. This first phase of the plan, expected to be completed by 2010, will require about $53 million in state funds, with an additional $32.5 million contributed by energy companies for the construction of refueling stations.

"Right now the plan is to focus on urban clusters and eventually, hopefully, connect them along the way," Kim says. "With the 24 stations in operation, no two are alike. We're really still in the demonstration phase, trying to figure out, 'What's the best approach to this?'"

Environmental groups have largely hailed the idea of the Hydrogen Highway, although they advocate the production of hydrogen from renewable sources, such as solar, hydro, wind, and biomass, as opposed to natural gas. As Carl Pope, executive director of the Sierra Club, put it: "The promise of hydrogen is making it from the sun. The risk of hydrogen is making it from coal." Roland Hwang, vehicle policy director for the Natural Resources Defense Council in San Francisco, called the plan "a reasonable first step. California is saying if we help put the stations in, we're expecting Detroit to provide the vehicles.''

But Joseph Romm, who helped oversee hydrogen and transportation fuel cell research in the Department of Energy during the Clinton administration, has led the chorus of hydrogen naysayers. In 2003, Romm, a physicist, published a book, The Hype About Hydrogen, that has become the rallying cry for those who oppose initiatives like Schwarzenegger's highway. Romm says he thinks the focus on major cities is a better idea than the original Hydrogen Highway proposal, but is still concerned that the public believes hydrogen to be a fully "green" technology, while in the short term it will most likely be produced by using fossil fuels.

With current technology, natural gas provides the least expensive and most practical method of producing large amounts of hydrogen; in fact, steam reformation accounts for about 80 per cent of the world's current hydrogen production, in large part because of the existing natural gas infrastructure. Proponents argue that cracking water could someday produce hydrogen, but huge amounts of electricity are required during the electrolysis process that separates hydrogen from water. In fact, electrolysis is one of the most energy-consuming methods of producing hydrogen. If the electricity required to power electrolysis comes from "dirty" sources — coal, oil, or natural gas — the resulting greenhouse gas emissions are high compared to other production methods, including natural gas reforming, which require less energy on the front end.

Some hydrogen backers, including President Bush, hope that coal gasification — wherein gasified coal is treated with steam and oxygen, forming hydrogen gas, carbon monoxide and carbon dioxide — could produce bulk hydrogen in the future. But it's almost twice as expensive to produce hydrogen from coal as from natural gas, and the process produces significant amounts of carbon dioxide and other pollutants, including sulfur.

Earlier this year, another panel was convened in Washington, this one tasked with reviewing the progress made on the president's hydrogen initiative since it was announced four years ago. Ben Knight, a vice president of Honda Motor Corp., which is building a prototype hydrogen car, called it "the most challenging technology the auto industry has ever done."

Phillip Baxley, the president of Shell Hydrogen, which has opened several of the stations equipped to handle hydrogen cars in the Los Angeles area, said his company was now hoping that the first small-scale rollout of hydrogen vehicles would begin by 2025. "It may be a long time before it happens," he said. Romm is even less optimistic. He said he thinks hydrogen cars will be broadly available to the general public "not in our lifetime, and very possibly never."

On the bus

The most advanced hydrogen fuel-cell bus in the world is as quiet as a golf cart. And it doesn't smell like a conventional bus, because there are no gasoline fumes. "Go ahead and floor it," says a technician with UTC Systems, maker of the fuel cell that powers the vehicle. He grabs onto a support pole while I take a quick spin around the AC Transit substation. "Just keep spinning the wheel until you can't anymore," he says.

It's a quick journey, and the impressive turning radius of the 9,000-pound, $3.2 million bus makes it even quicker. Just fueled up with hydrogen, the bus is about to go back on to the streets of East Oakland. Five more hydrogen-powered fuel-cell buses are planned for the coming years, to be built by the pioneering Belgian contractor Van Hool NV, which has also begun introducing prototypes in Europe.

"I know the arguments that Joe Romm makes," says Levin, the hydrogen advocate, after the bus has rolled to a stop. Standing next to the vehicle, gesturing to the corporate logos and state agency decals plastered on its sides, Levin gives a rueful smile. "Look, Chevron is a big oil company, and that's an emotional issue. Clearly there's a PR value for them, but it could also be a big part of their future. You could accuse other companies of just waiting to see how it all turns out," Levin says. "At the end of the day, 100,000 people in East Oakland have experienced a hydrogen-powered bus, with no fumes and no noise."

No members of the public have requested to use the substation to fill up their hydrogen-powered cars, Levin says, and he admits that the very idea isn't practical because of the safety, permitting and technical issues associated with current hydrogen technology. When asked what role his fueling station plays on the Hydrogen Highway, Levin chortles.

"If there's going to be a highway, it's going to start with fleet applications like ours," he says, slipping off his black sunglasses, toying with them in his hands. "Do you have a hydrogen car? Will you in five years?" And then he puts his shades back on and says, "It's not a silver bullet."

The author writes from San Francisco.