Soon after Gov. Arnold Schwarzenegger (R) took office in 2003, he set in motion a campaign promise to build, by 2010, a "hydrogen highway" composed of 150 to 200 fueling stations spaced every 20 miles along California's major highways.

Schwarzenegger's "Vision 2010" plan promised that every California motorist would have access to hydrogen fuel by the end of the decade. He has since repeatedly mentioned the highway in a standard stump speech on his environmental accomplishments.

But the program has fallen short of expectations. With less than 10 months until the end of the decade, only 24 hydrogen fueling stations are operating in California, most of them near Los Angeles.

The vision of a hydrogen infrastructure, with fueling stations dotting the interstates, has not materialized, partly because the eager governor may have set unrealistic targets.

Gerhard Achtelik, manager of the hydrogen highway program at the Air Resources Board, admitted in an interview that the state would not hit its 150-station goal by 2010.

"That was a very optimistic guess," Achtelik said. "It's certainly been a learning experience."

The state's hydrogen-highway experience points to a fundamental question confronting any effort to build an alternative car market, be it powered by hydrogen or electricity: What comes first, the vehicle or the infrastructure?

Of the hydrogen effort, Achtelik conceded that the public has "not received the vehicles as quickly as we hoped."

Automakers have developed test models and advanced fuel-cell technology in labs around the world, but this test phase has not yet resulted in anything close to a commercial hydrogen car market.

"If all the cars were there that would be needed for the infrastructure, then the stations would be there," Achtelik said.

Vision with 'hiccups'

Roy Kim, of the California Fuel Cell Partnership, also said developing hydrogen stations when there are not enough cars to serve them does not make sense. The most likely candidates to build the stations in the private sector -- the oil companies -- still see the infrastructure as a questionable investment, while public dollars, especially in cash-strapped California, have been scarce.

But Kim sees reason for optimism, with General Motors Corp., Honda Motor Co., Toyota Motor Corp. and Daimler AG moving closer to putting hydrogen cars in the hands of customers. Once the Honda Clarity or GM Equinox catches on, the stations will come, he argued.

"It has had its hiccups," said Kim of the hydrogen highway program. "But this is characteristic of any emerging new technology. It takes time to realize a vision, and it takes patience to get there."

Kim compares the hydrogen fuel cell to the personal computer and likes to reference Microsoft Corp. founder Bill Gates' famous prediction that he would one day see a personal computer in every household. Hydrogen fuel cells are getting slimmer and safer, he said, and commercial pilot projects have shown promise.

Catherine Rips, managing director of the California Hydrogen Business Council, puts it another way. She said the alternative car market in the United States – with hydrogen matching up against plug-in electrics, hybrids and biodiesels, to name a few – has spread itself outward rather than imitating the internal combustion engine's more linear path. This means the highway concept, which was adopted early in the decade, may not apply, at least for the time being.

"What sounded like a good idea in 1999 doesn't necessarily match up with reality a decade later," Rips said. "New technology doesn't follow a straight path."

Joan Ogden, director of the Sustainable Transportation Energy Pathways program at the University of California, Davis, says the 150-station idea was a "broad-brush vision" that experts quickly realized was unlikely to be fulfilled after the governor launched his program.

Transportation planners and policymakers, Ogden said, several years ago stopped taking the highway concept literally. They came up with a new image – the cluster – and decided a more doable pilot program would be to create a network of 10 to 20 stations in a specific region, to fuel the cars where they reside.

Shell Hydrogen BV, an industry leader, and GM soon advocated the same concept in a study that called for the creation of station clusters in three locations, including Los Angeles. So now you have, in theory, a developing network in a region where automakers can directly market their cars.

"GM has repeatedly said the development of such a cluster is what is needed to take their learning to the next level," Rips said.

Zero-emissions rule

Crucial to the emergence of the cluster, in Ogden's view, is California's zero-emissions vehicle rule, which goes into effect in 2012. Under the regulation, which was advanced by the state's Air Resources Board, automakers will be required to make 7,500 "pure ZEVs" in the 2012-14 time frame, and 25,000 in 2015-17.

Because pure ZEVs emit no greenhouse gas emissions from their tailpipes, that means fuel-cell cars powered by either hydrogen or electricity. "I'm actually pretty encouraged," Ogden said. "When I started watching this 15 years ago, it took the whole back of a minivan to hold a fuel system. You have a very attractive car now."

The market for the vehicles and the infrastructure, Ogden added, should "really be driven by this ZEV regulation." The automakers have announced plans to introduce hundreds of fuel-cell vehicles into Southern California in the years ahead, in hopes that a cluster would emerge.

"Clusters make a lot more sense at this point," agreed Achtelik, who predicted "bridge stations" to Las Vegas and Santa Barbara, Calif., from the Los Angeles region by 2014 or 2015.

But just who will build the fueling stations beyond the experimental stage is still an open question.

Ogden said the oil companies, unlike the carmakers, are not regulated to build the infrastructure or participate in the fledgling market. Shell Hydrogen and Chevron Corp. are involved in demonstration stations, but they have been resistant to all-out investment for a reason.

"There's some question as to how this is going to take place," Ogden said. "What we really need is a network demo."

'It's in the mix'

To the automakers, the bumps on the hydrogen highway are emblematic of the state of the alternative car market and the difficulties associated with building cars during the economic downturn.

The manufacturers are developing a number of models to meet increasing fuel economy standards, with an eye on greenhouse gas emissions reduction policies like the one adopted in California under A.B. 32. That means flex-fuel, compressed natural gas and biodiesel vehicles in addition to hydrogen and electric fuel cells.

What are lacking, said Charles Territo, spokesman for the Alliance of Automobile Manufacturers, are clear signals on stations and how drivers will be able to drive long distances. "Our industry is committed to offering the vehicles," he said, "but the reality is there needs to be a very significant effort to expand the alternative fuel infrastructure."

Ultimately, Territo added, consumers will likely decide on a region-by-region basis what technology they prefer. Some regions in the Midwest could see ethanol-85 networks emerge, while more urban areas could see electrification.

And hydrogen? "It's in the mix," Territo said. "Our goal as manufacturers is to provide as many different technologies as possible."

In the short term, hydrogen advocates have applauded the federal stimulus package, which has billions set aside for research into fuel cells and $300 million earmarked specifically for alt-vehicle infrastructure projects. In the long term, they would like to see more public dollars to build the stations, possibly alongside state and federal facilities in highway rest stops.

"There's not yet a commercial case for an infrastructure provider," Rips said. "It's going to take public support, or a mandate."

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