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Only movie stars and select consumers have been able to get their hands on hydrogen fuel cell vehicles in the United States over the past few years, but now these zero-emissions cars are poised to bust onto the scene in a big way around 2015 to 2017.

A limited number of fuel cell electric vehicles (FCEVs) are available for lease today, and nearly all of them in California, where refueling stations are slowly cropping up.

Earlier this year, model-turned-actress Diane Kruger was spotted in the Mercedes-Benz F-Cell, the company's compact fuel cell car with a combined U.S. EPA rating of 52 mpg and a range of 190 miles per tank of hydrogen.

Actress Jamie Lee Curtis, another famous early adopter, has been seen driving the Honda Motor Co. FCX Clarity, which has an EPA rating of 60 mpg and 240-mile range.

EPA considered hydrogen fuel cell vehicles "game-changing" in reducing greenhouse gas emissions in the new federal fuel economy standards, which require light-duty vehicles to reach a fleet average rating of 54.5 mpg by 2025. The agency included credits for automakers to build FCEVs in the regulation in hopes of accelerating their debut on the market.

California has been leading the way on the road to higher fuel economy. State regulations are pushing for 15 percent of the fleet to be zero-emissions vehicles by 2025. And by 2050, the California Air Resources Board projects that most vehicles in the state could run on hydrogen.

FCEVs enjoy many of the benefits of electric drive: They're quiet, handle well and have no tailpipe emissions. Unlike plug-in cars, they aren't limited by size, range or long recharging times. Drivers simply fill up on hydrogen -- where it's available -- and go.

"A lot of focus is on plug-in vehicles because they're being sold today. And yet, from the state and a policy perspective and the automakers' perspective, they realize [electric vehicles] are going to have limited appeal," said Catherine Dunwoody, executive director of the California Fuel Cell Partnership, a public-private collaboration working to promote the commercialization of hydrogen fuel cell vehicles.

"They really do see the fuel cell vehicle as an all-electric, zero-emission vehicle that truly replaces the cars we drive today," she said.

50,000 cars in California in 5 years?
Although it's still a long shot, the idea that FCEVs could one day replace conventional gasoline cars seems more likely today than ever before.

Department of Energy research has helped drive down the cost of automotive fuel cells by 80 percent. Results of a national FCEV demonstration found that, although less than the range on a tank of gasoline, the range on a tank of hydrogen has consistently increased, and now thousands of cars are being prepared to hit the market.

After decades of testing, automakers are expected to put 50,000 hydrogen fuel cell vehicles on the roads in California by 2017, according to Dunwoody.

Mercedes has said it plans to release a mass-produced FCEV in 2014 and will launch a hydrogen-powered SUV or large sedan in the coming years. Honda global CEO Takanobu Ito said last week that Honda considers the FCEV "the ultimate environmentally responsible vehicle" and will launch an all-new fuel cell electric model in Japan, followed by the United States and Europe starting in 2015.

Jim Lentz, president and CEO of Toyota Motor Corp.'s U.S. division, said his company will also add a hydrogen fuel cell sedan to its lineup in 2015 (Greenwire, Aug. 15).

South Korean automaker Hyundai Motor Co. is "very, very bullish" on fuel cell vehicles, Hyundai Motor America CEO John Krafcik said at the 5th International Environmentally Friendly Vehicle Conference earlier this month, where the company featured its Tucson ix FCEV. Hyundai plans to make as many as 10,000 FCEVs by 2015.

General Motors Co. hasn't made any announcements but is looking to release a fuel cell option in the 2017 time frame, said Daniel Frakes, manager of vehicle, fuels and advanced technology policy for GM.

Ford Motor Co. has been working on FCEVs for 20 years and continues to research fuel cell stack technology in partnership with Daimler AG. But the company will add a fuel cell powertrain to its lineup only "when we can provide cost-competitive, high-value performance to our customers while, at the same time, making business sense to Ford," said Scott Staley, chief engineer of electrification research.

The Renault-Nissan Alliance is also building a hydrogen fuel cell vehicle in a strategic partnership with Daimler AG. Last year, Nissan announced it had joined with 12 other companies to launch FCEVs and develop hydrogen infrastructure in Japan. The company expects to offer an FCEV on the market in the next five years for around $50,000 to $60,000, according to Mark Perry, director of product planning and strategy at Nissan North America.

"But if you think EV [electric vehicle] infrastructure is tough, just wait for hydrogen," Perry said.

Where are the filling stations?
The United States will need a lot more fueling stations for both EVs and FCEVs before either option can be considered convenient. But at least the electric grid runs throughout the country. Hydrogen, by comparison, is much harder to find.

The California Air Resources Board plans to launch a network of 68 hydrogen stations by the end of 2015 to serve the burgeoning FCEV market. The state currently has nine public access stations, 14 private stations and another 14 that have been funded or are being developed, according to DOE's 2011 Fuel Cell Technologies Market Report.

According to Dunwoody, it will cost about $65 million to reach the 68-station mark. The difficulty is getting energy companies to pony up for the stations before the cars hit the roads.

The next challenge is getting hydrogen to the stations.

One option is to truck it in from centralized production facilities located primarily along the Gulf Coast, where hydrogen is used at oil refineries to desulfurize fuels. But the best and cheapest route to fueling the growing number of FCEVs may be to piggyback on the existing natural gas pipeline system that already crisscrosses the country, supplying about a quarter of U.S. energy.

Hydrogen can be made with no upstream emissions using renewable energy to separate hydrogen from a water molecule in a process called electrolysis. But most hydrogen today is made from natural gas, which brings the cost of hydrogen down closer to that of gasoline but makes the FCEV about 50 percent less carbon-intensive than a gasoline vehicle.

The U.S. shale boom has created what industry experts expect to be long-term, low and stable prices for natural gas. This transformation has put new life into the development of both dedicated natural gas vehicles and fuel cell cars.

"Prior to this, it was thought that we had to build stand-alone stations," said Edward Kiczek, global business director of Air Products and Chemicals Inc., a major hydrogen producer. "I think there's a realization of the need to take advantage of all existing infrastructure out there today to transition to a new fuel."

Compressed natural gas (CNG) passenger vehicles were granted incentives in EPA's greenhouse gas rule for model years 2017-2025 on the basis that they would help pave the way for the commercialization of FCEVs.

According to EPA, improvements to CNG vehicle fuel tanks could spell direct gains for hydrogen fuel tanks because they face the same challenges of safely and economically storing a gaseous fuel without limiting vehicle range. Enhancing the availability of CNG cars could also bring natural gas to more fueling stations, which could be converted to hydrogen on-site and help overcome FCEV's infrastructure speed bump.

An alliance with natural gas stations and cars?
But CNG vehicles for passenger use have their own hurdles to overcome. As with FCEVs, public fueling stations are few in number, the cars come at a premium and their fuel tanks are bulky and range-limiting (EnergyWire, July 20).

The Honda Civic Natural Gas is currently the only light-duty CNG model offered in the United States. It drives like a regular gasoline-powered car but produces 20 to 30 percent less greenhouse gas emissions than a gasoline or diesel car. Because of low natural gas prices, the Civic Natural Gas may also offer 30 to 40 percent fuel cost savings. But the fuel tank eats up most of the trunk space, and with a sticker price about $7,000 higher than a traditional Civic, the car would have to cover a lot of ground to recuperate the cost.

Honda will receive a small credit for producing CNG cars under the new fuel economy rules for 2017-2025 but in the meantime intends to keep production steady at around 2,000 to 3,000 at its plant in Greensburg, Ind.

To meet the 2025 target, the company is pushing all its technologies at once, including the Earth Dreams powertrain technology that improves the fuel economy of conventional gasoline vehicles by 10 percent.

"We're not betting the farm on any one technology. We're moving ahead with CNG, fuel cells, plug-in hybrids and battery electrics because there is no single technology that holds the key to the world's energy future," said Robert Bienenfeld, senior manager of environment and energy strategy for American Honda.

Other automakers are pursuing a range of fuel-efficient technologies, too. A number of major automakers offer CNG-capable vehicles internationally, but none seems in a rush to enter the U.S. CNG passenger car market.

Ford, for instance, has offered at least two CNG cars in Germany, the Ford C-MAX CNG and Ford Focus CNG, and the Ford Ikon Flair CNG in India. The company does offer light-duty CNG vehicles in the United States for fleet use, but hasn't announced any plans to offer dedicated CNG passenger cars to the public.

Similarly, Volkswagen AG offers CNG vehicles in Europe but doesn't offer them in the United States and hasn't made plans to because the infrastructure is lacking and consumer demand is very low.

Fiat, a world leader in producing CNG vehicles, offers all types of them, including small passenger cars, buses and large trucks. The company commands more than 80 percent of the European market for CNG vehicles and could be a major player in the U.S. natural gas car market down the line.

Chrysler Group LLC, Fiat's global business partner, is "excited about the potential for natural gas powered vehicles becoming successful in the marketplace," Reg Modlin, director of regulatory affairs at Chrysler, said in his testimony to the Senate Energy and Natural Resources Committee in July. But for now, the company is focusing on the heavy-duty sector, because trucks and vans can more easily accept a large fuel tank.

Natural-gas-powered cars play catch-up
Though it's home to a wealth of natural gas, the United States is well behind other countries in adopting natural gas vehicles. There are 15 million natural gas vehicles worldwide and only 120,000 to 130,000 in the United States, where they represent less than 1 percent of new vehicle sales.

The lag "has more to do with the fact that the energy landscape has changed so substantially and that the market is working to catch up," said Kathryn Clay, executive director of the Drive Natural Gas Alliance, a group representing the natural gas industry that lobbied hard for credits under the new fuel economy rule. "But it is catching up."

Some projections have sales levels jumping to 10 percent in the next two decades.

But it's a gamble at best to think natural gas vehicles will roll out quickly enough to spread fueling stations across the country so that FCEVs can have access to hydrogen.

There's also currently no cost-effective way to capture the carbon dioxide produced in making hydrogen from natural gas on site at a fueling station, which would undermine any climate benefits. Carbon capture would be more feasible at a centralized facility.

The real barrier, however, is the logistics of coordinating the expansion of two nascent, expensive and potentially competitive technologies.

"It wouldn't be a great strategy for natural gas people to hope and wait for hydrogen fuel cell vehicles in order to make a mutual strategy," said Nicholas Lutsey, program director at the International Council on Clean Transportation. "And if I really wanted fuel cell vehicles, I don't think it would be a necessary step to go through natural gas vehicles, either."

Reprinted from Climatewire with permission from Environment & Energy Publishing, LLC., 202-628-6500