Fork lifts, buses, tarmac tugs and automatic warehouse vehicles have been running on hydrogen for years. Indeed, industrial gas giant Air Products and Chemicals started refueling buses with hydrogen in 1993 and has long served customers with scooters to submarines.
Now hydrogen cars are getting all the attention. The gloomy outlook for cheap energy has put intense pressure on automakers to come up with vehicles running on clean, abundant and convenient fuels. Hydrogen is a strong contender. While energy companies do not see a viable market for them until at least 2015, automakers want to sell hydrogen vehicles as soon as seemingly surmountable technical and economic obstacles are removed. After all, Henry Ford began selling automobiles several years before the first gas station was built in St. Louis in 1905.
“People will get excited about the car and that will drive fueling availability. It's difficult to make a business case for selling the hydrogen car when there is no demand. It's all a matter of volume,” says Catherine Dunwoody, executive director of the California Fuel Cell Partnership (CFCP) (http://rbi.ims.ca/5719-556), an advocacy group. “It's very important customers have an excellent experience and get convenient fueling.” As such, carmakers are building small fleets to loan or lease to pioneering consumers, media types and celebrities.
FCVs like the Chevy Equinox, Honda Clarity, Hyundai Tuscon and BMW's Hydrogen 7 are among the 45 or so built so far. Even with consumers clamoring for cheaper and cleaner alternatives to gasoline, moving to an entirely new technology will take years if not decades to clear the formidable technical and economic hurdles.
“Automotive companies are investing significant sums of money, but they still have not made that full commitment nor do I think they should,” says David Greene, lead author of a comprehensive study entitled “Transition to Hydrogen FCVs & the Potential Hydrogen Energy Infrastructure” (http://rbi.ims.ca/5719-557) released in March. The report produced three market scenarios (see chart, below left) covering the years 2012-25 and assumes all the cost and technical goals outlined by the Dept. of Energy are met on time which is not yet the case.
For its part, the DOE conducts technical research, but refrains from making sweeping pronouncements about hydrogen. “We see pathways to overcome the remaining challenges, but our view there is no silver bullet. There is no one answer,” says JoAnn Milliken, Ph.D. and DOE hydrogen program manager.
Each scenario in the Oak Ridge report also makes assumptions about subsidies, tax credits and incentives on FCVs, hydrogen itself and the refueling infrastructure. Another catalyst could be a commitment to mandatory greenhouse gas limits. Congress and both 2008 presidential candidates support them while President Bush has called only for voluntary limits.
“It looks like we'll commit to a 70 percent reduction by 2050 and that will require either hydrogen or electricity as the primary energy source for light duty vehicles. Who wins the race — the fuel cell or the battery? They both have a ways to go before they're competitive with the hybrid internal combustion engine. If we have a break-through in batteries, we'll see plug-in vehicles. That's the contest,” says Greene. Either scenario — batteries or hydrogen — makes another big and risky presumption: electricity for them will come from renewable and non-polluting sources.
Challenges outside the technical arena also confront automakers. For example, a completely new and capable supply chain will have to be created. “Costs will come down an order of magnitude with mass production, but there are supply issues. The whole supply base has to be built,” says Dunwoody. Today many of the key component suppliers are small and could not ramp into the millions of parts without big investments and huge expansion.
She also points out that first responders have to be trained in the dynamics of hydrogen. The CFCP, she says, has “educated” 1,700 first responders in California about hydrogen and the DOE has established a program to train them. Despite the obstacles, automakers soldier on with hydrogen vehicles. Here's a sampling of three different FCVs (the Chevy Equinox is covered in depth in a related story on page 50).
The Honda Clarity
Honda built the Clarity from the ground up and introduced it at the Detroit Auto Show in January. The company plans to lease 200 of them in southern California for $600 a month so the Clarity could be considered a limited commercial introduction. The electric motor generates 134 hp and is powered by Honda's 100 kW V-Flow fuel cell stack (http://rbi.ims.ca/5719-558). The car produces some of the more impressive numbers such as a 280-mile range and claims to be twice as efficient as a hybrid and thrice that of a gasoline engine.
“Hybrids today are great, but you can't hybrid-ize your way into energy security. You have to move to alternatives to oil,” says Clarity Program Manager Steve Ellis. “A key point is that even with hydrogen from natural gas, we get a 60 percent reduction in CO2 from well to wheel.”
Like GM, Honda must get FCV production costs down and make it more durable. Honda CEO Takeo Fukui said recently in the Wall Street Journal the car costs tens of million of yen to build now and must fall below 10 million yen or $92,000.
“It's too high in cost and a Honda customer would be disappointed if it only lasted for 100,000 miles. It has to be at least as good as traditional automobiles and have a stunning design,” says Ellis.
A complete refueling only takes a few minutes, whereas the Chevy Equinox FCV took about 7 min from half full. The time it takes to refuel a vehicle could test a consumer's patience at the pump. Asked when a mass market will develop, Ellis expresses the same caution as other stakeholders.
“That's the 48 billion dollar question. Moving to a whole new technology is a scary business,” Ellis says. “The industrial revolution started 150 years ago and we're just getting out of it. Any new technology takes time. It just takes time. Hydrogen is further ahead than anyone dreamed it would be 10 years ago.”
BMW Hydrogen 7
BMW has taken a different path on two fronts with its 7 Series. BMW engineers opted for an internal combustion engine and liquid hydrogen fuel while most automakers use fuel cells and hydrogen gas. The car also runs on gasoline and could start coming off the assembly line quickly if the market was ready.
“We believe that it is necessary to operate with existing fuels in combination with hydrogen. The second reason is because internal combustion engines are so well developed. Production, repair, maintenance and efficiency are well known in the industry,” says Tom Baloga, vice president of engineering for BMW North America. “The hydrogen engine can be developed to the point where it is incredibly efficient.”
The other critical design issue for BMW is hydrogen storage. The Hydrogen 7 tank presently holds 10 kg, giving the 260 hp engine a range of a mere 125 miles versus 250, the goal set by the DOE for next year. The car also has a 74-l tank for gasoline and an 8 kg or 17.6 lb tank for liquid hydrogen.
“The most significant thing in terms of cost is the super-insulated (hydrogen) tank. If you put a cup of hot coffee in the tank, it would still be warm after three months. The super insulation is necessary to keep the liquid hydrogen from warming up. It is stored at -450F,” he says.
The tank has a stainless-steel shell with a 1-inch gap containing stainless-steel foil in a vacuum that Baloga says is equivalent to 50 ft of Styrofoam insulation. The hydrogen is pulled from the top of the tank where it has already started to turn into gas and then is warmed through a series of tubes as it travels to the engine.
“Sealing is important because hydrogen is extremely evasive, but (hydrogen) storage is no more dangerous than gasoline,” says Baloga.
BMW is working with fuel cells, but in auxiliary power units to, for example, provide electricity when an engine is not running. Baloga is reluctant to say which technology will win out, the engine as we know it or fuel cells as primary power. “We should not pick winners and losers because we do not want to exclude other technologies.
There are Macs and PCs, cable and the dish and iPods and MP3 players. But hydrogen looks like the most promising (energy) carrier for the future.”
The hydrogen infrastructure for FCVs is often characterized as a chicken or egg problem in terms of which will come first. Baloga puts it a bit differently. “It's really about the chicken and the food.”
Like BMW, Mazda is unsure about FCVs and instead has opted to use hydrogen in internal combustion engines. The rotary engine in its RX-8 sports car can run on hydrogen or gasoline.
Hyundai Tuscon & i-Blue
Last September, Hyundai introduced its i-Blue FCV which was built from scratch and resembles the Honda Clarity. One of the car's most distinguishing features is its whopping 370-mile range, double most other FCVs. It promises to go up to 100 mph.
“Designing a vehicle from the ground up gives you a lot of design flexibility. You can pretty much gut the front end of the car,” says Todd Suckow, a senior engineer with Hyundai America Technical Center.
Hyundai's also retrofitted a small fleet of Tuscon SUVs to operate in small areas around California for its second generation FCV. Hyundai has partnered with both UTC Fuel Cells which built its fuel cell stack, Chevron as a hydrogen provider and Dynetek Industries, which built its 40 gal hydrogen storage tank. The vehicle boasts a range of 186 miles and a top speed of 93 mph.
“The big design challenge is we built it from the ground up but used the existing platform,” says Suckow. Fitting in three hydrogen tanks where there is room for one gasoline tank is a challenge as is the cooling for the fuel stack which requires a larger radiator.