Hydrogen cars to hit the road by 2015?

Kevin Eslinger, a graduate student at the UC Davis Institute of Transportation Studies, points to one of the projects the university is studying: a Toyota SUV that runs on a hybrid electric/hydrogen engine (see video). "We drove this past 100 miles per hour," Eslinger said. And it accelerates as well as a standard gas car, he added.

The car, along with an electric/hydrogen Ford Focus, is on display at Semicon West, a chip equipment technology conference taking place here this week.

Hydrogen fuel cells and other energy technologies are making their mark at Semicon, as the semiconductor and chip equipment industries try to more aggressively expand into solar panels and transportation. These companies specialize in laying down intricate chemical patterns onto films and surfaces, which is also a principal task in making solar panels and alternative energy engines.

Hydrogen, once the darling of the alternative energy world, has been on the skids lately, with critics complaining that difficulties with storage, production and transport of the gas make it impractical and uneconomical as a fuel source. In addition, petroleum conglomerates are devising cleaner car fuels.

Nonetheless, some believe the concept has promise, and hydrogen research continues to be funded. In 2004, the Department of Energy said it would spend $350 million over four years on hydrogen research.

Hydrogen will also cut down on greenhouses gases, its advocates say, because only water comes out of the tailpipe. However, manufacturing hydrogen, which involves combining methane with water and heating up the mix to 815 degrees Celsius, produces 9.3 kilograms of carbon dioxide for every kilogram of hydrogen. Some companies are tinkering with ways of sequestering manufactured carbon dioxide in underground caves and other storage facilities to keep it from getting into the atmosphere.

Car manufacturers acknowledge that the concept won't take off unless such problems can be conquered. Filling stations will also have to be built. But they believe that cars fueled by hydrogen could hit the road sometime between 2015 and 2020.

Hydrogen fuel cell cars actually run on electric engines, but the electricity comes mostly from a chemical reaction. Hydrogen and water pass through membranes in the fuel cell. The membranes extract electrons, which then charge a battery that powers the motor.

Battery charging, meanwhile, is supplemented by regenerative braking, a technology used with conventional gas/electric hybrid cars. In regenerative braking, the work involved in slowing the car generates electricity. (In a normal car, energy consumed to slow the car gets lost as heat.)

Video: Ford fills up with hydrogen
Check out a Ford Focus that runs on a hybrid electric/hydrogen engine.

Video: Toyota's hydrogen SUV
Get the lowdown on the Highlander with a hybrid electric/hydrogen engine.

Toyota's fuel cell car, which is based on the Highlander SUV, contains four torpedo-shaped tanks that in total contain 3.5 kilograms of compressed hydrogen. The hydrogen comes out of the pump at about 500 pounds per square inch. The car gets about 60 miles per kilogram, giving the car a range of about 200 miles.

The Ford Focus, meanwhile, has a similar range but has been cranked up to reach speeds of just 80 miles per hour, a Ford representative said. The hydrogen tanks consume most of the trunk space.

Volkswagen has demonstrated a similar hydrogen fuel cell car, but like the Ford Focus it tops out at around 80 miles per hour.

BMW is also interested in hydrogen. The carmaker is experimenting with an engine that burns hydrogen directly in the combustion process. Ideally, this would lead to greater horsepower. BMW said its car will run on liquid, rather than compressed hydrogen.