CNET también está disponible en español.

Ir a español

Don't show this again


California to experiment with hydrogen buses

If you live in California, you might get to drive in one of these hydrogen buses, to be tested soon through a $24 million project partly underwritten by federal grants.

When you think of the words "hydrogen highway," your mind tends to conjure up images of silent cars whizzing down the road in an environmentally friendly manner.

You don't think about trying to squeeze into a seat between a 300-pound man and a woman with 18 grocery bags. But this scenario might be more realistic.

A GM hydrogen car. Good luck filling up. Mike Kanellos

CalStart, an alternative-transportation advocacy group, has signed five contracts with bus companies to develop and study fuel cells, as well as other components for making hydrogen buses. The $24 million project is partly underwritten by federal grants.

The SunLine Transit Agency in Coachella, Calif., for instance, plans to street-test a hydrogen bus being built by American Fuel Cell. The fuel cell in the car comes from UTC Power and lithium ion batteries. AC Transit in the Bay Area, meanwhile, will stress-test hydrogen buses with UTC to identify the weakest points in hydrogen drive trains. BAE Systems will develop a hydrogen-diesel hybrid.

Car manufacturers such as Toyota Motor, General Motors, and BMW have proven that hydrogen cars work. (Toyota and GM have fuel cell hydrogen cars. The fuel cells strip electrons from hydrogen molecules to power batteries. BMW, meanwhile, has a hydrogen combustion engine in which hydrogen is ignited in cylinders sort of like how gas is ignited today.) Check out our test drive of a hydrogen Mercedes here.

The tough part is the infrastructure. Hydrogen is expensive to make and difficult to transport, and few hydrogen stations exist. Some processes for producing hydrogen can also emit large amounts of greenhouse gases.

Buses can get around some of these problems. City buses drive a limited number of miles a day, and they typically don't drive very far from a maintenance station. Put a hydrogen-manufacturing station and pumps in a central location, and you could serve a city. Las Vegas is already trying this. (The University of California at Berkeley has a hydrogen station too.)