General Motors Corp, Japan's Honda Motor and Germany's BMW are pursuing competing technologies to introduce new "zero emission" cars that run on fuel cells and do not pollute, said engineering and marketing managers for the three automakers.

BMW, however, may have a leg up to market a new car in California and Europe powered by a gasoline engine and a hydrogen fuel cell system. The German automaker plans to offer a limited number of the new model in its 7 Series in 2010, Wilhelm Hall, general manager of environmental engineering at BMW North America.

He spoke at a briefing for reporters on California's efforts to persuade automakers to manufacture more environmentally friendly cars for California's "hydrogen highway."

BMW plans a production run of the new car "in the hundreds" in five years with sales aimed at fleet operators and individuals in Europe and the U.S., Hall told Reuters.

California drivers, battered by soaring prices at the gas pump, are snapping up new cars like Toyota's gasoline-electric Prius hybrid combining smart looks and high miles-per-gallon.

PRIUS VS HUMMER

Hollywood celebrities have adopted the quiet Prius as a kind of environmental badge of honor, while plenty of gas-guzzling Hummers continue to roar over the state's freeways where they are the object of envy and scorn.

California, which has paced the U.S. in implementing regulations to reduce greenhouse gas emissions linked to global warming, aims to promote the use of hydrogen fuel to reduce its dependence on oil while improving the environment.

The state's "hydrogen blueprint," one of Schwarzenegger's favorite programs, calls for up to 2,000 hydrogen vehicles and 100 refueling stations by 2010 at an estimated cost of $54 million.

The fuel outlets would be concentrated in San Diego, Los Angeles, the San Francisco Bay area and Sacramento.

Depending on the results of the first phase, California would aim for 20,000 hydrogen vehicles and 250 fuel stations.

GM is developing a demonstration car called the Sequel powered by a compressed hydrogen engine, said Al Weverstad, executive director of GM's Public Policy Center.

Weverstad said GM will complete its engineering analysis on hydrogen vehicles by 2010, but no timetable has been set for production and marketing programs. GM is concerned about development costs, he said, but added: "We are confident we will get there."

Honda has developed a hydrogen fuel cell demonstration car and also a car running on compressed natural gas that can be refueled at home.