But U.S. automakers are now zeroing in on half hybrids, which would use small motors to electrically assist gasoline engines. They would improve mileage by 10 to 20 percent but cost less to build. Ford and GM plan to offer half-hybrid SUVs by 2004. They will utilize hydrogen, one of Earth's most abundant resources. In a fuel cell, hydrogen and oxygen merge, forming water and releasing electricity.
Fuel cells are two to three times as efficient as combustion engines.
With abundant hydropower, Iceland hopes to generate hydrogen for a fleet of cars, trucks, buses, even fishing trawlers. They are so clean that one model, the Honda Civic GX, tied for first place in a list of the most environmentally friendly vehicles in the U.S. this year. And the old gray mare ain't dead yet. Gasoline engines power 10 of the 13 greenest cars and trucks evaluated for 2001 by the American Council for an Energy-Efficient Economy. Electric and alternate-fuel vehicles have dominated past winners lists.