"Lots and lots of things are happening that indicate a worldwide interest, and most of the knowledgeable people are convinced that the next-generation replacement for the internal combustion engine is going to be a fuel cell, " Roan said.

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When the battery is depleted (or when driven at very high speeds), the premium-gas internal combustion engine powers the car, but its fuel mileage suffers from having to shove around 400lbs of batteries.

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The technology isn't new-a patent for a hydrogen internal combustion engine was issued in 1928, and a 20hp fuel-cell tractor was demonstrated in the late 1950s.

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It can be used to run an internal combustion engine in a car or power one using a fuel cell, with heat and water as the only emissions.

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Burns says a fuel-cell vehicle has one-tenth the number of parts of a traditional internal combustion engine.

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