According to the trend-spotters PSFK, there's a company named Zero Pollution Motors who will be releasing compressed air powered cars in United States by 2010. Designed by France’s MDI, the vehicle is 100% emmision free when running on air-only mode.
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Allegedly, $2 worth of air is all it takes to fill the tank, and the car gets 106 petrol equivalent mpg. Top speed when running on air is 35mph, but a small fuel boost (gasoline, propane, ethanol or bio fuels) ramps it up to 90mph.
The compact cars can seat 6 people and has room for luggage, and is set to sell for around US$18000.
Via: PSFK