French motor manufacturer Peugeot Citroën hopes to launch a range of small cars by 2016 which will be part-powered by compressed air.
The vehicles will have conventional petrol-fuelled engines to enable driving on out-of-town roads and motorways.
However a compressed air system would be available for urban motoring. The system could see the cars running at more than 140 miles a gallon.
The cars would not require batteries made of expensive materials, such as lithium.
Heat released when braking would help fill a tank of compressed air that sat along the middle of the vehicle and which powered its wheels.
Drivers would be able to solely use the car’s petrol engine, its compressed air power source, or a hybrid of the two, according to Peugeot Citroën.
According to sources the cars would feature 82bhp and 110bhp engines, which would be used in conjunction with the compressed air system.