
In Nice, France, and Melbourne, Australia, people are developing engines that run on compressed air.
Moteur Developpement International, in Nice, is perfecting a compressed-air car for public distribution. Someday their cars will be able to travel 4500 kilometres on one tank of air! The engine works the same as a combustion engine, except that the pistons are powered by air instead of tiny explosions of fuel. Because there is no combustion, the engine temperature is much lower, and thus most of the components can be made of lightweight aluminum instead of heat-resistant steel. The air tanks, kept at about 300 bar pressure, are made of carbon fibre, which is not only lighter but will also be safer should the car be involved in an accident—instead of metal exploding and sending shards of shrapnel flying, the carbon fibre will simply crack. All of the components are kept lightweight, which improves the efficiency and the mileage of the vehicle. The air car can get about 200 kilometres of driving per tank, and top speed is about 110 km/h. At a service station, it can be refuelled in about 3 minutes, or you can refill the tanks at home using the onboard compressor, which will fill up in about 4 hours.
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