An engineer has promised that within a year he will start selling a car in India that runs on compressed air, producing no emissions at all in towns.
The OneCAT will be a five-seater with a glass fibre body, weighing just 350kg and could cost just over £2,500.
The project is being backed by the Indian conglomerate, Tata for an undisclosed sum. It says the technology may also be used for power generation.
The car will be driven by compressed air stored in carbon-fibre tanks.
The tanks, built into the chassis, can be filled with air from a compressor in just three minutes - much quicker than a battery car.
Alternatively, it can be plugged into the mains for four hours and an on-board compressor will do the job.
For long journeys the compressed air driving the pistons can be boosted by a fuel burner which heats the air so it expands and increases the pressure on the pistons. The burner will use all kinds of liquid fuel.
The designers say on long journeys the car will do the equivalent of 120mpg. In town, running on air, it will be cheaper than that.
Analysts say the fact that the project has the backing of an internationally well known company such as Tata makes the idea much more marketable.
The Indian company - which will put the finishing touches to the engine - says it is even considering using the technology for power generation.
Parts of the country are desperately short of electricity supplies. On Tuesday officials announced that Delhi and Moscow had finalised plans for Russia to build four new nuclear power stations in India.
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