Tata OneCAT

An engineer has promised that within a year he will start selling a car that runs on compressed air, producing no emissions at all in town.

The OneCAT will be a five-seater with a fibre-glass body, weighing just 350kg and could cost just over £2,500.

It will be driven by compressed air stored in carbon-fibre tanks built into the chassis.

The tanks 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.

"The first buyers will be people who care about the environment," says French inventor Guy Negre.

"It also has to be economical."

Major savings

Mr Negre has been promising for more than a decade to be on the verge of a breakthrough. Independent observers are more convinced this time because he recently secured backing from the giant Indian conglomerate Tata to put the finishing touches to the engine.

The compressed air is stored in carbon-fibre tanks

Tata is the only big firm he'll license to sell the car - and they are limited to India. For the rest of the world he hopes to persuade hundreds of investors to set up their own factories, making the car from 80% locally-sourced materials.

"This will be a major saving in total emissions," he says.

"Imagine we will be able to save all those components travelling the world and all those transporters."

He wants each local factory to sell its own cars to cut out the middle man and he aims for 1% of global sales - about 680,000 per year.

Terry Spall from the Institution of Mechanical Engineers says: "I really hope he succeeds. It is a really brave experiment in producing a sustainable car."

But he said he was interested to see how the car would fare with safety tests and how much it would appeal to a public conditioned to expect luxury fittings adding to the weight of the vehicle.

Mr Negre says there's no issue with safety - if the air-car crashes the air tanks won't shatter - they will split with a very loud bang. "The biggest risk is to the ears."

videos ( on this technology can be found on YouTube

MDI's AIRpod Is a Minute Air-Powered Car

Europe-based company MDI Corporation already promised a six-seater compressed air-powered car for the US come 2010. Here's another vehicle from the brand, although it's far from the family-sized vehicle the US will get. The AIRpod is a minute car by MDI powered by compressed air that's slated for a Europe release on 2009. The vehicle can seat three (non-claustrophobic) people, with one forced to sit facing backwards (that someone would probably have to be immune to motion sickness).

The AIRpod has a maximum range of 130 miles (220 kilometers) and a top speed of 40 miles per hour (70 kph), making it suitable for city driving which is probably the company's aim in the first place. Using compressed air as a power source means huge amounts of air are compressed into a small tank that would have to be released slowly to move the car's pistons. As curious as it might look like, the AIRpod is expected to be really efficient and of course, since it runs on air instead of fossil fuels, it's also environmentally-friendly.