Expanding uses for compressed air

An engineer has promised that within a year he will be selling cars in India that run on compressed air and produce no emissions. French inventor Guy Negre's OneFlowAir car will be a five-seater with a glass fibre body, weighing just 350kg and it could cost little more than £2,500. Then there's the CityFlowAir – still not beyond the pockets of most drivers, with a price tag of around £13,000 D which can hit a very respectable 68mph, with a range of 125 miles. Add to that the MiniFlowAir and MultiFlowAir – a new urban public transport concept in the form of a train on wheels, comprising a driver's car and several wagons – and it isn't hard to see why so many interested parties, from commercial to environmental, see the compressed air car range developed by Negre's Motor Development International (MDI) as one of the best things to have happened to the motor engine in years. Apart from the low cost of the vehicles and environmental appeal, there is the massive savings to be had on fuel. Not only will it take just a few minutes for the CityFlowAir to refuel at gas stations equipped with custom air compressor units, but, says MDI, it should cost only around $2 to fill the car up with 340 litres of air! The car will be driven by compressed air stored in carbon fibre tanks. Built into the chassis, these can be filled with air from a compressor in just three minutes – much quicker than recharging a battery-powered 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 that 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 the car will do the equivalent of 120mpg on long journeys. In town, running on air, it will be cheaper than that. The fact that the project has the backing of internationally recognised company Tata Motors has made 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. "The first buyers [of the compressed air car] will be people who care about the environment," says Negre. "It also has to be economical." Tata is the only big firm that he will license to sell the car – and it is 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 car sales – about 680,000 per year. Meanwhile Zero Pollution Motors (ZPM), the North American representative of MDI, is also gearing up to introduce a six-seat, four-door family-size compressed air vehicle to the US market. The ZPM model is expected to achieve more than 100 MPGe and in excess of 90mph, have zero to low carbon emissions, offer plenty of space for luggage, meet all safety requirements and cost no more than an average economy to mid-size vehicle. ZPM plans to build and operate the first CAV (compressed air vehicle) plant in the US and expects the first cars to roll off the production line in late 2010 or early 2011, according to CEO Shiva Vencat. All of which is good news for MDI – and the emerging CAV industry. It seems the uses for compressed air are now being extended way beyond the boundaries of what was once thought possible – and will continue to do so, as long as there are people around with the drive and imagination of Guy Negre and Seamus Garvey (see panel, right).