What with rising fuel prices and the need to reduce carbon emissions, the development of a car run by compressed air seems like a very good idea. India’s Tata Motors thinks so too and is backing the project. It seems there is also interest in Australia , supported by the Victorian and Federal governments. Some of you may have already read about this car, developed by a former FI racing engineer, Guy Negre, of Moteur Development International.

The car will be driven by compressed air stored in carbon-fibre tanks- the type used by deep-sea divers. The tanks, built into the chassis, can be filled with air from a compressor in just three minutes at an air-station equipped servo. This is 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 can use all kinds of liquid fuel and can get the equivalent of 120 miles per gallon when fuel is needed.

There are skeptics as to the vehicles’ chances of success in countries such as the US but it will be interesting to see how this car compares with Tata’s own NANO Car. But in a country like India where the car market is growing rapidly and there is considerable city traffic congestion, its encouraging to see initiatives being taken to use renewable energy in low cost cars.

I’m very excited about the MiniCat, and its relatives, the new, air-powered vehicles that we will hopefully see on our roads very soon. Brainchild of former Formula One engineer, Guy Negre, and his son Cyril, the car has been over a decade in development and uses revolutionary engine technology. Of course, anyone who has worked in a commercial garage knows that compressed air powered tools have been around for a long time, and work analogously to the electrical counterparts that domestic users will be familiar with. In principal, to run a car engine only requires something that can push the pistons, and compressed air should work. The problems are similar to those for hydrogen powered cars – how to carry enough of the stuff.

The engine technology has been developed by the family run company, Moteur Development International (MDI), and features an articulated con-rod which allows expansion at constant volume, effectively allowing the same engine efficiency to be achieved with a lower compression ratio. There is also a moto-alternator, which both starts up the compressed air engine, and refills the air storage tanks. These two innovations are not only applicable to compressed air engines, but could also be applied to conventional internal combustion engines to enhance performance.

A major difficulty over the years has been in finding an automotive manufacturer willing to develop the technology, but that is what has recently changed. The Indian car company, Tata has agreed to take the development forward, and we may be able to see these cars in India and the USA by the end of 2008.

If this is successful, we could see a genuine revolution in car technology. With the cheapest model expected to sell at about 3,500 Euros, the MiniCat should be able to refill from a high pressure air line (as exist in garage forecourts already) in around 2 minutes. The top speed is expected to be about 110 kilometers per hour, and with a refill costing only around 1.5 Euros, and lasting for 200 kilometers, this cheap and completely non-polluting little car will appeal to the vast majority of city motorists.

MiniCat also has an appealing, fresh design, with the driver positioned centrally, and passenger seats either side. Future plans have been made for other models, specifically for use as taxis, people carriers and even a flatbed truck model. Since the vast majority of car trips are short distance and urban, this is a car that is affordable, green and economical. I can’t wait to see it.

Amanda