Tata Motors, once derided as the company with a name that sounds like it ought to be spread on a Fillet-o-Fish, has been making some serious forward movement in the past year or two.
Now, hot on the heels of its recent acquisition of Land Rover and Jaguar, and news of the impending assault on the European market with the Tata Nano, the Indian company is set to release a car powered entirely by air. But is it all hot air? (You see what I did there.)
Turns out it's very much a legitimate prospect. Sure, it looks bloody ordinary, but let's look beyond the styling for the moment. The MiniCAT (Compressed Air Technology), invented by French madman and ex-F1 engineer Guy Negre and his company Motor Development International (MDI), is a lightweight fibreglass urban car built around a tubular chassis which is glued together rather than welded. More importantly than that, and as you've no doubt gathered, it's powered entirely by compressed air.
Around 6000 of these zero-emissions Air Cars are planned to blow onto Indian streets by 2010.
Tata's Air Car, which MDI calls a MiniCAT, is expected to cost the equivalent of $8177 in India, and would have a range of about 300km between refuels—an event which, due to the fact you're only paying for the power needed to work the compressor, would cost around $2. Until the market for this car is properly developed though, owners will find included a small compressor which can be connected to any regular power supply, and will refill the tank within 3-4 hours.
If all that weren't enough, the Air Car's lack of a combustion engine means that the need for regular oil changes is a thing of the past, as new oil is only needed every 50,000km. That's one very welcome extra zero on the end.
Here's some nifty bullet points for you.
• The Air Car runs a specially developed piston engine that uses a new thermo dynamic cycle offering exceptional energy efficiency.
• Compressed air is stored in carbon fibre tanks, at 300 bar (4,351 psi).
• The CAT engine operates on four cycles: intake and compression, combustion, expansion, and exhaust.
• Outside air is drawn into the compression chamber and compressed to 20 bar (290 psi). At the highest point of pressure (at ‘top dead centre’), this air reaches 400°C (centigrade), and, at that point, air from the storage tank is injected into the combustion chamber.
• Since the injected air is much colder than the compressed air in the chamber, the injected air is heated instantaneously, causing a sudden expansion, which pushes the piston down (in an expansion stroke) • The air tanks fitted to the underside of the vehicle can hold 300 litres of compressed air, capable of driving the MiniCAT for up to 200km.
• Using a household electrical source, it takes about 4 hours for the vehicle to refill its own compressed air tanks (a rapid three minute recharge is possible using an external high-pressure air pump.
• The MiniCAT runs an electronically controlled continuously variable transmission (CVT)
Hmmm - this is lifted 'in toto' from a two year old report
ReplyDeleteeg
http://www.themotorreport.com.au/5732/tata-air-car-powered-entirely-by-compressed-air-blow-me-down
Attractive as the comments inferring conspiracies by oil cartels might be, I have done some calculations on the potential energy inherent in a 300l tank of air compressed to 300 bar.
The shortfall in comparison with the claimed range is so stark that I personally consider this to be scam engineering, a repackaging of the central precepts of perpetual motion, and that to me is sufficient explanation for why this idea (which has been around about a whole decade) keeps going nowhere.
The explanations hint at some novel way of unlocking the heat energy inherent in the compressed air. This would either require a massive temperature difference between the tank (hot) and ambient, or the extraction of massive amounts of heat from ambient air, which could not possibly happen in the time available (and if it could, the vehicle would act like a mobile blast freezer.)
In 2002 the taxis in Mexico city were all going to be swapped over to CAT technology; nothing happened.
In 2008 a vehicle was to be entered in an international contest against other alternative fuel vehicles. Again, nothing seems to have happened.
Compressed air at 300 bar realised through a half inch hole to atmosphere will cool to -3 deg centigrade there in lies the trick so no need for a (and if it could, the vehicle would act like a mobile blast freezer.) as you so eloquently said Anonymous
ReplyDeleteRead this
http://auto.howstuffworks.com/fuel-efficiency/vehicles/air-car.htm
In December 2009 Tata's vice president of engineering systems confirmed that the limited range and low engine temperatures were causing problems
ReplyDeleteWhich seems to support what the first poster said about the unrealistic claims and the thermodynamic improbabilities.
Howstuffworks link reads like it was written by a journalist. I've yet to see anything that doesn't read like that, unless it was written by a publicist.
I haven't talked to an engineer or a scientist who thought this was not a scam.
Nothing Tata has said suggests they've got any further in the last four years than they said they'd gotten in 2008. The song remains the same. I think they must be hoping if they postpone it for long enough they can retire, be bought out, or the stockholders will forget or die, so they are spared having to admit they've been taken in.