From Air-Car Ready for Mass Production:

The world’s first commercial compressed air-powered vehicle is rolling towards the production line. The Air Car, developed by ex-Formula One engineer Guy Nègre, will be built by India’s largest automaker, Tata Motors.

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The CityCat model will clock out at 68 mph with a driving range of 125 miles.

Refueling is simple and will only take a few minutes. That is, if you live nearby a gas station with custom air compressor units. The cost of a fill up is approximately $2.00. If a driver doesn’t have access to a compressor station, they will be able to plug into the electrical grid and use the car’s built-in compressor to refill the tank in about 4 hours.

The compressed air technology is basically just a way of storing electrical energy without the need for costly, heavy, and occasionally toxic batteries. So, in a sense, this is an electric car. It just doesn’t have an electric motor.

There’s a constant buzz about air cars, and I’m not sure what to make of them. The article above mentions that the company making this model has plans to expand into 12 countries beyond India, including Germany, Israel, and South Africa, plus a hybrid version with a very small on-board gasoline engine to refill the air tank, ala a series hybrid that recharges its battery pack via its own engine.

Looking at the numbers above, you can drive one of these micro cars for about 1.6 cents/mile, which is insanely low. A Civic-sized EV recharged at 10 cents/kWh gets about 5 miles/kWh, which is 2 cents/mile, and the air car would be vastly cheaper since it replaces the high tech battery with a low tech air tank. Even if you assume that a larger air car would have the same cost/mile as an EV, the lower initial cost would still make it a much more attractive alternative, if all other things are equal.

And that’s the rub–are all the other relevant factors equal? I honestly don’t know. How do you run your electrical goodies in the car–is that done with a generator driven off the engine? What is the reliability of the air tank, lines, and engine, especially under wildly varying weather conditions? Does it make a really embarrassing farting noise when you drive down the street? (Think I’m kidding? Try selling a car that did do that to the US public, and see how far you get, beyond, you know, the Weird Al Yankovic fans.)

And if this is such a good idea, why don’t we see them being built and sold in the US by GM or Honda? It could be as simple as those companies not wanting to start a trend of drivers here buying much cheaper cars, which not coincidentally, tend to have a much lower profit margin?

It’s entirely possible that air cars could have a huge future. Imagine the following scenario: Peak oil starts to bite deeply into modern economies, even our best efforts to reduce the price of batteries for plug-in hybrids and EV’s fail, and hydrogen remains a pipe dream. We could then see a tremendous demand for air cars (both pure and hybrid) as an indirect way of electrifying a large portion of personal transportation.

I think it’s far too early to reach any conclusions about air cars, other than to say that they belong in the “really interesting concept that bears watching” category.