Tuesday, January 31, 2012

Compressed Air Car

I don't think I believe this.  Watts Up With That? reports that Tata Motors of India is about to start production of a car that uses compressed air to run the four cylinder engine.
According to the designers, it costs less than 50 rupees per 100 KM, that’s about a tenth the cost of a car running on gas. It’s mileage is about double that of the most advanced electric car, a factor which makes it a perfect choice for city motorists. The car has a top speed of 105 KM per hour or 60 mph and would have a range of around 300 km or 185 miles between refuels. Refilling the car will take place at adapted gas stations with special air compressors. A fill up will only take two to three minutes and costs approximately 100 rupees and the car will be ready to go another 300 kilometers.
Best of all: the "exhaust" is clean, subfreezing air, so that provides your air conditioning system.  (No heater, but I was not aware that an Indian car maker would worry about that.)

Color me skeptical.


  1. Compressed air cars have been tried before, in France.

    So I believe they're doing it, at least as a trial.

    It's also crazy inefficient, which is why it's never caught on.

  2. The fact that this is not already widely used despite the lack of significant barriers should give an idea of how practical it really is.

    Look at forklifts for example.

  3. Amazing claims require amazing proof, or something like that.
    So, is this a "car" because it has four wheels and carries two people? I can't imagine compressed air in any size tank containing enough potential energy to move anything more than the tank, a bicycle or two, and a couple of people who don't weigh much. I'm willing to bet that this "car" is just such a stripped down vehicle, with the compressed air engine, and pedals for those times when the air pressure doesn't get you where you're going.

  4. Here's a pretty good article on air cars: http://auto.howstuffworks.com/fuel-efficiency/vehicles/air-car.htm

    Not very practical with lots of drawbacks. It might be a viable option as a special kind of short traveling distance rental car (assuming one is willing to be in a tiny car (tinier than anything including the typical compact car).

    Doesn't address the problem of where the electricity to run the compressor to fill the tank will come from....are we going to invest billions (trillions?) to upgrade our electric grid and build nuclear reactors to make this or the electric car viable......hint: solar and wind ain't going to cut it anytime soon!

  5. INR 100 = US$2.00.
    $2.00 / $.135/kw*hr = 14.8 kw*hr
    14.8 kw*hr = 19.86 hp*hr

    185 miles / 60 MPH = 3 hrs

    19.86 hp*hr / 3 hrs = 6.62 hp
    average power

    A Prius is said to require 14 hp to sustain 60 MPH.

    The range/speed claims seem inflated by a factor of 2 or so.