Air Power

[ffvben]

http://www.earthtoys.com/emagazine.p...rticle=air_car

this is the first time I've seen this air car. It must take a bunch of power to run the air compressors to fill this car up. It looks like a neat idea, powered by compressed air, double mileage compared to electric cars and it has ice cold a/c. just a few mins to fill at a station or plug in at home for 3-4hrs and it goes 10hrs round trip.

[cfg83]

ffvben -

Here's a previous thread on it :

an air car?
http://www.gassavers.org/showthread.php?t=3613

CarloSW2

[rh77]

Back in high school, we built a a variety of different vehicles using pneumatic and hydraulic power.

The pneumatic system worked best -- the "gearset" was an impact wrench hooked to a bicycle d?railleur and gears, with the frame from lightweight tubular bicycle frames. Two small tanks at 60 psi powered the wrench. Pulses of power carried the vehicle around the parking lot until the pressure dimished.

LSS, this proved the limitation of range, and the energy required to pump air or hydraulic fluid to the tanks was considerable.

The best application in use these days is the Eaton Diesel-Hydraulic Hybrid on Medium Duty trucks. Momentum from braking is routed a hydraulic system that assists with standing starts and FE. Otherwise, it remains dormant unless significantly braking, or starting from a stop.

RH77

[GasSavers_Ryland]

a car like that is a good idea if you live some place warm, "The atmospheric temperature is used to re-heat the engine and increase the road coverage." if you don't live some place warm then exspect your 0 negative 15 degree exaust then never gets that warm, and your air engine will turn in to a block of cryogenicly frozen metal, it would be simaler to spending all of your time driving a gas car thru a 200 degree desert.
Of course, simaler to how a hydrogen powered car takes almost as much energy to compress the hydrogen as it does to electrolize it, these vehicles are going to take alot of compressed air, and I know that air compressers require alot of electricity and matence, imagine a 220volt air compresser running for 3-4 hours straight like a vehicle like this would have onboard for home refillings.

[DracoFelis]

Originally Posted by Ryland

Of course, simaler to how a hydrogen powered car takes almost as much energy to compress the hydrogen as it does to electrolize it, these vehicles are going to take alot of compressed air, and I know that air compressers require alot of electricity and matence, imagine a 220volt air compresser running for 3-4 hours straight like a vehicle like this would have onboard for home refillings.

Yes, the energy to compress the air has to come from somewhere (grid power, electric cells, mechanical energy from wind, etc). So you shouldn't think of the "air car" as being "free" to run. Rather, I think of this as more of an unusual style electric vehicle (only in this case the storage medium is compressed air, instead of chemical electric batteries).

So I guess the real question is, how efficient are air compressors vs more traditional ways of storing electricity in a car? If the air compressor approach is anywhere near as efficient (in terms of energy out, for electricity put in), than this approach may have some real traction (due to the lower design/build cost, vs more costly electrical batteries to use the electricity directly). OTOH if the compressors are much less efficient (than the batteries we can unrealistically use to store electricity "directly"), than the "air car" is really just another example of a cute hack that doesn't make sense in the larger picture.

So does anyone know what the relative efficiencies of compressed air vs using batteries and electric motors are? As said above, I really think of the "air car" as really just a unique type of EV. So, compared to a more traditional EV, which approach will require more input of electricity to go a given distance?

[GasSavers_Ryland]

the advantages of it tho, would be that the energy storage could in theory be light weight, and cheap to build, altho most of them are using something that resembles a set of carbon fiber scuba tanks, and those are not cheap, but they are light, and weigh less then lead acid batteries.
To make an air car work in cold weather it would defently need a heater, both for passengers and for keeping the engine from becoming a block of ice, and amaricans aren't going to like having to fill more then one tank, a 3rd tank of water making it basicly a steam powered car would be even more ideal in my mind, but then you have to keep the water toped off as well.