[Slim1950]

Has anyone investigated (compressed) air powered cars? Seems to be an up and coming technology. Are they going to be a viable alternative? So far I cannot find any DIY-ers in this field. Or I don't know where to look.

[Mastiff]

Compressed air powered cars are very interesting.

They're basically the exact same design as a Steam Engine, minus the water boiler.

You could possibly actually use a large steam engine and run it right off the compressed air.


The most difficult part of building a compressed air vehicle is getting the very light weight composite air tanks.

A standard steel compressed air tank from your local Airgas is seriously heavy and won't work well.

[JRP3]

The air car looks like crap to me. A really inefficient way to store electrical energy.

[ga2500ev]

Originally Posted by JRP3

The air car looks like crap to me. A really inefficient way to store electrical energy.

There are several advantages I see in a compressed air system (CAS) that makes it worth taking a look:

1) Weight Reduction: With the use of carbon fiber tanks the weight of the system is essentially the weight of the tanks.

2) Cost: not the electric cost, which of course is higher due to inefficiency, but that the costs of the tanks will be significantly less than the costs of batteries. In addition, tanks don't wear, so you won't have to replace them.

3) Fast refillability: Air tanks can be quickly filled from tanks of precompressed air, which can then be later refilled. So at least in theory filling a CAS vehicle would be more like filling a gas tank, as opposed to having to plug in for an extended period of time.

4) Free AC: decompressing air cools it, by capturing that coolness and transferring it to the cabin, AC can be achieved as a byproduct of running a CAS engine.

5) Improved efficiency using waste heat. Heated air expands more. So more power can be obtained by heating the air as it is used. Any heat source is usable for this process. A lot of the wasted electricity in compressing air is generated as heat. By capturing this heat in the vechicle in an insulated system and reusing that heat (or the heat of braking)
to heat the gas, the efficiency of that CAS system will improve the range of the vehicle.

6) Regenerative Braking. A CAS system facilitates recapturing the energy of braking by compressing air back into the tanks.

Using a electric traction motor and battery system coupled with a CAS system that drives a generator can facilitate a fast fillable, regen, lightweight plugin hybrid with extended range. And it's still an all electric hybrid instead of a gas electric hybrid.

Finally if we start using renewable energy such as solar, then the fact that air compression is inefficient isn't as critical.

I have another post on this subject on the forum. I'd love to discuss the idea some more.

ga2500ev

[JRP3]

Carbon fiber tanks that can handle high pressures would be very expensive.
On board tanks just can't hold that much energy and range is limited.
The distances claimed for the air car have not been shown at all in the real world.
Both the compressor and decompresser, (engine), suffer from similar inefficiencies and wear and tear as an ICE. An ICE is essentially an air compressor after all. So now you would have oil changes on the compressor and air engine as well.

[Coley]

It would take a lot more energy to pump up the air tanks, than it would to charge a lith-ion battery pack.
Not worth the effort to me either.....

[KiwiEV]

My main problems with the air car are:
1: Noise & Vibration
2: Cost of home-refilling
3: Time to home-refill
4: Paper-like vehicle construction

I guess noise & vibration could be reduced to an acceptable level with dampeners, mufflers and noise canceling matting throughout the car. It would weigh the car right down though reducing it's range.
You could always set up a rooftop solar array to generate electricity to power an inverter to power the compressor that refills the car (that ate the dog that ate the cat that lived in the house that Gavin built). LOL
Of course the range isn't toooo bad on those air cars because they weigh less than a toaster. But once you load them up with airbags. noise/vibration canceling equipment and make them solidly built - wham, there goes the range.
I'm still very very interested in the idea of the air car but electric strikes me as much more impressive for now.

[DVR]

Could someone post a link to the Aircar? I havent seen it.
I saw a fella on "The new Inventors" a few years ago that had what looked kind of like a Wankel type air motor that was supposed to be quite efficien.t It impressed the hell out of the judges. Wonder what happened to him?

[Uncle Joseph]

Here's a short video on the MDI Air Car.

MDI Air Car

There company website at www.theaircar.com doesn't have any useful pics or videos that I could find. I think Air Car Factories is a new company formed with MDI as the designer.

[mattW]

I wrote a blog about them in case you missed it... It seems promising but it needs big infrastructure changes to have it work whereas EVs just need powerpoints, but i've collated a bunch of info in the blog post.