Car that runs on air

karrie

OogedyBoogedy
Jan 6, 2007
27,780
285
83
bliss
Where do they get this 'it costs nothing to fill' idea? Compressed air is not energy free. It is also not emission free, as you have to factor in the power plants it takes to run compressors.
 

Dexter Sinister

Unspecified Specialist
Oct 1, 2004
10,168
536
113
Regina, SK
Any time you hear the phrase "perpetual motion" or "free energy" you can assume you're being lied to. The laws of thermodynamics are unavoidable. It takes energy to move the mass of that car, it comes from compressed air, which took energy to compress, and you can't get out of the compressed air the energy it took to compress it, there'll always be some losses which have to be made up some other way. Eventually it's going to go back to the combustion of something, somewhere, even if it's solar-produced electricity. It will never be possible to run the vehicle on compressed air and use its momentum to drive a compressor to keep it refueled, it'll inevitably run down. The energy used to move the vehicle won't be available to recompress the air, it'll always use more compressed air than it can generate.
 

In Between Man

The Biblical Position
Sep 11, 2008
4,597
46
48
44
49° 19' N, 123° 4' W
Any time you hear the phrase "perpetual motion" or "free energy" you can assume you're being lied to. The laws of thermodynamics are unavoidable. It takes energy to move the mass of that car, it comes from compressed air, which took energy to compress, and you can't get out of the compressed air the energy it took to compress it, there'll always be some losses which have to be made up some other way. Eventually it's going to go back to the combustion of something, somewhere, even if it's solar-produced electricity. It will never be possible to run the vehicle on compressed air and use its momentum to drive a compressor to keep it refueled, it'll inevitably run down. The energy used to move the vehicle won't be available to recompress the air, it'll always use more compressed air than it can generate.

Remember back in the day there was a thread where people posted music videos for what songs they thought suited certain posters, and someone posted "She blinded me with science" for you?

That was suiting... and fun! aaaahh good times.... :)
 

Tonington

Hall of Fame Member
Oct 27, 2006
15,441
150
63
Compressed air is better for storing energy than it is for propelling vehicles. With the intermittent generation from renewable energy, it makes sense to store excess generation during off-peak hours for use during high demand hours. Compressed air is one solution that gets mentioned in gap assessments.
 

TenPenny

Hall of Fame Member
Jun 9, 2004
17,466
138
63
Location, Location
The reason that compressed air is used for tools is that the tools can be much lighter. That's why they're used for assembly lines, mechanics, etc. Not because they are efficient.

As a rule of thumb, the compressor needs to be 5 x what the work you need the air to do. In other words, if you're running an impact wrench that is a 1 hp wrench, you need a 5 hp compressor.
 

bill barilko

Senate Member
Mar 4, 2009
5,866
492
83
Vancouver-by-the-Sea
Any time you hear the phrase "perpetual motion" or "free energy" you can assume you're being lied to. The laws of thermodynamics are unavoidable. It takes energy to move the mass of that car, it comes from compressed air, which took energy to compress, and you can't get out of the compressed air the energy it took to compress it, there'll always be some losses which have to be made up some other way. Eventually it's going to go back to the combustion of something, somewhere, even if it's solar-produced electricity. It will never be possible to run the vehicle on compressed air and use its momentum to drive a compressor to keep it refueled, it'll inevitably run down. The energy used to move the vehicle won't be available to recompress the air, it'll always use more compressed air than it can generate.
How about rubber bands? :lol:
 

Dexter Sinister

Unspecified Specialist
Oct 1, 2004
10,168
536
113
Regina, SK
Or hamsters running in wheels... Might get a thousandth of a horsepower out of a hamster, a rubber band maybe a millionth. Unless it was a really BIG one.
 

Angstrom

Hall of Fame Member
May 8, 2011
10,659
0
36
They have Car's that run on Compressed Air in India already.
Its used for city driving and works fine
They only need a tiny bit of gas to compress the air.
Nothing even close to what our car's use up and even better then hybrids.
Its really smart so don't plan on seeing this in NA any time soon.
 

Unforgiven

Force majeure
May 28, 2007
6,770
137
63
Any time you hear the phrase "perpetual motion" or "free energy" you can assume you're being lied to. The laws of thermodynamics are unavoidable. It takes energy to move the mass of that car, it comes from compressed air, which took energy to compress, and you can't get out of the compressed air the energy it took to compress it, there'll always be some losses which have to be made up some other way. Eventually it's going to go back to the combustion of something, somewhere, even if it's solar-produced electricity. It will never be possible to run the vehicle on compressed air and use its momentum to drive a compressor to keep it refueled, it'll inevitably run down. The energy used to move the vehicle won't be available to recompress the air, it'll always use more compressed air than it can generate.

Skepticism is good Cynicism isn't. Prefixing perpetual motion with what if as happens in the video, removes the lie from the claim.

Though from the video most of the details are left out, it does beg the question "is this better than what we currently have?" With gas at $1.29 a liter, probably. Even using a gas engine to compress the air to begin with, the amount of fuel used is far less than the amount of gas it would use to move the car the same amount. If anything, it appears on first blush to be simply a more efficient way to use that fuel. That's the important thing here.
 

cranky

Time Out
Apr 17, 2011
1,312
0
36
200 miles per tank?

I have a 30 gallon tank on an aircompressor, and I can't get 10 minutes of turning a disc grinder without it requiring more air.
 

taxslave

Hall of Fame Member
Nov 25, 2008
36,362
4,337
113
Vancouver Island
200 miles per tank?

I have a 30 gallon tank on an aircompressor, and I can't get 10 minutes of turning a disc grinder without it requiring more air.

Try using a 1 in impact. Takes about 11 cubic feet/min at 120 psi. I don't see a car using much smaller motor so unless they have found a way to make a much more efficient motor. The video doesn't show much of the important parts. More like a dog & pony show.
 

Unforgiven

Force majeure
May 28, 2007
6,770
137
63

Ron in Regina

"Voice of the West" Party
Apr 9, 2008
23,207
8,048
113
Regina, Saskatchewan
I received an Email a while back about something like this:

YouTube - ‪How an Opposed Piston Engine with two crank works.‬‏

It described a 2 cylinder, 4 piston, turbo charged motor. Big HP in a little package, with
very good mileage.


I was talking about this:

Watch "Opposed Piston Opposed Cylinder Engine" Video at Engineering TV


It’s called OPOC (Opposed Piston Opposed Cylinder), and it’s a turbocharged two-stroke, two-cylinder, with four pistons, two in each cylinder, that will run on gasoline, diesel or ethanol. The two pistons, inside a single cylinder, pump toward and away from each other, thus allowing a cycle to be completed twice as quickly as a conventional engine while balancing it's own loads.
The heavy lifting for this unconventional concept was performed Prof. Peter Hofbauer. During his 20 years at VW, Hofbauer headed up, among other things, development of VW’s first diesel engine and the VR6.
The OPOC has been in development for several years, and the company claims it’s 30 percent lighter, one quarter the size and achieves 50 percent better fuel economy than a conventional turbo diesel engine.
They’re predicting 100 MPG in a conventional car.
 
Last edited: