Naked Science Forum

Non Life Sciences => Technology => Topic started by: Atomic-S on 15/06/2008 07:04:43

Title: Why is this air-powered car not available in the US?
Post by: Atomic-S on 15/06/2008 07:04:43


Subject: Air Powered Car
 
http://www.popularmechanics.com/automotive/new_cars/4217016.html (Popular Mechanics Article on this car)
 
This is the same company which-a few months back-invented a car that costs only $2500 new.��BUT�it's not available in the USA.  Why is it that a gasless vehicle that eliminates the reason to buy oil from foreign countries hasn't nipped the minds of US manufacturers? How bad can this be for anybody, anywhere in the world -- except for foreign oil?

will just DEMAND this technology in the USA

Title: Re: Why is this air-powered car not available in the US?
Post by: LeeE on 18/06/2008 19:42:22

It probably doesn't meet U.S. crash test requirements.

The air-powered car is similar in some ways to the fireless steam locomotives that used to be used in some gas works - they too had a reservoir to hold steam generated at a remote power station.

Title: Why is this air-powered car not available in the US?
Post by: lyner on 19/06/2008 11:04:08

Filling would be a scary business. I would go into the bunker for the first few times.
To refill quickly, the air would have to be already compressed / pre-cooled in a storage tank. 'Pumping up' from atmospheric pressure would generate an awful lot of heat  at the time. This heat, whenever generated,  would 'leak out' in time and represents a  loss of efficiency - you are dealing with isothermal rather than adiabatic processes; this is something which most heat engines try to avoid.
To be honest, I would prefer my stored energy to be in the form of Chemical Bonds.

Title: Why is this air-powered car not available in the US?
Post by: Bored chemist on 19/06/2008 19:12:10

"340 liters of air at 4350 psi."
That's 295 bar pressure or 30MPa and the volume is aboy 0.3 cubic metres.
That's about 10MJ of stored energy if I have done the maths right.
Diesel stores about 34 MJ per litre (based on reading a bottle of cooking oil).

So the "fuel" tank holds the equivalent of about a third of a litre of diesel fuel.

How close together are the refilling stations?
Also where does the energy to compress the air come from? If it's fossil fuel then this doesn't solve the problem, it just moves it.

Title: Why is this air-powered car not available in the US?
Post by: lyner on 19/06/2008 23:26:53

You will probably be able to buy one on ebay before too long, if they come on the market.