AIR CAR. Motors run on compressed air.

[Bill in Houston]

Originally Posted by RickyD

even so if you ran a small diesel generator in the back to recharge the air your miles could become huge. In the video I first posted they claim LA to NY on one tank of gas

But, you still can't get something for nothing. Running a generator and a compressor and an air motor is waaayyyyy less efficient than just running a diesel engine...

[GasSavers_RickyD]

Originally Posted by Bill in Houston

But, you still can't get something for nothing. Running a generator and a compressor and an air motor is waaayyyyy less efficient than just running a diesel engine...

ummmmm errrrrrrrr ummmmmmmm

how so. The producers of this engine claim LA to NY on ONE tank of gas, supposidly to run the generator..

I dont know how anything can be more efficent then that.

[88HF]

Does it even use gas? I thought the on-board compressor only plugged in for a 4 hour fill-up? One tank of gas is deceiving. If you were carrying another engine you couldn't achieve similar statistics same with adding a gas tank. Large compressors to compress air make sense because larger engines are more efficient such as lose of huge ships. Perhaps if air were compressed many times more than necessary and transported to stations where it was metered into car tanks. But moving around highly compressed anything is dangerous. They are just moving the emissions from the automobile to a centralized location which could (in theory) be dealt with more easily. Enough compressed air could move anything, but its all in the safety, weight, efficiency.

[GasSavers_Ryland]

"one tank of gas" I met a guy once who hauled 50 gallons of bio-diesel with him on a road 2,000 mile road trip, he made the whole trip on "one tank" one of the big reasons that air cars are not widly used is that they are basicly a steam engine running off a tank of air, it's not really anything fancy or new, altho they are lighter weight and more efficent, but just like the frost on the out side of a propane tank, the air tanks get extreamly cold, and the engine gets extreamly cold, when this happens the compressed air shrinks so your range drops, try that in wisconsin in the winter and your air car is going to be a solid block of ice with an empty tank, in india and south africa when they make these it's not so much of an issue.
but still, you have to remember, air is just an energy storage system, just like hydrogen, it's takes alot of energy to get it in to it's useable form, I was remineded today of the hydrogen problem, how it takes something like 60% of the energy in hydrogen to compress it to a presure where you could get enough of it in a vehicle.

[cfg83]

RickyD -

Ok, here's another youtube video on the same subject :

http://www.youtube.com/watch?v=gFbKINlXzRk

It *claims* to be pretty cheap, even at an air pump station they are designing, something like $3+ dollars for 100 miles.

It definitely is an urban sub-freeway car, and it has to be light, so I think in it's current form it would be limited to 25 MPH, aka the Zenn around town electric golf-carts.

I do like that it is using caron fiber to lower weight.

Question : How much emissions from the air pump for each 100 mile tank?

Question : How does it compare to batteries, aka another energy storage system?

CarloSW2

[rvanengen]

I was having a similar discussion with a friend about this vehicle...based on this site:

http://www.popularmechanics.com/auto...s/4217016.html

1) range of 125 miles
2) carbon-fiber tanks with 340 liters of air at 4350 psi
3) gives us an air consumption rate of 2.72 L / mile

Assuming the performance numbers are accurate, we started to do some math:

1) 1 ft? = 28.3168 L meaning that the car would have a capacity of appx 12 cf of air.

2) A run-of-the-mill scuba compressor (ie. http://www.americanairworks.com/aircompressor.html -- American Airworks Fast 35 -- Portable AC95535 - Honda 5.5 HP Gas
$3090 ) rated at 3.5 CFM @ 4500psi would recharge the cars air tanks in about 3 1/2 minutes using gasoline.

3) If we assume 1 hour / gallon running at 100% output (in generator form, the Dewalt Heavy-Duty 2900 Watt Gas Generator - DG2900 will run 11.3 hours at 50% output on 3 gallons) and a fuel tank of 3 gallons, the generator should be able to recharge 630 CF of air @ 4500psi in 3 hours.

4) The 630 CF of air should translate to appx 17830 L of high pressure air.

5) This should give a theoretical range of about 6555 miles on 3 gallons of gasoline, or about 2185 miles per gallon. Seems a bit high to me...so lets increase the generators fuel consumption by a factor of 10x. You will need 30 gallons for the same trip giving you 218.5 MPG. Seems pretty good.

My only question for such a long trip is: at what speed is that range of 125 miles achieved? If it is at 30 MPH, that's a LOOONG trip!!

Perhaps we were up a bit late, and I admit that simple math often trips me up...are we missing something here? Sounds like it is vastly more efficient to have a small compressor running at 100% for short periods and then stretch the resulting stored energy out over a longer period of time using an engine that is designed for that purpose. ??

[mrmad]

I don't have the time (or really the desire right now) to do the calculations, but if we assume 100% efficiency, meaning all the calories from burning 3 gallons of gas are used to propel the car, it seems to me that 2185mpg is defying the laws of physics.

I think we are missing something here. I also have to use the few functioing brain cells I have left to remain employed, so back to work.

[rvanengen]

Originally Posted by mrmad

I don't have the time (or really the desire right now) to do the calculations, but if we assume 100% efficiency, meaning all the calories from burning 3 gallons of gas are used to propel the car, it seems to me that 2185mpg is defying the laws of physics.

I think we are missing something here. I also have to use the few functioing brain cells I have left to remain employed, so back to work.

Well...all the calories from burning 3 gallons is NOT being used to propel the car...it is ONLY being used to compress 630 CF of air. I would assume that it is VERY inefficient as far as % of calories are going to actual air compression.

It seems they are saying that their use of the compressed air is highly efficient in moving the vehicle. Not sure either...and I am also trying to keep earning money. (back to modding bank software)

[mrmad]

Originally Posted by rvanengen

Well...all the calories from burning 3 gallons is NOT being used to propel the car...it is ONLY being used to compress 630 CF of air. I would assume that it is VERY inefficient as far as % of calories are going to actual air compression.

It seems they are saying that their use of the compressed air is highly efficient in moving the vehicle. Not sure either...and I am also trying to keep earning money. (back to modding bank software)

Whether it's running an aircompressor or not, ultimately, it is propelling the car, and I don't think there's enough calories in 3 gallons of gas to move a car 6555 miles. Compressed air may be an efficient way of moving a car, I just find it a little hard to believe it's that efficient.

If you are modding bank software, anyway to pad my account?

[rvanengen]

Originally Posted by mrmad

If you are modding bank software, anyway to pad my account?

I suppose we could leftpad with a decimal point and a bunch of zeroes.

Now...where did I leave my Ferrari keys? Gotta get back to the villa before the cleaning staff knows I am gone.