no electric cars, no hydrogen cars, how about air?

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Less infrastructure shock, how about an intercity car using air? Move the pollution out of the city and reduce the need for oil and the cost of maintenance and regulation.
 
Originally Posted By: turtlevette
Compressed air? How is that better than electric?



+1

Why not extend the range with a small gas powered air compressor?
 
If you watch the video they have a model that does that.


Originally Posted By: RichardS
Originally Posted By: turtlevette
Compressed air? How is that better than electric?



+1

Why not extend the range with a small gas powered air compressor?
 
Compressing air is a very inefficient way to store energy. When air is compressed it heats up. As the heat is dissipated to the environment the pressure in the tank drops. That is an energy loss you can't recover.
 
Why this might be better than electric. The speed controller that the air does not have is cheaper and lasts longer (lol). Same with all that electric stuff to say nothing of the benefits of not having to haul a heavy battery or recycling it later.
 
Originally Posted By: OneEyeJack
Why this might be better than electric. The speed controller that the air does not have is cheaper and lasts longer (lol). Same with all that electric stuff to say nothing of the benefits of not having to haul a heavy battery or recycling it later.


It is not better than electric, the energy density of compressed air is even lower than a lead-acid battery (which is dismal compared to a hydrocarbon fuel). Modern lithium batteries are much more efficient.

Plus compressing the air takes a lot of energy.
 
Originally Posted By: OneEyeJack
how about an intercity car using air?

How about meat-powered?
 
Originally Posted By: Tegger
How about meat-powered?


With a suitable oxidizer sure. I've been to rocket launches where people have used salami as a fuel in their hybrid motors.
 
Originally Posted By: OneEyeJack
If you watch the video they have a model that does that.


Originally Posted By: RichardS
Originally Posted By: turtlevette
Compressed air? How is that better than electric?



+1

Why not extend the range with a small gas powered air compressor?


I fear I was being sarcastic. Unless the compressed air is some sort of by-product, I find little sense in using electricity to compress air, transport it, store it, and then use it to power a vehicle when you could just do that with the electricity.

Todays lead acid batteries are profitable to recycle, and most new batteries contain 60-80% recycled lead based on EPA estimates from 2011.

Tesla has a successful closed loop recycling program in North America, so it's not an impossible feat.
 
Originally Posted By: kschachn
Originally Posted By: Tegger
How about meat-powered?


With a suitable oxidizer sure. I've been to rocket launches where people have used salami as a fuel in their hybrid motors.


all them there darned nitrates!
 
Originally Posted By: CT8
How does the air get compressed?


In the areas that hydrogen mines are found, there's usually vast untapped reserves of pressurised air that can be drilled for, tapped, and trucked to where needed.
 
Originally Posted By: kschachn

It is not better than electric, the energy density of compressed air is even lower than a lead-acid battery (which is dismal compared to a hydrocarbon fuel). Modern lithium batteries are much more efficient.

Plus compressing the air takes a lot of energy.


Take the cylinders at a foot diameter and 10 feet long, and at the advertised 4,300psi (29MPa ???)

Adiabatic expansion of this gas to atmospheric yields 36MJ of energy...about equivalent to a litre of gasoline.

Given that there's a point in the depressurisation of the tank that there's no pressure to drive the cylinders, then much less.

Anyone who has pumped up a bike tyre knows how hot things get during compression, all of which is wasted energy when you let it cool back down in storage cylinders before decanting...compressing it to 4,300psi takes lots of intercooling, and therefore more energy wasted could easily be 3-5 times the amount of energy that you get out the other end.

Yet another imaginative boondoggle that will suck up naive investors, and through legislators, taxpayers money.

(as an aside, "refilling" from a gaseous phase cylinder is a pain...take a working tank of volume 1, and a storage tank of volume 10...connect the empty tank to the storage tank, and both tanks end up at 90% pressure...you don't fill the empty tank, and are stuck with less pressure for the next fillup. When we get hydrogen deliveries at 3,000psi, the tanker leaves at nearly 1,000 for the trip home)
 
Low energy density.

The concept of sitting on a very high pressure tank of air in an accident is not amusing. They'd probably shovel your remains into a couple of buckets.
 
Here's the somewhat more "sensible" logical extension to the premise.

A liquid nitrogen (well liquid air) car, where super cold liquid air expands and provides motive power.

/http://www.lowcarbonfutures.org/sites/default/files/LAIR%20Highway%20FINAL.pdf

But again, that looks like a product of surplus supply looking to make a compelling argument for it's utilisation using environment as a driver.

The split cycle Ricardo is pretty interesting...except no-one found it interesting.

https://bobistheoilguy.com/forums/ubbthr...eff#Post4279215

An extension of the split rankine cycle that seems to have been abandoned, taking the compressor stage from a GT, compressing air into salt caverns off peak, then using the compressed air into the turbine stage of a GT for double the power in peak times.
 
Originally Posted By: kschachn
Originally Posted By: Tegger
How about meat-powered?


With a suitable oxidizer sure. I've been to rocket launches where people have used salami as a fuel in their hybrid motors.


No; meat-powered, like this...
Fortified-Bicycle-Invincible-Theft-Proof-Bike-10.jpg
 
I have a better idea. Why not fit a car with massive rear tires and small skinny front and let the gravity do all the work? it will be always going downhill!
 
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