new air powered car

Simply beautiful.

If, as the movie shows, the overall environmental price of compressing the air, is as low as hinted here, that's got to be worth a lot of R & D effort on a global scale.

That Australian rotary piston is inspiring. Great design, if a bit reminiscent if the old German Wankel design from the nineteen-fifties. Rotary desiugn is much more efficient that 90 degrees kinetic conversion of conventional design, having a lot of torque lost into heat, while stressing the crank-shaft

If an air compressor to refuel this vehicle is only 25% efficient. then how can the air car be efficient?

You have answered your own question, at a first obvious glance it isn't. If you delve down into the operation and underlying physics and energy conversion math behind these compressed air vehicles, it turns out that it in fact they are hopelessly inefficient.

Have a look at previous threads on compressed air cars (including the French scam).

http://cr4.globalspec.com/blogentry/2851/The-Air-Car

http://cr4.globalspec.com/thread/19747/Pneumatic-AIR-Motor

http://cr4.globalspec.com/thread/13103/Car-that-runs-on-compressed-air-is-the-car-of-the-future

etc.

I know the world is desperately hanging out for something new and cheap but none of these b...s gonna make it as far as I'm concerned.

Currently you can seat there from morning to night and keep thinking but it's all f...hopeless, not to mention how noisy it is.

The fruit and vegetable warehouse in Melbourne is ok due to its cleanliness and for its nearby refuelling but surely you do not expect to run anything with it over long distances.

As the air pressure drops in the tank it also faces the same problem as its electric counter part - loosing its power unlike petrol that has it until the last drop of fuel.

Having an extra combustion engine on board to produce compressed air in the fuel tank/s then the current hybrid method is a lot better answer.

So, happy dreaming!

Simply put they can't. Too low energy conversion efficiency, energy density in storage, and heavy storage. Also safety in accidents. Much better would be CO2, but then that would have to be released to the environment, not good.

HOWEVER, with the right setup, a propane or CNG (compressed natural gas) vehicle could use the NOW BEING WASTED tank pressure to give on-demand acceleration etc, before being burned in the engine. This would require maybe some sort of drive with expansion cylinders (in other words similar to the air motor) before being fed to the engine. And the heat required for its expansion (now taken from engine cooling water) could be supplemental air conditioning. Or maybe the easiest would be to use it to drive accessories via a small turbine? Also it could work nice with a hybrid hydraulic - THESE have MANY advantages over hybrid electrics, mostly in reduced components and NO BATTERY.

All these are only ideas, which would need to be investigated, as they apparently have NOT done when promoting compessed air. jesse.blenn@lift-tecno.com

Jesse

Hi,

We all know that compressing air as a source of stored energy is inefficient but it is Financial efficiency they are talking about. The French vans look similar to various ultra lightweight vehicles we see running around Europe. They get by on something like 3 or 4 litres of petrol per 100km. Current fuel prices here of around 1€/litre so we are comparing ( assuming the figures in the video are correct €4/100km for petrol against 4$Aus or approx €2/200km for similar vehicles.

For market trucks, or local delivery/ inner city vehicles it looks a viable project. Compare it with the traditional electric milk delivery vehicles used in the UK and I think it has to be on a good footing as they carry a massive load of traction cells, which in turn have a limited life of about 1500 cycles. The air tanks will have a virtually unlimited life. DC electric motor versus air motor? I think the dc motor will be a bit less maintenance but not a lot.

I think we will see them on the streets of Europe and Asia but highly unlikely in the US unless a congestion tax or something similar gives them a boost.

Regards

Chas

Thanks for your opinion but I am confused about your meaning of "financial efficiency " for in the USA I refer to profitability…. Simply stated is there any profit to compress air for fuel then to directly fuel the vehicle

tom

Hi Tom,

Not real efficiency at all, Financial viability. If my rough sums are correct it is a worthwhile project here in europe as out "gas" prices are rather higher than yours.

regards

chas

I did see something about this before, I love the concept really, but it was explained that you had to have huge tanks on the vehicle. This would hinder the efficiency rating I assume, as well as cargo capacity no ? Perhaps it should be used for certain types of vehicles, in more of a localized manner in the time being at least. Hauling compressed air seems to be counterproductive.

But I will ask everyone a different question.

Combustion engines aren't efficient at all, and the only reason they were viable at any time in history was because the FUEL WAS CHEAP !!! When the gas crisis hit here in the 70's, my father went from a caddy to a Datsun because gas went over a dollar ! Look at us now !

So, I ask, how important is it for anyone now, just how efficient some of these new concepts are, when the only thing most people care about is how cheap they are to "refuel" or maintain ?

So, I ask, how important is it for anyone now, just how efficient some of these new concepts are, when the only thing most people care about is how cheap they are to "refuel" or maintain ?

Have a look at the previous threads on such things as the compressed air-powered car and other concepts. Efficiency is one thing and fuel cost is another but the fuel has to come from somewhere. Electricity ain't free in cost or fuel, and compressed air requires some means to compress it. Even solar and wind turbines require fuel and resources to make them and they only have a finite life span. When assessing new technologies (or old ones again) one must always look at the "whole picture" and take into account the costs in materials, energy, infrastructure, additional equipment necessary, government subsidies hiding the true cost (which is passed on to the consumer in other ways), etc. Only then can you get a clear picture of just how viable a technology is.

Right.

So, is it worth global research and development (which also has it's cost), in your opinion, given it's ecological attributes?

- Should we go hybrid with on-board air-compressors like done with electric ?

- Is current compressed-air cannisters adequate for minimal range of operation ?

- What would be viable infrastructure in terms of production, distribution, safety ?

Good to know, and was never presented here.

I have to admit I was fascinated at first.

Hi Jackofalltrades,

Your energy density figures are worthless inasmuch as they are not what the end use looks at. Try selling any vehicle (except a space vehicle) with those figures and you will go broke very quickly.

What matters to the end user, especially if they a commercial concern, is the running cost.

I personally hate these vehicles but, frankly, they would probably make good financial sense for my business. 95% of our work is carried out within 5km of our office/ workshop, so range would not be an issue. As electricians our payload would not be very high, perhaps 100kg. Fuel costs in Europe are high, typically 1€/litre.

Now compare that with costs of €0.15/kWh, add in functions such as lower insurance costs (they're slow), low road tax due to low power, Congestion charges in major cities are often waived or reduced for non contaminating vehicles, they may come in the light vehicle category which means the driver doesn't need a licence, which means the company can hire cheaper labour and lastly, fewer parts to fail.

The overall efficiency of compressed air may only be 10%, or perhaps less since they must be at a higher pressure than 8 bar, but it doesn't matter, the user will only look at the daily cost or perhaps lifetime cost.

What would be your best guess at the sums if you were to rate it on that basis?

Kind Regards

Chas

Your energy density figures are worthless inasmuch as they are not what the end use looks at.

Mentioning the energy density figures was just a very short, simple (but not very detailed) way of explaining the subject. Like trying to explain the theory of the universe in one sentence. I kept it simple for a reason.

Have a look at the numerous previous posts and threads on the subject of air cars, the links to the main discussions are in post #2 above.

I do not think I need to go into a more detailed discussion again as myself and others have spent ages writing detailed explanations before. Go and have a look at these first, perhaps there is a point we have missed previously.

What would be your best guess at the sums if you were to rate it on that basis?

You would honestly probably be better off with an efficient gas vehicle (perhaps CNG or LPG). However, local regulations, taxes, incentives, etc may make one of the existing available electric vehicles viable for you but I don't know if they would be of use as a "work wagon" due to limited cargo space in most models (same with compressed air vehicles). Electric vehicles have their advantages and flaws but I haven't seen any compressed air vehicle or compressed air technology under development that can even come close to them. If you want a vehicle with a short range you can connect up to the grid and recharge, a compressed air vehicle MAY be more viable than an electric car, but you are really only trading advantages and disadvantages of the two technologies. In your particular case I think that an electric vehicle would still win, even taking into account the battery cost.