Amazing Air Car from India

[mvadventure]

I've seen threads on air vehicles before but here is one that has come into being on a commercial scale albeit not for us unless you live in India. At first glance I see great potential and despite the obvious problems of having that much compressed air onboard in the event of a collision or other impact situation it seems better, cheaper and more efficient than electric. http://weeksmd.com/?p=862
Mike

 

[diver]

I like to see all these neet ideas

 

[cerewa]

Fill it up at home with a compressor powered directly by the wind?

 

[paultrafalgar]

Did you see this update?
http://www.popularmechanics.com/automotive/new_cars/4251491.html?series=19

 

[JRP3]

I've seen threads on air vehicles before but here is one that has come into being on a commercial scale albeit not for us unless you live in India. At first glance I see great potential and despite the obvious problems of having that much compressed air onboard in the event of a collision or other impact situation it seems better, cheaper and more efficient than electric. http://weeksmd.com/?p=862
Mike

Sorry but that "air car" is a car powered by electricity. How do you think the air is compressed? I still see it as an inefficient use of electric power.

 

[paultrafalgar]

You've missed the point. Yes, the compressor is using electricity to compress the air, but the electricity can be generated by renewable methods like wind, solar, wave, nuclear etc. It doesn't have to be fossil fuels, whereas conventional petrol or diesel cars do and thus dump CO2 into the atmosphere. Transport accounts for a large slice of the CO2 emissions causing global warming. "Electric" (including air-driven) transport is essential in the future.

 

[JRP3]

I think you've missed the point. Compressed air is an inefficient use of electricity however it's generated, and air compressors and air motors have more moving parts to wear out than the single moving part of an electric motor. Plus you now have the added joy of oil changes on the compressor and your air motor. Air cars are a step in the wrong direction, simply another form of ICE. Fast charge long life batteries are here, now, and the only need is for the price to drop, which can happen with increased production and automation, as well as subsidies and tax breaks.

 

[paultrafalgar]

I think the important thing is power-density per $. I agree that using electricity to compress gas and then using that compressed gas to generate motion has to be less efficient than using a battery to store the energy, but as they say here:

http://quasiturbine.promci.qc.ca/QTVehiculePneumatique.html

-----------------------
"COMPRESSED AIR VEHICLE

Pneumatic systems have a big advantage: they are cheap and don't require impractically expensive battery maintenance. A 40kg 25 cubic meter compressed air cylinder the same size as the steel types used in natural gas vehicles can store 4 kw-hr of energy. Assuming (conservatively) that 50% can be recovered, we have a real world density of 2kw-hr/40kg = 50 watt hours per kg.

This is much better than the best lead acid lead acid batteries which can achieve 50 watt hours
only by 100% discharge: something that cuts battery life to only a dozen or so cycles.
The power to weight ratio of compressed air systems is quite high: Higher than most electric system."
-----------------------

Yes, you are going to point out that Lithium batteries are better, but: 1) is there enough Lithium to power all the cars on the planet and 2) How long will it be before it's cheap enough to compete with a compressed air system?

 

[JRP3]

Unfortunately the real world performance of air cars doesn't support that. The only ones demonstrated are underpowered short range golf carts. I'd rather have a 50 mile range full sized EV with real performance than a "100 mile" mini air car with anemic acceleration.
There is plenty of lithium available for the foreseeable future, plus lithium can be recycled from old batteries. NiMH batteries as used in the EV1 and RAV4EV can also be used, once Cheveron's patents expire, or a lawsuit is brought against them for holding onto a technology without developing it themselves. Plus there are other battery technologies being developed.

 

[jerryt]

Unfortunately the real world performance of air cars doesn't support that. The only ones demonstrated are underpowered short range golf carts. I'd rather have a 50 mile range full sized EV with real performance than a "100 mile" mini air car with anemic acceleration.

Each to his own of course. Personally I'd prefer a Bugatti Riyale with an oil well in my back yard but my budget and logic believes that one or maybe several $12-$15k anemic air car(s) with adequate range makes more sense than a $100k batt powered SUV.

 

[slayer]

For one thing that the air powered car will have is that it is very clean power, no disposal of batteries could be recharged at home thru electric, no emmission like gaz powered, and with time and new thinking it will gain in strength ...i use air powered tool every day ...my boss has got air power tools that have 30 + years... they are making air power impact wrench that has 1000 lb in and more... they requires 2 or 3 drops of oil too keep the quality at it s best and that s all.

 

[slayer]

Plus if the first one i see from india is already for under 13, 000 $ is capable of 125 miles in on tank and going up to 68 mph and can refill in less than 5 minutes by electric or gas or many other way powered compressor ...it is already very respectable.

 

[JRP3]

Each to his own of course. Personally I'd prefer a Bugatti Riyale with an oil well in my back yard but my budget and logic believes that one or maybe several $12-$15k anemic air car(s) with adequate range makes more sense than a $100k batt powered SUV.

That's a ridiculous comparison. You can do a basic lead acid conversion for $10k that will outperform the aircar and get 40-50 mile range which is quite adequate for most people. For $100K I'd take a Tesla over a Bugatti any day since I wouldn't need the oil well.
Plus, let's not forget, the range of the air car has not been demonstrated.

 

[mvadventure]

Some reasonable arguments have been presented, pro and con. If we think about it for a minute though the air car from India with its built in compressor is, despite the fact there is a long history of air vehicle attempts, emerging technology. I too use air tools although not on a daily basis. A 3/8" wrench can sit in a drawer for months, a drop or two of light weight oil and a good compressor it runs all day without compaint. My 1/2" wrench has more torque than my arms do for continued use and has been trouble free for years.

Granted air tools and air cars are different technologies but while comparing an air car with an electric car may be a reasonable comparison, comparing them with an ICE vehicle with current technologies is an unfair situation. ICE vehicles have been around more than 100 years and have been, due to the abundance of oil, refined many times over for both power and economy. Given a chance I believe a generation or two of air cars may very well be a viable alternative. A hybrid air car, one with a small ICE to power the compressor in order to increase range may be the ideal vehicle.

IMHO and I accept I may be mistaken, an air car with a small ICE such as a 5HP Honda engine for backup compressor use would be a much more practicle vehicle. Sitting on the side of the road for a half hour if need be waiting for the tanks to charge would be a whole lot better than sitting on the side of the road with a dead battery regardless of battery technology. The same engine of course could be used for recharging the battery and the convenience would have to be measured in the time it takes tol recharge sufficiently to get home.

For the moment my bride or I tend to wind up sitting in a running car with the AC on while waiting on other family members, sometimes for an hour or more. Sitting in an automobile with AC in the Florida sun is tolerable, take away the AC and it simply cannot be done with our "newfound" dependance on AC. (my first factory AC car was a 1974 Ford and while I bought a couple without since then it's still been almost thirty years) To me the convenience and comfort of AC is as important as fuel economy or alternate vehicle range. Whether an electric or air powered vehicle can provide such creature comforts is yet to be demonstrated, it does take HP to provide AC.

In the meantime, much to the chagrin and amazement of my friends, I enjoy my electric bike.

Mike

 

[slayer]

this is a quote from a guy who says he s got a ph d in physics ... so i guess we could assume the tank does or can deliver 125 miles range on tanks alone ....meaning if you add a ice motor or a electric motor you could add to the range in one trip...


Thus electric cars of whatever nature are inherently superior to gas or diesel cars from an efficiency and 'green' perspective. This car is another form of electric car, only instead of batteries it has air-tanks and instead of electric motors it has pneumatic motors. Air devices are amazing. Most of the controls on Boeing 707 airplanes were run by pneumatics, there were very few electronics on those early aircraft. Most people today would be in complete disbelief if they knew how many systems on a 707 were run solely by air pressure. Anyway back to the topic. Some math: Based upon a poster from last years' Pop Mech comments, Mil Std 1522A indeed has a chart that shows how much energy is stored at a given pressure and a given volume. Obviously we cannot get more energy out than we store. So how much energy is there stored in 340 liters of air at 4351 psi? Well 340 liters is 12 cubic feet. I'll round up (to use the mil-std-1522A table) to 5,000 psi. That table shows there is about 1.5 million foot-pounds of energy stored in one cubic foot of 5,000 psi air. The tanks hold 12 cubic feet of air, so there are 18 MILLION foot-pounds of energy stored in the tanks, impressive!! How far can 18 million foot-pounds take someone? Well they claim the car is 75-HP equivalent. 1 HP is 550 foot-pounds of energy per second. So 18 million divided by 550 is 32,727 seconds for which 1 horsepower could be delivered from those tanks. But they say its a 75-HP equivalent, so divide 32,727 by 75 and you get 436 seconds of that power which could be delivered, just over 7 minutes. Now granted, you rarely would be operating a car at 75-hp, most of the times you're travelling at fixed speeds and you just have to offset road friction and air resistance. I don't have values for what those drag and resistance amounts might be. Would it take 5 HP to overcome friction and air resistance when traveling at 65 mph? If so, then the car could deliver 5 HP for 109 minutes, which would be close to the advertised 125-mile capability (at ~65 mph)

 

[slayer]

ok probably in the very best condition with no hills and highway driving but the point is i was trying to figure if it was 125 miles range with the aid of a secondary power...seems not

 

[paultrafalgar]

If the sceptics here are correct, then the inventors and backers of the Tata air car are lunatics soon to become bankrupt. We shall soon see!

 

[JRP3]

this is a quote from a guy who says he s got a ph d in physics ... so i guess we could assume the tank does or can deliver 125 miles range on tanks alone ...... I don't have values for what those drag and resistance amounts might be. Would it take 5 HP to overcome friction and air resistance when traveling at 65 mph? If so, then the car could deliver 5 HP for 109 minutes, which would be close to the advertised 125-mile capability (at ~65 mph)

It could also take 6-10hp to keep the car moving at 65, which would really reduce the range. Not to mention those low HP values only work if there is no acceleration involved, i.e. hills and stops, or a head wind. I still see their claimed performance figures as a stretch at best in real world driving, especially since this looks more like a city car and would be more likely driven in stop and go driving around town.

 

[slayer]

Ok yes probably in the very best conditions, no hills, highway driven but with those numbers you can assume it will deliver an average of 5hp for 109 minutes or 10 hp for a bit less than an hour ...it is still very respectable ...10 hp for an hour with air ...if you add a secondary power like 5hp ice engine or 5hp electric you could recharge on the go for those longer trip but how many time you need that much range...most of the time you would only need the air supply from the tank.

 

[JRP3]

So now you want to add another engine to the vehicle to add cost, complexity, and transfer losses? That's the problem with regular hybrids. To make an efficient vehicle pick one energy dense power source and stick with it. That's why BEV's have such great potential. I don't think compressed air will ever be able to achieve the needed energy density to compete with BEV's, and they can't match the simplicity of the single moving part in an electric motor. An air motor and compressor will need rebuilding way before an electric motor ever will.

 

[nomad85]

So now you want to add another engine to the vehicle to add cost, complexity, and transfer losses? That's the problem with regular hybrids. To make an efficient vehicle pick one energy dense power source and stick with it. That's why BEV's have such great potential. I don't think compressed air will ever be able to achieve the needed energy density to compete with BEV's, and they can't match the simplicity of the single moving part in an electric motor. An air motor and compressor will need rebuilding way before an electric motor ever will.

It's still pretty cool. Beats using gas... and buying batteries. If it works as well as they say it can, I'd certainly get one. Changing the oil on an air compressor is a once a year easy chore...

 

[TylerDurden]

If the sceptics here are correct, then the inventors and backers of the Tata air car are lunatics soon to become bankrupt.

Well, they did buy Jag and LandRover... :lol:

 

[docnjoj]

Interesting that its posted in a Psychiatric journal!
otherDoc

 

[paultrafalgar]

If the sceptics here are correct, then the inventors and backers of the Tata air car are lunatics soon to become bankrupt.

Well, they did buy Jag and LandRover... :lol:

Only to electrify them with compressed air! :lol:

 

[swbluto]

The running energy efficiency of an air car is almost guaranteed to be less due to thermal energy losses with the compression but the initial energy/money investment *might* be less than a battery setup(As it requires money to afford the supplies for a battery and much energy to create it) at a given range, I'd actually guesstimate much much less with a higher energy storage which is what most consumer drivers require. Too bad the ones I've heard were noisy but perhaps there are quieter ones out there.

Basically, with current technology, the initial investment might be much lower even though the running costs might be higher but I wouldn't guess that much higher. With the 3-5 year New car cycle most consumers engage in, the longterm costs would probably be cheaper with an air-car. Now only if those EESTOR super-capacitors materialized.