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Can you really believe this? 1,000 miles per charge and 96 mph?

...."And while ZPM is also licensed to build MDI’s two-seater OneCAT economy model (the one headed for India) and three-seat MiniCAT (like a SmartForTwo without the gas), the New Paltz, N.Y., startup is aiming bigger: Company officials want to make the first air-powered car to hit U.S. roads a $17,800, 75-hp equivalent, six-seat modified version of MDI’s CityCAT (pictured above) that, thanks to an even more radical engine, is said to travel as far as 1000 miles at up to 96 mph with each tiny fill-up....."

Click for more:
http://collectionofauto.blogspot.com/2008/08/air-powered-car-coming-to-us-in-2009-to.html
 

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Can you really believe this? 1,000 miles per charge and 96 mph?

...."And while ZPM is also licensed to build MDI’s two-seater OneCAT economy model (the one headed for India) and three-seat MiniCAT (like a SmartForTwo without the gas), the New Paltz, N.Y., startup is aiming bigger: Company officials want to make the first air-powered car to hit U.S. roads a $17,800, 75-hp equivalent, six-seat modified version of MDI’s CityCAT (pictured above) that, thanks to an even more radical engine, is said to travel as far as 1000 miles at up to 96 mph with each tiny fill-up....."

Click for more:
http://collectionofauto.blogspot.com/2008/08/air-powered-car-coming-to-us-in-2009-to.html



You forgot to include this from the article:


“I want to stress that these are estimates, and that we’ll know soon more precisely from our engineers,” ZPM spokesman Kevin Haydon told PM, “but a vehicle with one tank of air and, say, 8 gal. of either conventional petrol, ethanol or biofuel could hit between 800 and 1000 miles.”


This is basically a hot gas engine, same as an ICE. Do you really think these new air/hot gas engines are going to be anywhere near as efficient as a modern day ICE? No way.

Expect this car to be a miserable failure both technically and from a marketing perspective. The owner must fill the car with compressed air at extremely high pressures (no infrastructure exists) AND gasoline.

Here is the real killer... The car needs compressed air to run! Thus, you can't just go to the gas station and fill up with gas after the charge is spent, like you do with the Volt. You must also fill up with compressed air! There is no difference with having a BEV or a hydrogen car. There is no existing infrastructure!

If some people claim that the car can run using only gas then the air motor must be as robust and efficient as the latest modern ICE AND work a stand-a-lone air motor. Anyone betting this would be a very cheap motor? Ha!

Complete failure! This is scam! Do not invest! Wait to see the prototype! You will never see it being verified by a 3rd party!
 

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I find the claims by ZPM to be misleading - "up to" and "as far as" are weasel phrases.

I don't buy the whole "charge the air tank" scheme because of thermodynamic constraints.

However, I think there are good reasons to expect that the air engine running off pure gasoline (call it an External Combustion Engine - ECE;)) will be more efficient than an ICE. A precharge is not necessary, because burning the gas in a separate combustion chamber creates its own pressure.

Some thoughts about why you can't just assume that an ICE is better:

1) Air bearings have lower friction & better wear characteristics.

2) Engine will actually cool the combustion exhaust somewhat as it is decompressed.

3) Engine can operate in reverse to achieve regenerative braking. Heat of compression is recovered during decompression.

800 miles on 8 gallons is 100mpg, and I actually believe this is possible with a 1900 lb weight. I think there is a good chance that an air car will win the automotive X-prize, which would surely increase awareness of this technology.
 

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The mileage benefits could be real if people don't use gas powered air compressors to fill up their tanks. I'll be keeping an eye on this one.
 

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I find the claims by ZPM to be misleading - "up to" and "as far as" are weasel phrases.

I don't buy the whole "charge the air tank" scheme because of thermodynamic constraints.

However, I think there are good reasons to expect that the air engine running off pure gasoline (call it an External Combustion Engine - ECE;)) will be more efficient than an ICE. A precharge is not necessary, because burning the gas in a separate combustion chamber creates its own pressure.

Some thoughts about why you can't just assume that an ICE is better:

1) Air bearings have lower friction & better wear characteristics.

2) Engine will actually cool the combustion exhaust somewhat as it is decompressed.

3) Engine can operate in reverse to achieve regenerative braking. Heat of compression is recovered during decompression.

800 miles on 8 gallons is 100mpg, and I actually believe this is possible with a 1900 lb weight. I think there is a good chance that an air car will win the automotive X-prize, which would surely increase awareness of this technology.



Joshua, you bring up some good points. Let's look at each one closely.

1) Air bearing? I think those went out the window as soon as the motor had to burn gasoline. This engine will now run extremely hot. If it must run compressed air always, how do you overcome the lack of high pressure compressed air infrastructure?

2) This is a valid point. It will be interesting to see just how much cooler it runs. However, remember that a lot of heat energy was lost during the compression of the air. Thus, the whole efficiency cycle from the losses in compression the air to the actual burning of the fuel must be taken into account. You have to compare two complete energy cycles:

A) Compress air (lose a lot of heat energy), transfer to a tank, expand the air and burn gasoline to expand the air further. Take this heated and expanded air into an expansion chamber to convert to rotary motion, exhaust expanded and cooled air to atmosphere.

B) Compare to a turbo ICE. The turbo is powered from wasted exhaust gases, compressed air is used to help combustion and expansion, complete gas burning inside a controlled combustion chamber, exhaust expanded and cooled air to the atmosphere.

Thus, you are competing against a turbo ICE that has been under development for many decades! If burning the gas externally or running air bearing would make an engine more efficient, mechanical engineers would have already included them in the design. Thus, your hope of gaining thermal efficiency over the complete energy cycle is probably misguided.

I see the only real possible benefit of using compressed air is for a poor man's battery. Maybe you get a few miles out of your garage running on compressed air before you have to switch to running an efficient ICE. I personally think the electric motor and battery will be cheaper and better over the long run but the compressed air tank has the advantage of being simple and relatively cheap (for very short ranges - the cost goes up exponentially as more range is needed).

However, when all the costs and benefits are looked at the simple plug in hybrid will come out cheaper. You can also do a simple electric hybrid using lead acid batteries that would also give you a good couple of miles while being inexpensive.

In summary, compressed air does not hold a lot of energy for a given volume and energy wise it’s a very inefficient process. Finally, there is no infrastructure for high pressure compressed air. These systems will be very expensive. Will the market adopt the Air Car as the next mode of transportation and thus justify the infrastructure costs? I doubt it.
 

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The infrastructure could easily be added. The precursor for it is electricity. Really, it's more of an infrastructure base than hydrogen.
 

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A year from launch? Where's the working prototype? What are the real world performance figures that are being collected right now on test tracks and highways? What's that? They don't have any of this? Get back to us when you do!! So easy to put up a website and make a claim.
 

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The infrastructure could easily be added. The precursor for it is electricity. Really, it's more of an infrastructure base than hydrogen.


Easily? Can you please give us your 5 step plan. Please include how many stations, the cost of each bay, what percentage penetration is needed so the car can safely make it anywhere, manufacturing lead times for the hundreds of thousands of high pressure compressors, etc.

I don't think the word easy should be used anytime we talk about transitioning the US transportation infrastructure. What are you smoking?
 

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Easily? Can you please give us your 5 step plan. Please include how many stations, the cost of each bay, what percentage penetration is needed so the car can safely make it anywhere, manufacturing lead times for the hundreds of thousands of high pressure compressors, etc.

I don't think the word easy should be used anytime we talk about transitioning the US transportation infrastructure. What are you smoking?
You'd could make that argument about any form of alternate vehicle. I say "easily" only as far as electrical energy can be converted to compressed air with a machine. The cost would certainly beat out hydrogen infrastructure. Most service stations have a compressor. They're easy to install. All this would be is setting a higher quality compressor. Anyone with electricity at their house could do the same.

The issue with aircars isn't infrastructure. It's energy density. Argue that. No need to trashtalk it on all points.
 

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The issue with aircars isn't infrastructure. It's energy density. Argue that. No need to trashtalk it on all points.
You also have to take into account the energy required to compress the air. How much electricity would it actually take to run super-powered air compressors all day at gas stations all over the country? I'm not trash talking, just curious.
 

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You also have to take into account the energy required to compress the air. How much electricity would it actually take to run super-powered air compressors all day at gas stations all over the country? I'm not trash talking, just curious.



Mr. Bogey, Just because we are debating your arguments does not mean we are trash talking. You just said something crazy and I wanted to point out your level of craziness. Yes, the question is the infrastructure. How can you say it's not? It will cost in the billions of dollars and 10s of years to complete. It's a huge point. You can try to marginalize it all you want but that does not change the fact that it would require an enormous amount of capital and commitment to complete to make the Air Car viable. I'm not trash talking when I say the Air Car is a scam. I truly believe it. I honestly feel it will never compete against the simple and well proven turbo ICE or any form of plug-in hybrid with similar specifications (vehicle weight and range).


And you say no need to trash talk on all points. The devil is in the details. If we all decide to go one path and not think of every little point do think it would come out well? I don't want 10 Republicans sitting at a table and all agreeing with each other. That's how they got the drill-our-way-out idea! If you trash talk all the details you see how easily the concept falls apart. I'm going to continue to trash talk every last detail until the best options are left. Air Cars can be kept up on the shelf.
 

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1) Air bearing? I think those went out the window as soon as the motor had to burn gasoline. This engine will now run extremely hot. If it must run compressed air always, how do you overcome the lack of high pressure compressed air infrastructure?
I'm an electrical engineer, but I stayed at a Holiday Inn a while back, so I'm going to say that air bearings are possible.

It won't run as hot as an ICE, because it is more efficient than an ICE, and because the action of the decompression cools the gas.

I'm talking about an External Combustion Engine (ECE). The gasoline is burned outside the air engine, and the exhaust pressure is used to run the engine. So no, you don't need a compressed air infrastructure. It just gets 100mpg. And wins the X-prize.
 

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Debating my argumments?

You're just laughing them off without any further thought. To whine about the infrastructure needed to support this car when any non-gas/diesel is starting out with the same handicap is absurd. Someone could easily belittle electric cars as being as laborous to implement because not everyone has 20A 220V service to their carport or accessible from their service station.

But it's ridiculous to say it's take decades to get compressors into service stations.
 

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Discussion Starter #14
I'm talking about an External Combustion Engine (ECE). The gasoline is burned outside the air engine, and the exhaust pressure is used to run the engine. So no, you don't need a compressed air infrastructure. It just gets 100mpg. And wins the X-prize.
An excellent example of a very efficient ECE is the Stirling Engine. This has been modified by Stirling Energy Systems and used in solar dishes, and so far is one of the most efficient method of converting sunlight into electrical energy, averaging more than 32% efficiency, and the levelized cost of capacity is about $0.30/Watt.

Well, I agree with most of you. Until they produce one REAL prototype vehicle that will undergo third party testing, and publish the results in credible engineering or scientific internationally refereed journal, with results that included energy consumption of compressors to power up a given volume of tank and pressure, we should be able to evaluate their claims.

Wikipedia has analytical thermodynamic formulas that describe the energy involved compressing and decompressing air given its initial and final psychrometric and other properties. It is not straightforward though, as you have to assume isothermal or adiabatic paths, neither of which can be controlled precisely when compressing the air with ordinary compressors. That is the only problem that has prevented me from doing the energy balance calculations. Either that, I would assume isothermal path, and then that would mean cooling the air while compressed to achieve the isothermal calc, which would be unrealistically introducing another energy expenditure for the sake of simplifying the calculation. So I can settle for empirical methods of energy balance measurements, unless someone here could point out engineering or scientific studies done on this subject.
 

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But it's ridiculous to say it's take decades to get compressors into service stations.
After much discussion with our friend Texas, we came to a consensus that compressing gas isn't efficient enough because the heat of compression is left at the service station. So I don't think compressing a large air tank makes sense.

But the car I'm talking about would do just fine with a smaller air tank - just big enough to do a good job at regen.
 

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After much discussion with our friend Texas, we came to a consensus that compressing gas isn't efficient enough because the heat of compression is left at the service station. So I don't think compressing a large air tank makes sense.

But the car I'm talking about would do just fine with a smaller air tank - just big enough to do a good job at regen.


I guess we will just have to wait to evaluate the final Air Car prototype. I think it will become very clear then. There are a few companies that have been working on getting a workable car out for a long time and they are determined to get the job done. I wish them the best of luck in recovering all the time and money they put into this venture.

Even if you get the best and most efficient ECE you have to add the efficiency losses from compressing the air in the first place. These are not small losses. At least the turbo ICE is using some of the wasted heat energy to spin the turbo. I have thought about it, did the calculations, looked at the energy balances, etc. I'm convinced but I understand that people will actually have to see the car and compare it to what is already out there. Thus, I say we will wait and see. I look forward to it because it will be a learning opportunity for all of us.

Mr. Bogey, I'm not whining about the infrastructure. I am also not putting it to a disadvantage when comparing it to other options. I also feel it will take over 10 years to transition to BEVs or hydrogen cars. Our short-term options are few. We have biofuels that run using existing infrastructure, plug-in hybrids that can use the grid for some of the range and existing infrastructure when needed. Not too many other good short-term options.

You see Mr. Bogey, you have no experience in manufacturing and thus have no idea what a huge job we are talking about. You feel you can call up Ace Air Compressors and order up the required compressors to be install later in the year. You think we can convert our 117,000 (as of 2002) plus gas stations in a year or two? If you actually made an attempt to draw up a project plan and included realistic milestones like ramping up of manufacturing facilities, pulling together installation crews and companies, ordering the massive amounts of needed materials, getting the proper permits, handling the capital transactions, etc. you would quickly come to the conclusion that this is indeed a massive job.

America is huge and it's infrastructure is massive. You are simply naive to think this is an easy job. I'm sorry you don't understand but talk to any experienced manufacturing guy or construction company and they will set you straight. I know you cannot listen to me but listen to them. You say it's ridiculous but it is in fact reality. Try this, call up a manufacturer of high pressure compressors (10,000 psi) and ask them how much it would cost and how long would it take to put one in each service station in America. They will hang up on you, laugh or ask if you are on drugs. It's really that big.

Now if America decided that this was the Manhattan project and it was war time we could get this done much faster. However, it would cost untold amounts of cash (credit in our case) and would be a massive project.

Just for an idea of the scale of the project think about going down to your local gas station and putting in this complex compressor system. All the building facilities, utilities, enclosures, customer facilities, etc. Just the planning, the permits, inspections, the workers, coordinating that project, etc. and multiply that project 117,000 times! It boggles the mind.

That is why we need to sweat out every detail when we are talking about what our next transportation infrastructure is going to be. Hydrogen? Quick charge BEVs? Biofuels? Compressed Air Cars <cough>, etc. The one we choose is going to cost our country a lot of time and capital. If we get it wrong it's a huge mistake. That's a gross understatement.
 

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Mr. Bogey, I'm not whining about the infrastructure. I am also not putting it to a disadvantage when comparing it to other options.
Which is then followed by whining and dismissiveness about the infrastructure needed.
 

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Which is then followed by whining and dismissiveness about the infrastructure needed.


Is that your retort? When a person cannot effectively argue their position they usually resort to marginalizing. Saying that I'm "whining" when I'm simply educating you is childish and makes you look foolish. How about we stick with facts and reality. If you don't like what you hear then counter with an effective argument. If you cannot come up with one well maybe it's time to just be quiet until you can. I look forward to your constructive "whining". At least it will give me something to debate.
 
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