106 mpg 'air car' creates buzz, questions

[Hum]

(CNN) -- You've heard of hybrids, electric cars and vehicles that can run on vegetable oil. But of all the contenders in the quest to produce the ultimate fuel-efficient car, this could be the first one to let you say, "fill it up with air."

That's the idea behind the compressed air car, which backers say could achieve a fuel economy of 106 miles per gallon.

Plenty of skepticism exists, but with many Americans trying to escape sticker shock at the gas pump, the concept is generating buzz.

The technology has been the focus of MDI, a European company founded in 1991 by a French inventor and former race car engineer.

New York-based Zero Pollution Motors is the first firm to obtain a license from MDI to produce the cars in the United States, pledging to deliver the first models in 2010 at a price tag of less than $18,000.

The concept is similar to how a locomotive works, except compressed air -- not steam -- moves the engine's pistons, said Shiva Vencat, vice president of MDI and CEO of Zero Pollution Motors.

The six-seater planned for the U.S. market would be able to reach speeds of more than 90 mph and have a range of more than 800 miles thanks to a dual energy engine, Vencat said.

The design calls for one or more tanks of compressed air under the car's floor, as well as a tank holding at least 8 gallons of fuel.

Whether the engine uses just air or both air and fuel would depend on how fast the car is going. It would run purely on compressed air at speeds less than 35 mph, Vencat said.

Since the car could only go a short distance when using just air, fuel is needed to get the full range, he explained.

"Above 35 mph, there is an external combustion system, which is basically a heater that uses a little bit of gasoline or biofuel or ethanol or vegetable oil that will heat the air," Vencat said.

"Heating the air increases its volume, and by increasing its volume, it increases [the car's] range. That's why with one gallon of gasoline or its equivalent we are able to make over 100 mpg."

Vencat said an on-board compressor would refill the air tank while the car is running, or owners could refill it by plugging it into a power outlet for four hours.

Experts aren't sure Americans will be zipping around in air cars and getting 106 mpg, or more than twice the fuel economy of hybrid-electric vehicles such as the Toyota Prius.

It is possible to power a car with compressed air, but the mileage claim is "at the edge of possibility," said John Callister, director of the Harvey Kinzelberg Entrepreneurship in Engineering program at Cornell University's College of Engineering.

He noted that such dramatic fuel efficiency is associated with tiny experimental cars, not bigger mainstream ones.

"No one's really proven a six-seater passenger car [can get] any better than 75 miles to the gallon. So this would represent a big step forward," Callister said.

"They would have to prove that before they can throw rocks at the Prius."

Another expert expressed concern about the amount of energy it would take to generate the required air pressure: 4,500 pounds per square inch, or more than 120 times the pressure inside the tires of a typical four-door sedan.

"That is above what you normally find even in an industrial setting," said William Bulpitt, senior research engineer at the Georgia Institute of Technology's Strategic Energy Institute.

"That takes quite a compressor to do. ... It takes horsepower to compress the air up to that pressure."

If you count that energy, it's hard to believe the car would be that much more efficient than an electric vehicle, Callister said.

The compressed air car will get a chance to prove itself next year when it competes for the Automotive X Prize. The multimillion-dollar award will go to the team that "can win a stage race for clean, production-capable vehicles that exceed 100 mpg equivalent fuel economy," according to the X Prize Foundation.

The air-car concept has also drawn the interest of Tata Motors, India's largest automaker. The company announced an agreement with MDI last year to further develop and refine the technology.

However, the cars have yet to hit the streets in India or anywhere else.

"The project is under progress. We do not yet have any timeframe for launch," said Debasis Ray, the head of corporate communications for Tata Motors.

Only prototypes exist at this point, Vencat said.

The body of the car planned for the United States would be built with fiberglass and injected foam. The chassis, composed of aluminum rods, would be glued together, not welded.

The design allows the car to be as light as possible, Vencat said.

For anyone who has doubts about its safety, he insisted computer simulations show that the vehicle would pass crash tests and meet all U.S. safety standards.

"Do you think somebody would actually put millions of dollars into making a car that will not pass safety regulations? There's no point in doing that," Vencat said.

Callister pointed out that there haven't been any lightweight, 100-plus mpg cars to pass crash tests but said it could be done through a "very clever design" of a lightweight frame.

A good prototype could dispel many of the doubts about the compressed air car, he added.

"I don't think we should discount this advance if it happens," Callister said.

source

[bdsams Veteran]

Compressed air scares me more than hydrogen. WHen the compressed air tank is at max capacity its a bomb

[John S. Veteran]

Interesting concept...their website is here: http://www.theaircar.com/

[MR_Candyman]

Compressed air scares me more than hydrogen. WHen the compressed air tank is at max capacity its a bomb

I don't see why. It's rather hard to make an air tank go boom. It's actually easier to make an oxygen tank go boom.

[Yusuf M. Veteran]

I don't see why. It's rather hard to make an air tank go boom. It's actually easier to make an oxygen tank go boom.

Same here. Air is simply a mixture of gases (mostly nitrogen which is inert). This company could rock the automotive industry if they pull through with their pledge. I guess we'll have to wait and see.

[Osiris]

oh well no more dangerous than gas really. I mean lets be honest if anything in a car goes "boom" its never going to be pretty....Unless its in GTA, than its the shizz

[theyarecomingforyou]

Well, it's good to see any company trying to make serious progress. It's absolutely pathetic that with today's technology we have vehicles that are barely more efficient in the consumer range than 40yrs ago - in fact the trend over the past decade was for much larger, inefficient vehicles. It's doubtful this vehicle will get to the upper end of its projected efficiency - especially not with typical usage or fully loaded - but anything over 60mpg would be reasonable, with anything over 80mpg impressive. I'm just surprised the technology hasn't been bought up and buried.

[wst50]

I like this technology a lot. If it takes off I'd like to try modifying it to do high performance, at least for my 'air car'. I feel that, unlike electricity, it is not a crime against mtoring, as you still have pistons going :D (or a turbine maybe? Oooh)

[SoCalledChaos]

Compressed air scares me more than hydrogen. WHen the compressed air tank is at max capacity its a bomb

And so are the batteries in the current Hybrids.. whats your point.

[revvo]

I don't care how efficient it is, it looks like ****!

Why must every (or most) "earth friendly" cars look absurd and futuristic?

[Yelreve]

When it is compressed 120 times the pressure the of a tyre then it could definately explode with a devistating amount of force, there would be no flames but if you were in the car you would be toast ;) Anyone remember Jaws...

[goji]

"No one's really proven a six-seater passenger car [can get] any better than 75 miles to the gallon...

What? I'll settle on a 75 mpg vehicle and be happy to!!

[+virtorio MVC]

Why is it so hard for people/companies behind these kinds of cars to design something you wouldn't actually be embarrassed to be seen driving?

[Andrew Lyle Global Moderator]

When it is compressed 120 times the pressure the of a tyre then it could definately explode with a devistating amount of force, there would be no flames but if you were in the car you would be toast ;) Anyone remember Jaws...

umm mythbusted :p

The airtanks are designed to take twice the amount of force used in it. and I am sure a blast shield would be installed if that was the occasion.

Also, if you get a hole in the tank, it turns into a rocket, not a bomb.

[PricklyPoo]

Why is it so hard for people/companies behind these kinds of cars to design something you wouldn't actually be embarrassed to be seen driving?

My question as well.

[Kane]

There's been a video on Youtube about this for ages. Same company in this video I think.

To the person in this thread that mentioned the compressed air containers exploding, they are made of carbon fibre and just split instead of exploding.

[chrisj1968]

umm mythbusted :p

The airtanks are designed to take twice the amount of force used in it. and I am sure a blast shield would be installed if that was the occasion.

Also, if you get a hole in the tank, it turns into a rocket, not a bomb.

Hehe, is that then considered turbo? ;)