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The Air Car Preps for Market

Some still question the vehicle's chances of success, despite a boost from India.

By Tyler Hamilton

Wednesday, January 16, 2008

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A French-designed car that's propelled by compressed air and claims speeds of more than 60 miles per hour is expected to go into commercial production as early as this summer, although skeptics of the technology aren't holding their breath.

Air car: MDI says that its MiniCat compressed-air car (above) can reach speeds of up to 100 miles per hour and has a range of up to 125 miles.
Credit: Motor Development International

Using compressed air, they argue, may mean zero tailpipe emissions, but it's unlikely to provide enough range or speed to appeal to the masses, particularly in North America. "Compressed air does not contain much energy--that's the killer," says Larry Rinek, senior research analyst for automotive technologies at consultancy Frost & Sullivan. "This is more a nice garage project for a Popular Science subscriber."

But the dream lives on. Motor Development International (MDI), based near Nice, France, has developed several prototypes of its Compressed Air Technology (CAT) car since its first engine was created 14 years ago. Now company founder Guy Negre, an aeronautics engineer who developed a high-performance racing engine for Formula 1 in the late 1980s, is counting on India's largest carmaker, Tata Motors, to bring his highly anticipated Air Car to market later this year.

The Air Car was supposed to hit the streets years ago, but its release always seems just around the corner. MDI announced in 2002 that the cars would be used to replace taxis in Mexico City, but nothing resulted.

Tata's involvement this time around, combined with the fact that oil recently hit $100 a barrel, could change the game. India's largest automaker announced last February that it had struck a deal with MDI to further develop and refine Negre's compressed-air engine technology, with the intention of producing and selling the emission-free cars in India. It has since been reported that Tata invested nearly $30 million in MDI as part of the agreement.

"The recent manufacturing push is in response to the contract that MDI signed with Tata," confirmed Kevin Haydon, a spokesman for Zero Pollution Motors, based in New Paltz, NY. He says that the company plans to manufacture CAT vehicles in parts of the United States around 2010, through a license with MDI.

Story continues below

Zero Pollution has even entered the car in the multicity Automotive X Prize competition, where in 2009 more than 30 teams--including electric carmakers Tesla Motors, Phoenix Motorcars, and Malcolm Bricklin's Visionary Vehicles--will compete on the fuel efficiency of their vehicle designs.

The Air Car may do better than fuel-cell cars, but experts say that using grid power to charge a battery-powered electric vehicle is much more efficient than using electricity to compress and store the same amount of energy in a tank. "The main problem is that air gets hot when you compress it, so much of the energy input goes into raising the temperature of the air as you try to raise the pressure," explains Doug Nelson, a professor of mechanical engineering and an expert on advanced vehicle systems at Virginia Polytechnic Institute.

Comments

  • >>> the only mid-term solution is the cellular-like electric car >>>
    .

    the zero-emissions/zero-fuel air-compressed car is a dream that (I hope) may become commercial

    to-day's electric cars are more realistic and already are commercial products, but still have a lo range

    then, the only mid-term solution could be the "cellphoneCAR":

    http://www.gaetanomarano.it/articles/033cellphoneCAR.html

    .
    Rate this comment: 12345

    Gaetano Mara...
    01/16/2008
    Posts:91
    Avg Rating:
    2/5
    • Re: >>> the only mid-term solution is the cellular-like electric car >>>
      http://www.gaetanomarano.it/articles/033cellphoneCAR.html

      Cellphone car? Why not a UN treaty for global fleets of GPS controlled, dual energy, compressed air vehicles, buildings, and buoys - so a network of Weather Radars and Satellites can set the temperature of your compressed air exhaust to whatever it needs to be (37* Fahrenheit - 97* Fahrenheit) to reinforce the Hadley - Ferrel - Polar air cell boundaries, and weather patterns needed? Would you like to do this with me? No?

      Meanwhile, perhaps a Christmass toy of a cell phone controlled fleet of miniature compressed air vehicles you can program to create "weather patterns" in a nice tent, that can also be used for camping [^] might be a good idea, no?

      Google Translation: English » Russian, Spanish, etc.
      Rate this comment: 12345

      Weather Cont...
      05/03/2009
      Posts:2
  • What about cold climates?
    It is mentioned that this engine is using the ambient temperature to warm the air, and power the 2nd stroke. This may work well in India and other tropical countries. But how about the winters of North America?
    Rate this comment: 12345

    gabrielg01
    01/16/2008
    Posts:361
    Avg Rating:
    3/5
    • Re: What about cold climates?
      MDI now has a dual energy model:   http://www.mdi.lu/english/oneflowair.php

      When used in the compressed air only mode the exhaust is cold: 37* Fahrenheit who once read.

      When used in the "external combustion" engine mode, the exhaust can be as hot as 120* Fahrenheit who once read.

      So, in the context of a UN Treaty to build and drive global fleets of compressed air vehicles whose emissions temperatures are controlled by a weather radar and weather satellite "cloud computing" network (Ha, ha.), the dual energy compressed air car is not only transportation, it's weather control, and air purification.

      "'Ah, Dad, do I have to?" "Until you can pay the $20 bonus we get for meeting our driving requirement, yes. Now 'Hop to it!' - before I have to touch my iWatch to mute the alarm, or do you want me to deduct that %5 charge from your allowance right now?" "I'm goin', I'm goin',"
      Rate this comment: 12345

      Weather Cont...
      05/03/2009
      Posts:2
  • Air Car engine.
    What type of engine is used for this machine? (Technology). Is a piston based engine?

    P.S.
    The idea for a “air car” is very SMART, and has some advantages (refill of the car can’t be made “at home”, the “fuel” for this car must be bougth like you buy oil for standard machines)
    Electric cars don’t have this “advantages” because electricity is something that everyone has at home.
    Rate this comment: 12345

    Handshake
    01/16/2008
    Posts:15
    Avg Rating:
    3/5
    • Re: Air Car engine.
      I pondered this idea over the past few years and it seems that the normal piston engine could serve also as a compressor during regenerative braking, pumping air back into the tank.  Conventional piston engines are little more than steam engines which use a volatile liquid to expand air when it's ignited. This makes for a very nice hybrid technology.
      I love the part about getting power on the upstroke as well as the downstroke!
      Rate this comment: 12345

      kearns
      01/16/2008
      Posts:28
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      4/5
    • Re: Air Car engine.
      Actually. It has the ability to be plugged in and an on board sort of "alternator" can refill the tanks in about 4 hours. There is also options for a cold weather package.
      Rate this comment: 12345

      andraon
      05/05/2008
      Posts:3
      Avg Rating:
      5/5
  • Right Technology, Wrong Paradigm for North America?
    I am not so sure that this technology is a nonstarter for today's North American car market, as the article implies. I think it may indeed be useful within a slightly different context.

    This article explores the potential for vehicles powered solely by compressed air and hybrid vehicles using compressed air supplemented by a gasoline engine. An additional area of interest, however, is whether compressed air technology is useful in a hybrid vehicle where a conventional fuel engine is the primary power source and the compressed air serves as the supplementary power source. In other words, it would be very much akin to today's hybrid cars, except that compressed air is used as the dynamic energy storage medium as opposed to electric batteries. The big benefit is potential cost savings over the gas-electric hybrid approach.

    Research has shown the value of this concept. For more information, see: http://www.futurepundit.com/archives/001552.html
    Rate this comment: 12345

    wf
    01/16/2008
    Posts:14
    Avg Rating:
    5/5
    • Re: Right Technology, Wrong Paradigm for North America?
      Right technology:  I have studied and taught changing paradigms for years.  You are so right that the AIR CAR requires a major shift in North Americas paradigm.  However you must admit with the cost of OIL as it is we MUST shift something.  It is extreemly difficult to make people change or break old paradigms, but it is now time to start.  The AIR CAR is by far the best thing to be developed since electricity, and the internal combustion engine.  We MUST give it a chance.
      Rate this comment: 12345

      panamablaine
      05/20/2008
      Posts:1
      Avg Rating:
      4/5
  • Crash Unworthy
    Article fails to mention that car is very very light weight.

    Go strip 75% of the weight out your current car and you'll improve mileage, just don't expect to live through a crash.
    Rate this comment: 12345

    scottaye
    01/16/2008
    Posts:4
    Avg Rating:
    4/5
    • Re: Crash Unworthy
      Of course, it looks like they expect people to drive more slowly than is typical of gas-powered cards. In a place where everyone's driving one of these things, there might be the ancillary benefit of fewer/less severe accidents.
      Rate this comment: 12345

      Monsterboy
      01/17/2008
      Posts:72
      Avg Rating:
      4/5
      • Re: Crash Unworthy
        That's why they like to start selling those cars in India. Have you ever been in any big city in India?
        The streets are always packed and the average vehicle speed is just a little faster than a bicycle/scooter.
        Rate this comment: 12345

        mcberta2
        01/18/2008
        Posts:4
        Avg Rating:
        3/5
  • Retrofitting and larger airtank
    What would happen if you increased the air tank capacity and rigged the widget (engine) up to a flywheel to be used to generate electricity? Can this be done? By tying the solution to a solar panel for air charging, there may be a market for alternate power back up for homes or even power for rural environments.

    Spin up the flywheel - disengage the airtank - recharge with solar and repeat as needed.
    Rate this comment: 12345

    mkogrady
    01/17/2008
    Posts:168
    Avg Rating:
    3/5
    • Re: Retrofitting and larger airtank
      ...add a wind turbine to the roof so it generates electricty when it moves , and if all else fails have low paid imigrant worker push the car around . simple . could this be done ????
      Rate this comment: 12345

      DJTal
      01/20/2008
      Posts:124
      Avg Rating:
      3/5
  • Liquid Air
    I always like to take a problem to it's logical extremes. Consider this, compress the air till we get liquid air (the compressed air in the car as is proposed would have to remain hot, retaining it's energy, to work efficiently).

    If we were to fill up with liquid air, the fill process would be little more difficult than with current liquid fuels, actually, a bit safer since there is no chance for fire or environmental pollution (consider the tanker disaster in Oakland).

    As we "run" the car, we'd pass ambient air through a heat exchanger, forcing the air through a phase transition and heating it up as much as possible with ambient conditions -- leaving cooled air in our wake. We would, in effect, be satisfying the first law of thermodynamics, to it's most fundamental implementation; we'd be propelling the car with ambient heat, reducing the temperature of the air in the wake of the car.

    As juvenile as Ayn Rand (in Atlas Shrugged) was with her, "extracting electricity from the air", in effect, we kind of can do something similar.

    Now, we just need to build a frost-less heat exchanger!
    Rate this comment: 12345

    dgholstein
    01/20/2008
    Posts:2
    Avg Rating:
    5/5
    • Re: Liquid Air
      I agree; We at darlap have designed what we think is an elegant design combining a series of hollow disks containing liquid air with ambient air moved between them by the boundary layer factor and spinning at a rate sufficient to strip the frost. Since we have this unit free to spin, we use the reaction turbine principle for a "hero's engine".  The centrifugal force also (with the help of a pressure cap on the liquid air tank) serves as a charging pump.  We restrict the outlet of this ambient "warming" air resulting in a temperature rise adding to efficiency.  There may be something of interest to you on our website; darlap.com We have lost our funding possibilities while waiting for the IRS to approve our "not-for-profit" status.  Apparently private research foundations are quite rare, and noone seems to have a slot for cryogenic energy storage.
      bill michaels; founder/president DARLAP NFP
      Rate this comment: 12345

      bill michael...
      08/03/2008
      Posts:1
      Avg Rating:
      5/5
  • Efficiency
    In all these discussions on so-called "green" energy solutions, no-one talks about efficiency!
    Efficiency is the make-or-break of any energy technology.

    I see this process as an energy transport system consisting of 3 phases: Compressing the air, transporting the air, and recovering the energy.

    Air compressors are notoriously inefficient. as the article states, a lot of energy is wasted as heat.

    The air must be transported to the place where it is dispensed. Compressed air has very little energy per unit weight (c.f. fuel, for example), so therefore this part of the process must be inefficient.

    Air motors are just as inefficient as compressors (being essentially the reverse process).

    If it uses grid power to compress the air in the first place, then it simply moves the pollution to another place (the power station), and as it's inefficient, it produces more pollution than an equivalent fuel-powered car would.

    Junk.
    Rate this comment: 12345

    zeddy08
    01/21/2008
    Posts:1
    Avg Rating:
    3/5
    • Re: Efficiency
      The low efficiency of compressing and expanding air is due to using isentropic compression and expansion. Much of the energy goes into temperature change. A pure isothermal would, neglecting friction, be totally efficient - but the best so far is about 95%, and isn't practical for transportation.
      MDIs car has about half the efficiency of a PHEV or BEV (electrical part only), range is about the same, first cost is half. There aren't resource constraints. I'd like an E-volt, but for commuting 90 miles daily round trip, first cost is more critical. $20,000 would cover years of trips, more than are likely, especially if I can talk the boss into providing the electricity while I'm at work!  ;-))
      The dual fuel range extending feature is be nice also.
      Rate this comment: 12345

      DDHv
      07/05/2008
      Posts:1
      Avg Rating:
      3/5
    • Re: Efficiency
      Efficiency is not as important as cost. Gasoline is a very inefficient fuel and yet a very practical one. If the fuel is cheap and available, the efficiency can be low, and the technology can still be viable.

      Moreover, this garbage about moving the pollution to a different location has been debunked many times. While coal-fired power plants are dirty, only half of US electricity is generated that way, making EVs cleaner overall than gasoline; and emerging energy technologies are only going to make electricity generation cleaner.
      Rate this comment: 12345

      Tysto
      04/07/2009
      Posts:24
      Avg Rating:
      4/5
  • The Air Car is real, videos on at http://www.youtube.com/user/CATvolution
    Guy Negre of MDI Air Car engine that runs on compressed air. Emissions are only filtered air that's cleaner than outside air. 300 bars of pressure in carbon-fibre & kevlar air tanks. Car can travel at 110 km/hr and has a 150 km driving range. Refilling can be done by plugging in at home or at a special high-pressure air station. Dual-energy models use small amounts of bio-fuels that can extend the range to over 1400 kms. Pollution free vehicle that produces zero emissions. When the car stops at traffic lights, the engine stops so no energy is lost because there's no idling. See the videos on http://www.youtube.com/user/CATvolution or go to http://www.catvolution.com for more information.
    Rate this comment: 12345

    catvolution
    02/25/2008
    Posts:1
    Avg Rating:
    5/5
  • Marketing the CAT cars in NA
    I think that marketing these cars in North America would in fact be successful. The price of gas is so outrageously high that most people cannot afford to fill their tanks on a regular basis. With the cost of filling up the tank of one of these "air cars" at approximately 2-3 dollars, I think that people would immeadietly jump on the bandwagon so to speak and buy a car. Additionally, with this new financial crisis, people will be in even more desparate financial states than before. I believe that money is a big enough motivator to get people to buy these CAT technology cars.
    Rate this comment: 12345

    peaceluvr
    10/04/2008
    Posts:1
    Avg Rating:
    3/5
  • run air car on Natural Gas
    Use compressed Nat Gas and you’ve got two energy sources, the high preasure energy and the flammable fuel.

    Lately it is possible to build a combustion engine with all computer controlled valves. This sort of control provides the engine the ability to burn lean like a Civic or heavy like a Corvette as well as operate as an air compressor or an air motor.

    With this new engine technology a car is able to run on air or combustible fuel (Compressed Nat Gas). The car could decompress some Nat Gas to start up and then combust the decompressed Nat Gas. Break to a stop in compressor mode while filing an air tank that you can later use to start the car rolling.

    The engine doesn't need a starter motor and the battery isn't used to start the car.
    Rate this comment: 12345

    luckin
    11/20/2008
    Posts:1
    Avg Rating:
    2/5
  • [no subject]
    It seems as though quite many posters become confused about the air car claims. They seems to think that just because air can power tools like the gmc parts and move a car around for a few miles that it can be used as a substitute for the vehicles we currently drive.
    Rate this comment: 12345

    MickeyFouse
    04/29/2009
    Posts:47
    Avg Rating:
    1/5

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