The compressed Air car has been mentioned by Popular Mechanics and Green News as being the true car of tomorrow, with the same mileage and zero emissions as a fuel-cell car without the dangers currently associated with hydrogen.
[edit] Technology
Air Cars are powered by air engines, fuelled by compressed air, which stored in a tank under high pressure such as 30 MPa (4500 psi or 300 bar). The tank is likely to be made of carbon-fiber in order to reduce its weight while achieving the necessary strength. Instead of mixing fuel with air and burning it to drive pistons with hot expanding gases; Air cars use the expansion of compressed air to drive their pistons. All four major manufactures who are developing CAT cars have designed safety features into their containers as opposed to hydrogen's issues of damage and danger involved in high-impact crashes. Air, on it's own, is also non-flammable. Though no company has yet demonstrated the effectiveness of an imploding (ZAP) engine vs a quick-release (MDI) standard, and other safety designs; it is expected that large-scale production may lead specific governments to set their own standards. It was reported on Discovery's Beyond Tomorrow that on its own carbon-fiber is brittle and splits; but creates no shrapnel.
[edit] Emission output
Air cars are emission free at the 'tailpipe', but their compressed air tanks are recharged using (typically) electric compressors and the electricity for such compressors will usually come from fossil fuels via power stations, so unless the electricity comes from a renewable source Air Cars will still cause emissions of Greenhouse gass. However emissions would be relocated from city streets to remote smokestacks (of course a solar and/or wind recharging system can be installed in one's home, therefore eliminating the dependence of grid consumption of energy).
[edit] Criticism
Compressed air is a heavy way of storing fuel, 300l air at 300bar only amounts to about 12kWh (the equivalent of 1.4 liter (0.37 gallons) of gasoline). While gasoline or diesel fuel tank have the same amount of energy per litre of fuel from the first to the last litre, compressed air tanks rely on the pressure in the tank, and that falls as air is drawn off. Air Car technologies would move Co2 emissions off city streets but still require energy and cause CO2 emissions elsewhere.
[edit] Models
Overoptimistic reports of impending production date back to at least May 1999. The Air Car made its public debut in South Africa in 2002,[1] and was predicted to be in production "within six months" in January 2004.[2] Various companies are investing in the research and development of Air Cars including Mitsubishi of Japan and:
[edit] EngineAir
EngineAir, an Australian company, is developing a rotary engine powered by compressed air.[3][4] The Energine Corporation is a company that delivers fully-assembled cars running on a hybrid compressed air and electric engine. These cars are more precisely named pneumatic-hybrid electric vehicles.[5] A similar (but only for braking energy recovery) concept using a pneumatic accumulator in a largely hydraulic system has been developed by U.S. government research laboratories and may soon be produced for delivery van use.[citation needed]
[edit] K'Airmobiles
K'Airmobiles has presented two running prototypes of VPA (Vehicles with Pneumatic Assistance). Their leaders now seek to gain the means of developing several projects of urban or leisure VPP (Vehicles with Pneumatic Propulsion). K'Airmobiles propose a different technology with their VPP (Vehicles with Pneumatic Propulsion), which may allow a reasonable range, generally with compressed air tanks of about 50L-100L/3000 psi capacity only.
[edit] MDI
Moteur Developpement International (MDI) claims is intending to launch cars with a range of 200-300km (124-186 miles), thereby making it applicable for most daily car use. As of May 2007 a range of just over seven km (five miles) has been demonstrated. "Refuelling" the tanks with compressed air takes 3-4 minutes; therefore, the cars will also be able to be used for longer journeys. In addition to the compressed air refuelling option, the car has a built-in air compressor that can plug into any standard outlet and refill the tanks in 4 hours. The cars have a maximum speed of 220 km/hour (136mph)[citation needed].
The CityCat model will clock out at 68 mph (110 km/hour) with a driving range of 125 miles (200 km).[6]
The MDI MiniCAT
There are two MDI models in development using Compressed Air Technology: the three-seater MiniCAT for local commuting and the six-seater CityCAT for longer distances.
MDI has been accused of multi-level marketing, in that the company is interested in selling turnkey factories. They have been promoting these factories since at least 2001, but apparently none have yet been built. In 2001, a Swedish journalist investigated a company promoting the car in Sweden, but he came to the conclusion that it was a scam. He met many people who were ready to sell him shares in a manufacturing company, but none had actually driven the car.[7]
[edit] Tata
As of May 2007 Tata Motors of India planned to launch an Air car in 2008.[8]
[edit] ZAP
Pictures/slides of the ZAP Motors concept were displayed at the 2007 Chicago Auto Show showing two models in testing; a two seat or a five seat hatch-back.
[edit] See also
Air engine
Compressed air energy storage
Compressed air vehicles
Pneumatics
Moteur Developpement International
Eolo Car
[edit] External links
K'Airmobiles - The ecologic compressed air vehicles
K'Airmobiles - Les véhicules écologiques à air comprimé
MDI's Air Car website
MDI's Official website
Fan Site and Portal to the various air-car websites
Energine, a South Korean company developing Pneumatic Hybrid Electric Car
Theaircar.se., A Swedish info site about the MDI car (Swedish language)
ZevCat Inc., A US company that would like to sell MDI Vehicles
ZAP Auto International
[edit] News articles
Popular Mechanics on Tata's Air Car
Tata's Air Car
Tata's Air Car
BBC Article
Second BBC Article
Korean Air Car/Electric Vehicle
Beyond Tomorrow Episode about the Vehicle
The Science Channel Video Report
MSNBC article
Short video report on YouTube
A Video Clip test drive of MDI Air Car
[edit] References
^ Kevin Bonsor (2005-10-25). How Air-Powered Cars Will Work. HowStuffWorks. Retrieved on 2006-05-25.
^ Robyn Curnow (2004-01-11). Gone with the wind. The Sunday Times (UK). Retrieved on 2006-05-25.
^ http://www.gizmag.com/go/3185/
^ [1]
^ http://www.patentstorm.us/patents/7028482.html[2]
^ source: 05-31-2007 http://green.yahoo.com/index.php?q=node/315
^ Norbert Andersson (2001-05-16). Luftdriven bil mest bluff (In Swedish). Retrieved on 2007-06-06.
^ World's First Air-Powered Car: Zero Emissions by Next Summer. Popular Mechanics (2007-05-28). Retrieved on 2007-05-28.
