Compressed air-powered cars like the AirPod pictured above are conceptually cool. But the real-world efficiency of using compressed air to move a vehicle just isn't worth is, says a new study published in the latest issue of Environmental Research Letters.
The main problem, one of the study's authors told AutoblogGreen, is that compressed air holds less than one percent of the energy of gasoline and, given the amount of electricity it takes to compress the air, "the air car's carbon footprint is more than twice as large as that of a gasoline car." Battery-powered cars are also more efficient than compressed air cars, the researchers found. Two possible ways to use compressed air technology in vehicles would be to combine it with a gasoline engine in a either a pneumatic–combustion hybrid or an air engine hybrid set-up, the authors say.
You can read the entire article, called "Economic and Environmental Evaluation of Compressed-Air Cars," in the October-December 2009 issue of Environmental Research Letters. Thanks to Andrew P. for the tip!
Potentially related: the company behind the AirPod has missed several deadlines to bring the car to market, as you can see in the comments to this post.
[Source: Environmental Research Letters, NYTimes]