ABC/Yahoo is reporting on a concept by Peugeot/Citroen of a hybrid car running on gasoline and compressed air. They claim it will be cheaper than gas/electric hybrids. Want a Car That Gets 117 mpg? - Yahoo! News From the article: When it's not running on gasoline, it uses … the air. There would be a sturdy tank of compressed air in the floor or trunk, recharged by the engine or the brakes. Peugeot Citroen, the French automaker, has now shown off a prototype for such a system and claims on its website (in French) that it could start selling air-hybrid cars in Europe by 2016. The company, according to Europeannews reports, says that on local streets, the cars would mostly run on compressed air, cutting gasoline use - and costs - by as much as 80 percent. The technology would start in existing subcompact models, the company said, but soon expand to include vehicles of all sizes. I have to admit this is a new one on me.
I always thought the old Citroen's were ahead of their time. Do they still have that air suspension, where you could change a flat tire by just sticking a big block or piece of wood under the car with the suspension pumped all the way up and then just let the air out?
Compressed air is the most inefficient power distribution system, less than 10% efficient. Much much less at higher psi in the thousands. This is straightly vapor ware. http://www.cedengineering.com/upload/Compressed%20Air%20Energy%20Efficiency.pdf
The idea of using compressed gas has been around for along time - unfortunately as bedrock8x posted - its not very efficient energy storage system - even when the energy used to do the compression is free (e.g. solar powered gas compressor) This is because the energy density even at very high psi is low compared to other forms of energy-propulsion systems and the mass/weight of the pressurized tank tends to become a significant burden as the psi gets higher.
Hydraulic or pneumatic for this kind of services are very inneficient. What bothers me is that many car makers keep feeding public with this kind of tech marketing crap.
