Air: energy source of the future?

Two exciting research projects have highlighted the potential of air to play a key role in a renewable energy future.

Last week saw the press reporting on a new air-powered car that instead of being powered by an internal combustion engine, uses compressed air technology to drive pistons in the engine. Of course an external energy source is still needed to compress the air, but with the possibilty of this being achieved using renewable sources, and with CO2 emissions a fraction of petrol engines, it is still an exciting breakthrough.

A similar breakthrough has been unveiled today by the Engineering and Physical Sciences Research Council (EPSRC): a new air-fuelled battery that may be able to give out ten times more energy than conventional designs. Oxygen drawn from the air reacts with material inside to release the electrical charge in the lithium-air battery. Not having to carry traditional chemicals around inside the battery offers the potential for more energy for the same size of battery. Reducing the size and weight of batteries has been a long-running battle for developers of electric cars.

The STAIR (St Andrews Air) cell should be cheaper than current rechargeable batteries too. The new component is made of porous carbon, which is far less expensive than the lithium cobalt oxide it replaces.

Principal investigator on the project, Professor Peter Bruce of the Chemistry Department at the University of St Andrews, estimates that it will be at least five years before the STAIR cell is commercially available.

Read more:
http://www.epsrc.ac.uk/PressReleases/oxlithbattery
http://www.guardian.co.uk/environment/2009/may/14/air-powered-car-hybrid-france