Wow for car enthusiasts some people are pretty ignorant
Alternative-fuel powered cars are typically one of:
* Electric - 100% battery powered. Would have to be charged via mains. Short ranged and not very big or powerful - and not very common.
* Hybrid. Small petrol engine (say 1500cc) augments a couple of electric motors driven by battery. Typically a 400V system. These are designed to be very efficient with energy - energy lost by braking, for example, is captured and used to help keep the batteries charged.
* Hydrogen. Still very much in 'test' phase but being trialed in places like California. Powered by Hydrogen fuel cells. Hydrogen gained by electrolisis (sp) which seperates the Hydrogen and Oxygen components of Water. The catch with Hydrogen is the need to store it under pressure, and transport is awkward. Still pretty new.
Fact is, we _are_ going to run out of oil, and we _will_ get fscked over by it. We can use alternate fuels for some things - but not very easily, for example, in aviation. And don't forget the petroleum products required for the manufacture of plastics, etc. Scary when you start thinking about it really.
I say bring on alternative-fuels... !
[Disclaimer: this is all off the top of my head and open to correction.. heh]