What do thermal power station do for fuel?

(Geo)thermal power stations work by drilling a hole kilometers into the surface where the temperature is around 300 Cel. They then send water down the hole, and because of the almost instantaneous boiling, steam rises out at an enormous pressure which is used to drive the steam turbines which in return, generate the KW's of electricity. Efficient stations would then condense that water and use it again. This form of energy is really only useful in places where the heat underground is only not too deep since it costs a lot of money to drill deep holes underground. - Matt. Australia