How deep would you have to drill to heat water to a high enough degree to make it FE
can u be more specific? Earth heat is renewable energy source like wind or solar ,so in a sence it is FE(noone is charging for heat taken from earth,wind,solar).As with all renewables u have only initial costs of instalation and maintanance.In Island u have shallow drillings i guess,try to read something on their power generation.
OP, it already exists as Geothermal power, every where a hot water spring exists naturally.
Regards.
There's a company in California operating a commercial power generation plant. I saw it on TV some time ago, I think it was Discovery Channel.
They said it varies based on location, some areas are very hot near the surface and so are easier to tap. But they also said, that even in a normal (non-hot) area, they can use oil drilling techniques to drill down 5-6miles and get temperatures of 400+F so it should be possible to do anywhere.