can replace all the power generated by nuclear energy with wind and solar. wind, solar and geothermal all depend on geography. tell me what has to be in place to use geothermal. >> you are absolutely right. and there is no way we'll ever -- of the power generation coming from coal, natural gas, nuclear. but where wind, geothermal and solar play a big role is where is the power in the next decade going to come from? and it can come from these sources. they're renewable, they're clean, they reduce our independence on foreign sources. these are generally geographical from a geothermal perspective in the west. so in the western u.s., we hope where the mountain building is between the two ranges, there's significant and very wide based resources of hot water that are subsurface, they're within the depths of our drilling costs horizons, so that would be somewhere around a mile or less. and those pools where where we