[scooter2]

Abundant, yes. However, it's going to be very expensive to create such reservoirs in areas where near-surface geothermal sources are not available.

[RightWhale]

That's the problem. Whatever is done will take building of infrastructure and even if the energy is free the infrastructure is not. Same problem as solar cells and wind power.

[eraser2005]

It doesn't seem like you would need a natural geothermal source like a geyser (think Iceland or Yellowstone)...

Heck, you can get a geothermal heat pump in the middle of Ohio that is enormously efficient. While you get about 93% efficiency out of a gas furnace, you can get 300+% efficiency out of a geothermal heat pump - all that is doing is extracting heat energy from the earth. That's not that unlike what this is proposing. Just think of an open loop system rather than closed loop, and on a MUCH bigger scale...

[bpjam]

Let California live off of geothermal energy. That would reduce the national consumption by about 20% right there and reduce the price of everything else. But, being California, if there is a solution to some problem they will find a way to screw it up, over-regulate it or simply ban it because it causes some other problem (like smell, or heat, or pollution, or noise). Just watch. Its one of the only constants in the universe - the ability of the State of California to foil any solution to any problem.

Nevada is also a huge source for geo-thermal energy in the areas which are entirely owned by the Federal Government and used as a buffer between civilization and the secret air force base which doesn't exist a couple hours north-northwest of Las Vegas.