New Push in Geothermal?

Hi Craig,

I think this news is exciting as finally geothermal power and heat can potentially be produced anywhere – with closed loop systems which do not need fracking or large volumes of water – and I would say no real risk of triggering earthquakes as there is no fracking to trigger movement.  True, for the moment, cost will probably be a little high, but that can change, and probably will if adopted at scale.

Gary: I’m skeptical.  To be honest, I’m always skeptical when oil companies say they want to pursue something they know essentially nothing about that, if successful, will put themselves out of business.

Beyond that, there is no getting around the fact that geothermal requires drilling through the hardest rock in the Earth’s crust (where oil exploration normally drills through far softer rock).  And needless to say, going deeper only adds cost.

Also, the way I understand it, geothermal doesn’t involve fracking.  It’s based on finding hot brine at the bottom of one hole that can be pumped up to the surface and run through a heat exchanger, then reintroduced into another hole nearby.  The rock at the bottom needs to be porous, so the brine can move through it back to the bottom of the first hole, so as to complete the circuit endlessly. At least that’s what I took from my interview with the guy from Ormat, as the chapter on geothermal in Renewable Energy–Facts and Fantasies.

Thanks for thinking of me, as always.