How Geothermal Works (Sandy Turner)
Sandy Turner is fired up about geothermal power. Find out how this hot resource helps satisfy California's energy appetite.
Transcript: Geothermal Works
In order to have geothermal you have to have certain things, you have to have the magma which is your heat source, then you have a layer of permeable rock which has the cracks and the fissures so the water can get in there, so the heat flashes it so it becomes steam and its trapped in there by a reservoir cap rock so the steam can't get out of there. So then what we do to tap into that energy is we drill through the cap rock down into the fissures and it releases the steam. The pressure brings it up - the steam comes out of the ground at about 350degrees fahrenheit and about a 100 psi into the plant. Most places in the world where you don't have that intense heat that close to the surface, it's not economically feasible to drill down far enough where you can get to the hot water. We're just fortunate that it's so close to the surface. the other thing that we're very fortunate about at the geysers is that our steam is a dry steam. It comes out without any water or with very little water in it. Other places in the world generally have water with their steam so that creates more of a problem for them when the steam comes up they have to flash that they have to use a heating process to flash that water into steam as well. We don't have to deal with that, ours comes straight out the way we have to use it.