Most geothermal developments use natural hot spring areas, but a new method may have great promise and danger-
Geothermal energy is regarded as a quasi renewable energy source because it does not use fossil fuels, uses the natural heat of the earth, and can be turned into clean electricity or for lower temperature sources for space heating by circulation of warm water. Iceland has made great strides in geothermal development.
However, hot spring areas do not occur everywhere, their useful life for geothermal energy is limited in time, and unique natural and scenic features are often destroyed in development.
As a result, developers want to drill deeper using the natural heat gradient of the Earth. The easiest way to do this is down a fault which provides a natural crack often leading to heat. Of course, faults are the cause and the result of earthquakes. Lubricating the fault with water seems a bit scary, but surprisingly a program is underway with more coming Idaho, Nevada, and California.
Deep in Bedrock, Clean Energy and Quake Fears. By James Glanz. New York Times.
My photo of an abandoned geothermal well in Raft River Valley, Idaho.