Drill down just a few miles into the earth’s crust, and the temperature will rise substantially. This heat comes from three sources: emissions from radioactive minerals, the compressive force of gravity, and to a lesser extent, solar energy absorbed at the earth’s surface. Although such energy is not truly renewable (radioactive elements do eventually decay to energy-flat states), within any reasonable estimate of mankind’s tenancy on this planet, geothermal power is essentially limitless.
There are several techniques for transducing this energy from underground heat to in-the-grid electricity. One of these, a technology called Enhanced Geothermal Systems (EGS), is currently being tested by Sausalito-based AltaRock Energy only 12 beeline miles from my home in Northern California. Continue reading “Enhanced Geothermal Energy and Man-Made Earthquakes”