Geothermal relies on hot water found in reservoirs deep in the earth's crust along fault lines (mostly in the West) to produce steam that turns turbines and produces energy. After the water is used, it's returned into the earth and reused. The Department of Energy says this method emits little or no greenhouse gases. Pyper reports that geothermal is "one of the most underused sources of homegrown clean energy," saying the U.S. uses only about 2,800 megawatts to power 2.8 million homes.
However, with Google's help, the SMU researchers have mapped temperatures at greater depths than before and have found new areas of potential in the East. Research is now shifting toward enhanced systems that inject water into the ground to heat it. Sites that would support this method are larger than traditional geothermal sites and can support larger power plants, Piper reports. Existing oil and gas wells are being used to explore this method because research about the fluid properties of these wells has already been done and basins were oil and gas are extracted can have fluid reserves at many depths, increasing success of possible geothermal wells. (Read more)