An enhanced geothermal system (EGS) is a geothermal energy system that can make electrical energy when natural underground water is not there. For a long time, geothermal energy could only be produced when there were hot rocks, underground water, and cracks in rocks all together in one area. Now, new ways of getting this power source are being created. Areas that can possibly be used for energy need to be altered by people to make the energy usable. These areas may need either underground water and/or cracks, or fracture network, in rocks. Enhanced geothermal systems allow for geothermal energy to be outside normal geothermal areas like active plate boundaries to less active areas like the western United States.