The term “geothermal” is derived from the Greek words for Earth (geo) and heat (therme). In essence geothermal energy is power harnessed from the Earth itself. Heat from the Earth’s core, which averages about 6,650 degrees Fahrenheit, emanates out toward the planet’s surface. Heated springs and geysers up to three miles underground can be accessed by special wells that bring the hot water (or steam from it) up to the surface where it can be used directly for heat or indirectly to generate electricity by powering rotating turbines. Since the water under the Earth’s surface is constantly replenished, and the Earth’s core will continue to generate heat indefinitely, geothermal power is ultimately clean and renewable.