The word geothermal comes from the Greek words geo (earth) and therme (heat). So, geothermal energy is heat from within the Earth. We can recover this heat as steam or hot water and use it to heat buildings or generate electricity.It is a natural part of the energy flow within the Earth’s depths.
Generally speaking, the further down one drills, the hotter the temperatures. Most of the commercial-grade production geothermal energy is harvested along localized “geothermal systems”, where the heat flow is near enough to the surface that hot water or steam is able to rise either to the surface, or to depths that we can reach by drilling. Many of these regions occur within the “ring of fire“, a ring of geothermal sites