The system consists of two bore holes which penetrates the earths crust into a region bottom of injection hole to fracture the rocks. During construction an explosive charge would be detonated at the bottom of injection hole under pressure. It would then penetrate the hot rock, pick up heat and return to the surface via the second borehole. At the surface , steam would be released from the pressurized system to drive turbine generators.
Geothermal energy is also used to directly heat individual buildings and to heat multiple buildings with district heating systems. Hot water near the earth's surface is piped into buildings for heat. ... Industrial applications of geothermal energy include food dehydration (drying), gold mining, and milk pasteurizing.
Geothermal power plants use steam to produce electricity. The steam comes from reservoirs of hot water found a few miles or more below the earth's surface. The steam rotates a turbine that activates a generator, which produces electricity.
Almost anywhere in the world, geothermal heat can be accessed and used immediately as a source of heat. This heat energy is called low-temperature geothermal energy. Low-temperature geothermal energy is obtained from pockets of heat about 150° C (302° F). Most pockets of low-temperature geothermal energy are found just a few meters below ground.
Low-temperature geothermal energy can be used for heating greenhouses, homes, fisheries, and industrial processes. Low-temperature energy is most efficient when used for heating, although it can sometimes be used to generate electricity.
Co-produced geothermal energy technology relies on other energy sources. This form of geothermal energy uses water that has been heated as a byproduct in oil and gas wells.
In order to obtain enough energy to generate electricity, geothermal power plants rely on heat that exists a few kilometers below the surface of the Earth. In some areas, the heat can naturally exist underground as pockets steam or hot water. However, most areas need to be “enhanced” with injected water to create steam.