Q9Power Generation Sources
Question
Q.9. What is geothermal energy?
Answer
Geothermal energy is the heat energy stored within the Earth's crust (from radioactive decay and residual heat from formation), extracted as steam or hot water from underground reservoirs to generate electricity or provide direct heating.
Geothermal energy originates from the natural heat contained within the Earth, produced by the radioactive decay of minerals in the crust and mantle and residual heat from the planet's formation. In regions with high geothermal gradients, underground reservoirs of hot water/steam (hydrothermal resources) are tapped through wells; the extracted steam directly drives a steam turbine-generator, or the hot water is flashed to steam or used in a binary-cycle heat exchanger to vaporize a secondary low-boiling-point fluid that drives the turbine.