Geothermal Energy

The word geothermal comes from the Greek words geo (earth) and therme (heat). So, geothermal energy is heat from within the earth. We can use the steam and hot water produced inside the earth to heat buildings or generate electricity. Geothermal energy is a renewable energy source because the water is replenished by rainfall and the heat is continuously produced inside the earth.
ENERGY INSIDE THE EARTH
Geothermal energy is generated in the earth's core, about 4,000 miles below the surface. Temperatures hotter than the sun's surface are continuously produced inside the earth by the slow decay of radioactive particles, a process that happens in all rocks. The earth has a number of different layers:
The core itself has two layers: a solid iron core and an outer core made of very hot melted rock, called magma.
The mantle which surrounds the core and is about 1,800 miles thick. It is made up of magma and rock.
read more