Geothermal energy is the energy that is obtained from the core of the earth. The earth is formed of different layers. The innermost layer is the solid iron core. This is surrounded by the molten core known as magma which is nothing but hot molten rock. The core in turn is surrounded by mantle which is made up of magma and rock. The outermost layer of the earth is called the crust.
Heat is being continuously generated inside the earth’s core and flows from the core to the mantle. This energy source is the geothermal energy. The geothermal energy comes to the surface in the following three ways:
• The flow of magma through volcanoes in the form of lava.
• The flow of underground water or steam in a natural manner like in hot springs.
• The flow of underground water or steam through human efforts like geothermal plants.
The question that arises here is how does water get inside the earth? Water trickles down rock fissures when it rains. This water gets collected in an underground aquifer and gets heated by the earth’s heat. This is how water rises and flows either in the form of water or steam to the earth’s surface and hence provides us with what is known as geothermal energy.
Geothermal energy thus obtained can be used either to generate electricity or can be used for heating water, keeping buildings warm or cool and the hot water can also be used directly for cooking, bathing or for its medicinal values.