The energy that is generated and stored in the earth is called geothermal energy. It is mostly used for electricity production and is a cost-effective and environmentally friendly energy source.

1. The geothermal energy is sourced not only from the original formation of the planet but also from the radioactive decay of materials.

2. With increasing depth, the internal temperature of the earth keeps increasing. The difference in temperature between the core and the surface or the geothermal gradient drives a continuous conduction of thermal energy.

3. In areas of shallow depth, this thermal energy is often absorbed by the surrounding groundwater and rocks and often rises as steam. This steam power is then used for the generation of electricity.

4. Thus areas near plate tectonic boundaries which often have hot springs or weaker surface cover are often tapped for sourcing geothermal energy. But owing to its limited area of occurrence, it has not been fully exploited for the benefits of mankind.