Geothermal energy is a renewable and sustainable source of power derived from the heat stored beneath the Earth’s surface. It can be harnessed for various purposes, including electricity generation and direct heating and cooling. Geothermal energy primarily comes from two main sources:
- Volcanic and Hydrothermal Sources:
- Geothermal Reservoirs: These are areas where water seeps into the Earth’s crust and is heated by the Earth’s geothermal gradient, which causes the water to rise back to the surface as steam or hot water. These reservoirs are typically located near tectonic plate boundaries and are associated with volcanic activity.
- Hot Springs and Geysers: These are surface manifestations of geothermal reservoirs where hot water and steam naturally emerge from the Earth. Famous examples include Yellowstone National Park’s geysers like Old Faithful.
- Enhanced Geothermal Systems (EGS):
- In areas without natural geothermal reservoirs, engineers can create their own by drilling deep wells into hot rocks and injecting water into them. This process fractures the rocks and creates permeability, allowing for the circulation of water and the extraction of heat. EGS can expand the geographical range of geothermal energy production.
​Read about the types of geothermal energy applications.