Geothermal energy is the energy stored in the form of heat below the earth’s surface. Its potential is limitless in human terms and its energy is comparable to the sun. Geothermal heat and water have been used for thousands of years. The Romans, Chinese and Native Americans used hot mineral springs for bathing, cooking and for therapeutic purposes.
Today geothermal water is used in many applications such as district heating, systems which provide steam or hot water to multiple units, as well as for heating and cooling of individual buildings, including offices, shops and residential houses, by using geothermal heat pumps. Moreover, it has industrial potential for raising plants in greenhouses, drying crops, heating water at fish farms and other industrial processes.
For close to 100 years geothermal energy has also been used for electricity generation. Today, so called Enhanced Geothermal Systems (EGS, also known as Hot Dry Rock), enable the exploitation of the Earth’s heat for producing electricity without having natural water resources. To extract energy from hot impermeable rock, water is injected from the surface into boreholes in order to widen them and create some fractures in the hot rock. Flowing through these holes, the water heats up and, when it returns to the surface, it is used for generating electricity.
Clean, renewable, constant and available worldwide, geothermal energy is already being used in a large number of thermal and electric power plants.
Read more about:
- European Geothermal Energy Association (EGEC)
- IEA – Geothermal Energy
- European Renewable Energy Council (EREC)