The word root "geo-" refers to the Earth, as in geology the study of rocks or the Earth. Thermal refers to heat. So when we put the two words together geothermal refers to heat energy we get from the Earth. Many technologies are still being developed in the use of geothermal energy and many technologies are currently in use depending on the source of the geothermal energy. Geothermal energy is a clean renewable source of energy that does not utilize fossil fuels or produce greenhouse gases. The basic operation of a geothermal energy system works in this manner: A heat pump moves the water through the coils. In the summer, the ground keeps the water cooler and is pumped into the house to cool the house. In the winter, the ground keeps the water at a relatively constant temperature that is warmer than the surrounding air. This water is pumped into the house and the heat is removed and used to heat the home.
Examples of Geothermal Energy:
1. We have currently utilized geothermal energy for use in heating homes. A large coil system full of water is placed in the shallow ground in the yard. The water circulates through this coil system and the Earth keeps it at a relatively stable temperature so it costs less energy to heat it for use in homes.
2. Some power plants can utilize hot steam from vents in the Earth to power generators and create electricity.
3. Hot water springs provide direct heat applications for heating buildings.
4. Hot springs are used in bathing and health spas and have been used this way for centuries.
5. With a lake nearby, the coils can be kept at the bottom of the lake and antifreeze is added to the water in the coils to keep the water at a constant temperature, this water can be used to heat buildings or greenhouses.