Geysers are periodic eruptions of steam in the air.
Geothermal water is groundwater that is heated by the energy of the earth. The term geothermal comes from two Greek words: geo, which means earth, and therme, which means heat. By taking advantage of the physical properties of steam and heat, geothermal water can be used to generate electricity. If the water is hot enough, it can be pumped directly to radiators and used as space heating. Some areas even bottle it and sell it as drinking water.
Hot springs occur when geothermal water reservoirs are open to the Earth’s surface.
Geothermal water reservoirs are found in places where the earth’s heat is close enough to the surface that water or steam can reach the top. There are two types of geothermal water reservoirs: low temperature reservoirs and high temperature reservoirs. Low temperature reservoirs retain water below 302°F (150°C). High temperature reservoirs hold water greater than 302°F (150°C). The deeper the reservoir is located in the earth, the warmer the water it contains.
Some areas distribute geothermal water as drinking water.
Different types of power plants have been created to convert geothermal water into electricity. Dry steam plants use the steam that comes out of the ground to turn the plant’s turbine blades. Flash steam plants use high pressure piping to bring hot water to the surface. Once on the surface, the water is then converted to steam and used to generate electricity. A binary cycle power plant uses lower temperature water to vaporize a separate fluid which is then used to produce electricity.
Some areas may bottle geothermal water and sell it to consumers.
Geothermal water reaches the surface in several ways. Hot springs are produced when the reservoir is connected to the surface by faults. Geysers are periodic eruptions of steam that can shoot up to 200 feet (60.96 m) into the air. A fumarole is an opening in the earth that emits a mixture of steam and gases. These geothermal features are usually formed around volcanic activity.
Bogs are a type of hot spring or fumarole. Bogs are puddles of bubbling mud instead of water. If the reservoir doesn’t have much water, the little water that makes it to the surface is mixed with soil filled with volcanic ash, clay and other components. This produces mud that is usually white or gray. When the mud is multicolored, it is called a paint pot.