thermo-, therm-, thermi-, -thermia, -therm, -thermal, -thermic, -thermias, -thermies, -thermous, -thermy +

1. Denoting a chemical reaction during which heat is emitted.
2. Relating to the external warmth of the body.
3. A compound that liberates heat during its formation and which absorbs heat or energy during its decomposition.
4. Characterized by, or attended by, the development of heat; such as, combustion.

Relating to or describing any process in which a system releases heat to its surrounding environment.

An underground isotherm, or a line drawn on a weather map that connects places with the same temperature.

1. Relating to, or caused by, the internal heat of the earth.
2. Describing an energy system that makes use of the internal heat produced by the earth.

The use of geothermal heat in agriculture; that is, the use of low-temperature geothermal water to warm irrigation water or to sterilize soil.

The use of geothermal heat in fish farming; such as, the use of geothermally heated water to provide a controlled environment for the husbandry of marine organisms.

The process of drilling a well to explore for or to extract geothermal energy, or to re-inject thermal waste water in the ground after power generation.

You may see more information about geothermal drilling here.

1. Energy in the form of natural heat flowing outward from within the earth and contained in rocks, water, brines, or steam.
2. Heat which is produced mainly by the decay of naturally occurring radioactive isotopes of thorium, potassium, and uranium in the earth's core.
3. An energy produced by tapping the earth's internal heat. At present, the only available technologies to do this are those that extract heat from hydrothermal convection systems, where water or steam transfer the heat from the deeper part of the earth to the areas where the energy can be tapped.

The amount of pollutants found in geothermal vary from area to area but may contain arsenic, boron, selenium, lead, cadmium, and fluorides. They also may contain hydrogen sulphide, mercury, ammonia, radon, carbon dioxide, and methane.

Getting the Earth's Heat

Geothermal power plants, which tap hot subterranean water or steam, are high on the lists of at least thirty states in the U.S. which are requiring utility companies to generate some portion of their electricity from such renewable sources.

Most utilities have not pursued geothermal energy primarily because up-front costs, including exploratory drilling, can be expensive since geothermal taps deep reservoirs, not groundwater, which collects much closer to the surface.

An extensive study recently released by the Massachusetts Institute of Technology has shown that the heat available under ground is surprisingly plentiful nationwide.

The rate of temperature change in soil and rock from the surface to the interior of the earth; on the average, estimated to be an increase of about +10°C per kilometer.

1. The extraction of valuable minerals from geothermal fluids; such as, market-grade silica from a geothermal brine.
2. The process of purposely transporting geothermal energy from beneath the earth for human use; that is, the building of a well and pipeline system to bring heated water to a power plant.

A power plant utilizing geothermal energy; such as, a binary cycle plant or dry steam plant.

A subsurface system consisting of a large volume of hot water and steam trapped in a porous and fractured hot rock underneath a layer of impermeable rock.

Some reservoirs can be commercially developed as an energy source.

A localized geological environment in which circulating steam, or hot water, carries some of the earth's natural internal heat flow close enough to the surface to be utilized for productive human use.

Any technological system that makes use of this heat as an energy source; such as, to power an electrical power plant or to heat or cool a building.

Pertaining to the internal heat of the earth; or heat generated in the interior of the earth.

1. The direct or indirect measurement or approximation of the temperatures at which geologic processes take place or have taken place.
2. The study of the earth's heat and temperatures, and their effects on geologic processes.
3. The study of the earth's heat and subsurface temperatures.
4. In geology, a mineral or aggregate of minerals whose presence defines the temperature range of limits within which the minerals were formed; also known as a geologic thermometer.