Yellow Canary

Earth Energy


Earth energy systems take the solar heat that is absorbed in the earth's surface, and transfers it into a home or office where it is converted into warm air or warm water for distribution in air ducts or radiant water. It can also provide 100% of a building's demand for hot water. During summer, the system is reversed to transfer interior building heat into the back yard via the same buried loop, where it is rejected into the ground to provide air conditioning for building occupants. It's more efficient to use earth energy than it is to use a combustion furnace. That's because it requires less energy to move heat from one place to another than it does to convert one kind of energy into another, which is what a furnace does.

Ground source heat pumps (GSHPs) are electrically powered systems that tap the stored energy of the greatest solar collector in existence: the earth. These systems use the earth's relatively constant temperature to provide heating, cooling, and hot water for homes and commercial buildings. One of the most efficient residential heating and cooling systems available today, with heating efficiencies 50 to 70% higher than other heating systems and cooling efficiencies 20 to 40% higher than available air conditioners. Can be a combination heating/cooling and hot water heating system. Change from one mode to another with an indoor thermostat. Using a desuperheater, some GSHPs can save you up to 50% on your water-heating bill by preheating tank water.

What is Geothermal?

Geothermal Energy is heat (thermal) derived from the earth (geo). It is the thermal energy contained in the rock and fluid (that fills the fractures and pores within the rock) in the earth's crust. In most areas, this heat reaches the surface in a very diffuse state. However, due to a variety of geological processes, some areas, including substantial portions of many western states, are underlain by relatively shallow geothermal resources.

These resources can be classified as low temperature (less than 90°C or 194°F), moderate temperature (90°C-150°C or 194-302°F), and high temperature (greater than 150°C or 302°F). The highest temperature resources are generally used only for electric power generation. Uses for low and moderate temperature resources can be divided into two categories: direct use and ground-source heat pumps.

Direct use involves using the heat in the water directly (without a heat pump or power plant) for such things as heating of buildings, industrial processes, greenhouses, aquaculture (growing of fish) and resorts. Direct use projects generally use resource temperatures between 38°C (100°F) to 149°C (300°F).

Ground-source heat pumps use the earth or groundwater as a heat source in winter and a heat sink in summer. Using resource temperatures of 4°C (40°F) to 38°C (100°F), the heat pump, a device which moves heat from one place to another, transfers heat from the soil to the house in winter and from the house to the soil in summer.
excerpt from Geothermal Energy, Clean Sustainable Energy for the Benefit of Humanity and the Environment, from the Energy and Geoscience Institute, University of Utah.


National Renewable Energy Laboratory—Geothermal Technologies Program: Focuses in three areas: energy systems research and testing (working to enhance conversion of geothermal energy into heat and electricity) led by NREL; drilling technologies research (for both hardware and diagnostic tools) led by Sandia National Laboratories; and geoscience and supporting technologies research (exploration and resource management).

Not In My Back Yard (NIMBY): is a term used to express the opposition of people to generating stations or nuclear reactors in their neighbourhood. This opposition to visible energy facilities exists around the world, and includes occasional resistance to wind turbines and rooftop solar collectors based on reasons ranging from health and ecology, to aesthetics and property values. NIMBY promotes the use of Earth Energy.

International Ground Source Heat Pump Association: IGSHPA, 374 Cordell South, Stillwater, OK, 74078, (405) 744-5175, Fax: (405) 744-5283, Non-profit, member driven organization established in 1987 to advance geothermal heat pump (GHP) technology on local,state, national and international levels.

EERE's Geothermal Technologies Program, U.S. Department of Energy, Office of Efficiency and Renewable Energy, 1000 Independence Ave. S.W., Washington, DC, 20585. Works in partnership with U.S. industry to establish geothermal energy as an economically competitive contributor to the U.S. energy supply. Geothermal energy production generates electricity or provides heat for direct applications including aquaculture, crop drying, and district heating, or for use in heat pumps to heat and cool buildings.

Idaho National Engineering and Environmental Laboratory—Geothermal Program, P.O. Box 1625, Idaho Falls, ID 83415. INEEL's Geothermal Program investigates and develops geothermal resource technologies for both direct use and electricity generation, particularly those resources considered marginally economical.

The Geothermal Resources Council: Serves as a focal point for continuing professional development for its members through its outreach, information transfer and education services.

Earth Energy Systems, 51 Foley Street, Santa Rosa, CA 95401, (707)523-4363, Fax (707)523-4360, Designs and installs geoexchange heating, cooling, and hot water systems for homes and commercial buildings in California. Safe, clean, and efficient heating, air conditioning, and hot water heating. Geoexchange systems work with both forced air and radiant systems.

Earth Energy Technology & Supply, Inc., 505 NE 2nd Ave., PO Box 219, Marietta, OK 73448, 800-771-9455, Fax: 580-276-9459, Supplier of equipment, piping, special fabrication, and technical services to geothermal projects across the United States.

Canadian Renewable Energy Network: Earth Energy: Technologies & Applications, Transferring Heat Using Pipes Under the Ground or in Water, Guidelines for Installing Earth Energy Systems, Transferring heat from water, Saving money with Earth Energy, Generating electricity with geothermal energy, Reducing greenhouse gases with earth energy, Using hot water from the ground to provide heat.

Earth Energy Society of Canada, c.a.r.e., 435 Brennan, Ottawa, K1Z 6J9, (613) 371-3372, (371-EESC), Fax: (613) 822-4987, info @ Represents the domestic earth energy (ground-source / geothermal heat pump) industry, with a mission to promote quality installations and to promote earth energy technology as a viable economic and environmental option in Canada's energy scenario. Responsible for developing and delivering adequate and relevant training for practitioners, and promoting applications on economic and environmental bases.

EarthEnergy™ Limited: UK's leading Geothermal Energy company, specialising in Ground Source Heat Pump systems to provide Renewable Heating and Cooling for buildings across the country. A domestic EarthEnergy™ System can be used to provide both hot water and heating for your home. Technology is reliable, sustainable and can reduce heating energy consumption by up to 75%.

Geothermal Organizations & Universities