Uniting the Spectrum of Geothermal Resources

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High-temperature Geothermal

A geothermal resource requires three things to generate electricity:

Fluid- sufficient fluid must exist in fractures and pore space within the rocks.

Heat- the rocks must be hot. Heat within the Earth's crust is generated from radioactive decay of minerals and continual heat loss from when the Earth was formed 4.6 billion years ago. Though the rocks need to be hot, the rocks are cool and brittle, relative to the more recognizable magma or lava.

Permeability- fluids must come into contact with the heated rock via fractures and pore spaces. Through these voids the fluids can circulate through the rocks, heat up, and come to the surface for electricity production.

 Medium-temperature Geothermal

Geothermal reservoirs of low-to moderate-temperature water — 68°F to 302°F (20°C to 150°C) — provide direct heat for residential, industrial, and commercial uses. This resource is used globally to heat homes and offices, commercial greenhouses, fish farms, food processing facilities, gold mining operations, and a variety of other applications. In addition, spent fluids from geothermal electric plants can be subsequently used for direct use applications in so-called "cascaded" operation.

 Low-temperature Geothermal

The geothermal heat pump, also known as the ground source heat pump, is a highly efficient renewable energy technology that is gaining wide acceptance for both residential and commercial buildings. Geothermal heat pumps are used for space heating and cooling, as well as water heating. The benefit of ground source heat pumps is they concentrate naturally existing heat, rather than by producing heat through the combustion of fossil fuels.