Definition of Geothermal Power

What Is Geothermal Power?

Geothermal power is a form of renewable energy that taps into the heat emanating from the earth’s core. It can be used for many energy uses:

• Directly: By bringing geothermal spring water up to the earth’s surface and using it to heat homes and buildings, district water, and so on
• For electricity: High-temperature geothermal water or steam located within a mile or two of the earth’s surface is used in geothermal power plants to generate clean electricity
• In heat pumps: These use the stable temperatures found in subsurface soils or water near the earth’s surface to control building temperatures by providing cool or warm air

Using geothermal resources for space heating, electricity, water heating, and so on is extremely cost effective, sustainable, and climate change friendly (though bringing geothermal fluids up to the earth’s surface does result in the emission of some greenhouse gases such as carbon dioxide and methane in relatively small quantities). Theoretically, the amount of possible geothermal energy is far, far more than humanity could every possibly need.

Geothermal power sources are concentrated around what is called the Ring of Fire – a geographical region primarily in the Pacific Ocean where large hydrothermal resources called geothermal reservoirs are located. You can see evidence of the earth’s geothermal energy in a variety of natural phenomenon, such as:

• Volcanoes
• Fumaroles
• Hot springs
• Geysers

The United States leads the world in current geothermal power capacity in terms of megawatts produced, however it currently provides less than 1% of the nation’s energy requirements. Iceland has the largest percentage of their energy produced through geothermal power at 30% of the country’s demands.