U.S. Geothermal Power at Present

Part 5 of Geothermal Energy Under Our Feet. Today’s U.S. geothermal industry is a $2-billion per-year enterprise involving over 2800 MW of electricity generation capacity, about 620 MW of thermal energy capacity in direct-use applications such as indoor heating, greenhouses, food drying, and aquaculture, and over 7,300 MW of thermal energy capacity from geothermal heat […]

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Geothermal Resource Descriptions

Part 4 of Geothermal Energy Under Our Feet. Hydrothermal A hydrothermal system is defined as a subterranean geothermal reservoir that transfers heat energy upward by vertical circulation of fluids driven by differences in fluid density that correspond to differences in temperature (see Figure 2). Hydrothermal systems can be classified into two types—vapor-dominated and hot water— […]

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Geothermal Resource Definitions

Part 3 of Geothermal Energy Under Our Feet. The total resource base in the United States, both renewable and non-renewable, is very large, with an energy content of over 657,000 billion barrels of oil equivalent (BBOE), or nearly 50,000 times the annual current rate of national energy consumption. Figure 1 shows graphically what the total […]

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United States Geothermal Resources

Part 2 of Geothermal Energy Under Our Feet. The United States possesses vast underground stores of heat whose full potential has yet to be realized. The Earth’s interior reaches temperatures greater than 4,000°C (>7,200°F), and this geothermal energy flows continuously to the surface. The energy content of domestic geothermal resources to a depth of 3 […]

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Under Our Feet: Geothermal Energy

Part 1 of Geothermal Energy Under Our Feet. The Earth houses a vast energy supply in the form of geothermal resources. Domestic resources are equivalent to a 30,000-year energy supply at our current rate for the United States! In fact, geothermal energy is used in all 50 U.S. states today. But geothermal energy has not […]

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