geothermal energy: Quick Facts

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Nesjavellir Geothermal Power Plant

Map of the United States color-coded to show the distribution and favorability of deep enhanced geothermal systems (EGS) resources. Red and orange areas in the western states indicate the most favorable regions for geothermal energy, while yellow and light green areas in the central and eastern U.S. show less favorable or unassessed regions. Some areas are marked with gray for no data.

People relaxing in tiered hot spring pools beside a stone building, with water cascading over rocks at Bagno Vignoni, Italy.

Diagram showing how a residential geothermal heat pump works, with winter heating on the left transferring heat from underground pipes into the house, and summer cooling on the right transferring heat from the house into the ground.

Geothermal power station

Diagram of a dry steam geothermal power plant showing steam rising from an underground production well to spin a turbine connected to an electrical generator, with cooled water injected back underground and electricity sent to power lines.

This diagram shows various uses of geothermal energy at different water temperatures, ranging from 40 degreesF (4 degreesC) for heat pumps and soil warming to 700 degreesF (371 degreesC) for flash and dry steam power plants and hydrogen production, with applications like bathing, food processing, and power generation indicated along the temperature scale.

What new opportunities and risks come with harnessing geothermal energy?

Explore Ethiopia's untapped geothermal and hydropower resources

Behold near-boiling water spurting from geysers and hot springs in Wyoming's Yellowstone National Park

Tour Yellowstone National Park's geysers and hot springs and observe its wildlife

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Earth Geothermal power geothermal power geothermal heat pump thermal energy energy combustion wind power solar energy biofuel solar power steam power hydroelectric power biogas electric power tidal power

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