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Geothermal power plant
Cyril Ruoso/Minden Pictures/National Geographic Creative

Iceland’s Svartsengi (“Black Meadow”) geothermal power plant, located on the Reykjanes Peninsula in Iceland, was the first geothermal plant designed to both create electricity and provide hot water for district heating. With six different plants, it generates 75 megawatts of electricity, enough to supply 25,000 homes. Its “waste” hot water is piped to the Blue Lagoon Geothermal Spa, visited by 400,000 guests annually.

Geothermal Power

Reduce SourcesElectricityShift Production
6.19–9.85
Gigatons
CO2 Equivalent
Reduced / Sequestered
(2020–2050)
$80.6–86.45
Billion $US
Net First Cost
(To Implement Solution)
$0.81–1.22
Trillion $US
Lifetime Net
Operational Savings
Underground reservoirs of steamy hot water are the fuel for geothermal power. It can be piped to the surface to drive turbines that produce electricity without pollution.

Solution Summary*

The heat energy contained below the earth’s surface is about 100 billion times more than current world energy consumption. Geothermal power—literally “earth heat”—taps into underground reservoirs of steamy hot water, which can be piped to the surface to drive turbines that produce electricity. That feat was first accomplished in Larderello, Italy, on July 15, 1904.

Prime geothermal conditions are found on less than 10 percent of the planet, but new technologies dramatically expand production potential. One new approach targets deep underground cavities and adds water to create hydrothermal pools where they do not currently exist. Care must be taken, as the means to access these cavities can create micro-earthquakes.

With subterranean resources flowing 24-7, without interlude, geothermal production can take place at all hours and under almost any weather conditions. Geothermal is reliable, abundant, and efficient. While drilling is expensive, the heat source itself is free. According to the Geothermal Energy Association, 39 countries could supply 100 percent of their electricity needs from geothermal energy, yet only 6 to 7 percent of the world’s potential geothermal power has been tapped.

* excerpted from the book, Drawdown
Impact:

Our calculations assume geothermal power grows from 0.34 percent of global electricity generation to 2.6-2.8 percent by 2050. That growth could reduce emissions by 6.2-9.8 gigatons of greenhouse gases and save $0.8-1.2 trillion over the lifetime of the infrastructure. By providing baseload electricity, geothermal also supports expansion of variable renewables.