How does geothermal power generate electricity?

Geothermal power generates electrical energy using thermal energy extracted from the Earth's crust, originating from planetary formation and radioactive decay. Technologies currently in use include dry steam, flash steam, and binary cycle power stations. Because heat extraction is small relative to the Earth's heat content and plants produce power consistently regardless of weather, it is considered a reliable renewable and sustainable energy source.

What we know

• Technologies used in operational geothermal power stations include dry steam power stations, flash steam power stations, and binary cycle power stations. [2]
• Geothermal energy combines heat from the planet's formation and from radioactive decay within the Earth's crust. [5]
• Greenhouse gas emissions from geothermal electric stations average 45 grams of carbon dioxide per kilowatt-hour, representing less than 5% of conventional coal-fired plants. [2]
• Geothermal power plants produce power at a constant rate independently of weather conditions. [5]

Still open

• Sources vary in their estimates of total global potential, with the Geothermal Energy Association estimating that only 6.9% of potential has been tapped while the IPCC reports a potential range of 35 GW to 2 TW.

Where to go next

• how it workedWhat are the three main types of geothermal power plants?
• a case in pointWhich country has the largest geothermal potential?
• compared withHow do renewable energy sources compare in global capacity?
• whereWhat is the largest geothermal power station in the world?
• whenHow was geothermal energy used historically before electricity?
• an unexpected connectionHow does radioactive decay help light homes?Electricity generated in geothermal plants relies partly on heat produced by radioactive decay occurring inside the Earth's crust.

Sources

• [1]geothermal power (Wikidata Q3215493) · CC0 1.0
• [2]Geothermal power · CC BY-SA 4.0
• [3]List of geothermal power stations · CC BY-SA 4.0
• [4]List of largest power stations · CC BY-SA 4.0
• [5]Geothermal energy · CC BY-SA 4.0