Summary
Highlights
Geothermal energy is produced from the Earth's internal heat, generated by radioactive decay of minerals and residual heat from the Earth's formation. Wells are drilled 3 to 10 kilometers deep to extract this heat, typically using water and steam.
Hot water extracted from the Earth can directly heat homes and buildings, either by circulating it through structures or using heat exchangers. Geothermal heat can also generate electricity in power plants by producing steam to turn turbines.
Geothermal development is prominent in volcanically and tectonically active regions. A key advantage of geothermal energy is its reliability and consistent power generation, making it suitable for providing baseload electricity, despite currently being a small part of the global energy mix.
Concerns include the accidental release of CO2 and hydrogen sulfide emissions stored in groundwater used to transfer heat. Irresponsible heat extraction can also lower ground temperature. Geothermal energy has high upfront costs due to expensive seismic sensing, drilling, testing, and preliminary investigations required to ensure production goals are met.