Geothermal power plants harness heat from the Earth's core to generate electricity. There are three main types - dry steam, flash steam, and binary cycle plants. Dry steam plants extract steam directly from reservoirs over 175C, while flash plants produce steam from hot water above 150C that flashes upon reaching the surface. Binary plants use lower-temperature water above 100C to boil a secondary fluid and drive turbines. Geothermal energy has significant advantages as it produces little emissions or pollution and requires less land than other energy sources. Further development could access immense heat resources and allow a large-scale, environmentally friendly renewable energy option.