Geothermal power is obtained from the Earth. In Greek geo means earth and therme means heat. Geothermal power plants harness the heat from the earth to produce electricity.
Since geothermal energy isn't used often there isn't very much equipment, workers, and infrastructure. Also geothermal energy requires installation of power plants, which are very costly.
Geothermal energy is an environmentally friendly, renewable, and sustainable source of electricity. It does not release greenhouse gases making it not effect global warming in any shape, way, or form.