Geothermal energy is concentrated in the area along the edge of the tectonic plate, which is also a volcanic and earthquake-prone area. If the rate of heat extraction does not exceed the rate of replenishment, the geothermal energy is regenerable. Geothermal energy is widely used in many parts of the world. It is estimated that the annual heat transfer from the interior of the Earth to the ground is equivalent to 100 PW·h. However, the distribution of geothermal energy is relatively scattered and difficult to develop.

According to a survey conducted by the United States Geothermal Resources Commission (GRC) in 1990, 18 countries in the world have geothermal power generation with a total installed capacity of 5,827.55 megawatts. The countries with installed capacity of more than 100 megawatts include the United States, the Philippines, Mexico, Italy, New Zealand, and Japan. And Indonesia. China's geothermal resources are also very rich, but the degree of development and utilization is very low. Mainly distributed in Yunnan, Tibet, Hebei and other provinces.

The world's geothermal resources are mainly distributed in the following five tropical regions:

1 ring in the Pacific Ocean. The collision boundary between the world's largest Pacific plate and the Americas, Eurasian, and Indian plates, from Alaska, California to Mexico, Chile, New Zealand, Indonesia, and the Philippines to China's coastal areas and Japan. Many geothermal fields in the world are located in the tropical regions of the world, such as the Gaither geothermal field in the United States, Prieto in Mexico, Wailakai in New Zealand, the manger in Taiwan, and the geothermal fields in Matsukawa and Dayue in Japan.

2 Mediterranean, Himalayan tropical. The collision boundary between the Eurasian plate and the African and Indian plates, from Italy to China. For example, the Ladero geothermal field in Italy and the Yangbajing in Tibet, China and the Tengchong geothermal field in Yunnan belong to this area.

3 Atlantic ridges in the tropics. The cracking of the Atlantic plate includes some geothermal fields in Iceland and the Azores.

4 Red Sea, Gulf of Aden, and the rift valley of East Africa. It includes geothermal fields in Kenya, Uganda, Zaire, Ethiopia, Djibouti and other countries.

5 other geothermal areas. In addition to the geothermal area formed by the boundary of the plate, there are high heat flow areas under certain geological conditions in the part near the boundary of the plate, which can contain some medium-low temperature geothermal fields, such as some geothermal fields in Central Asia and Eastern Europe, and China's Jiaodong. Geothermal fields in the Liaodong Peninsula and the North China Plain.

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