Global geothermal capacity installations by region 2015
Global geothermal energy
Geothermal energy is derived from energy that is contained within the rocks and fluids in the earth’s crust. This energy originated during the formation of the Earth and remains active due to the continuous radioactive decay of these materials. The geothermal gradient, which is based on the differences in temperature of the Earth’s core and surface, drives a conduction of thermal energy (i.e. heat). Advancements in technology have rendered an expansion of the range and size of geothermal power sources. However, only a relatively small portion of geothermal sources are economically viable for human energy use.
In 2015, Asia was one of the leaders of generating geothermal energy, totaling over 4,500 megawatts of installed capacity, followed by North America with approximately 4,300 megawatts of installed geothermal capacity. The Philippines and Indonesia are among the top countries in regards to installed geothermal capacity with 1.9 gigawatts and 1.4 gigawatts, respectively in 2014. However, during this year, the United States was still the largest geothermal energy user by far in the world, with 3.5 gigawatts of installed capacity. California had just under three megawatts of the country’s installed geothermal energy . The majority of geothermal hot water reservoirs are located in the west, as well as Hawaii and Alaska. The presence of geothermal energy also produces hot springs which have been used for bathing and space heating since ancient times.