Geothermal energy is thermal energy generated and stored in the Earth. Thermal energy is the energy that determines the temperature of matter.
Earth’s internal heat is thermal energy produced from radioactive decay and constant heat reduction from the formation of Earth. Temperatures at the center–mantel boundary may reach over 4000 °C (7,200 °F). The high temperature and pressure in the interior of Earth induce some rock to melt and solid layer to behave plastically, causing pieces of mantel convecting upward since it is lighter compared to the surrounding stone. Rock and water is warmed in the crust, occasionally up to 370 °C (700 °F).
From hot springs, geothermal energy is used for bathing since Paleolithic times and for space heating since ancient Roman times, but it really is known for electricity generation. An added 28 gigawatts of direct geothermal heating ability is installed for desalination, space heating, spas, industrial processes, district heating and agricultural applications in 2010. Geothermal power is cost effective, dependable, sustainable, and environmentally friendly, but has historically been restricted to places near tectonic plate boundaries.
Recent technological improvements have dramatically expanded the range and size of workable resources, notably for programs for example home heating, opening a potential for widespread exploitation.
These emissions are much lower per energy unit than those of fossil fuels, although greenhouse gases trapped deep within our planet are released by geothermal wells. Consequently, geothermal power has the potential to help mitigate global warming if widely deployed in place of fossil fuels. The Earth’s geothermal resources are theoretically more than sufficient to supply the energy needs of humanity, but just a tiny fraction may be utilized. Exploration and drilling for resources that are deep is hardly cheap.
Outlooks for the future of geothermal power depend on assumptions about interest rates, and technology, energy prices, subsidies. But as a result of authorities assisted industry and research expertise, the expense of producing geothermal power has decreased by 25% over the previous two decades. In 2001, geothermal energy costs between two and ten US cents per kWh.