GEO marta y alex

Geothermal energy is thermal energy from the Earth. It comes from the original formation of the planet (20%) and from radioactive decay of minerals (80%).At the core of theEarth, thermal energy is created by radioactive decay and temperatures may reach over 5000 degrees Celsius.

Heat conducts from the core to surrounding cooler rock. The high temperature and pressure cause some rock to melt, creating magma convection upward since it is lighter than the solid rock.The magma heats rock and water in the crust, sometimesup to 370 degrees Celsius.

Worldwide, about 10,715 megawatts (MW) of geothermal power is online in 24 countries. An additional 28 gigawatts of direct geothermal heating capacity is installed for district heating, space heating, spas, industrial processes, desalination and agricultural applications.

Geothermal power is cost effective, reliable, sustainable, and environmentally friendly, but has historically been limited to areas near tectonic plate boundaries.

The Earth's geothermal resources are theoretically more than adequate to supply humanity's energy needs, but only a very small fraction may be profitably exploited. Drilling and exploration for deep resources is very expensive.Forecasts for the future of geothermal power depend on assumptions about technology, energy prices, subsidies, and interest rates.Polls show that customers would be willing to pay a little more for a renewable energy source like geothermal. But as a result of government assisted research and industry experience, the cost of generating geothermal power has decreased by 25% over the past two decades.In 2001, geothermal energy costed between two and ten cents per kwh.

Geothermal energy by:	Marta Otero
	Alejandro Calderon