Geo-thermal energy
Geo-energy involves the exploitation of different grades of thermal energy stored within the Earth, which are exploited as ground source heat and as geo-thermal energy, Geo-thermal energy is derived from the very high temperatures at the Earth's core, and ground source heat exploits solar energy that has been stored at relatively shallow depths within the Earth.
In geologically suitable areas, heat from deep within the Earth's interior can rise Up to the surface. Such heat is referred: to as geothermal energy. Whenever water enters fissures in this hot rock, it can become heated and can emerge on the surface as hot springs, or even as steam, creating features such as steam vents, geysers and hot mud springs.
Alternatively, heated water can be trapped below the Earth's surface as A geothermal reservoir. This heat can reach temperatures of 400 degrees Celsius and can be accessed by drilling to depths of over two miles underground.
Ground source heat is extracted from the low temperature heat (around 1O-20 degrees Celsius) that is found at relatively shallow depths within the Earth's crust. This source of heat remains at a relatively constant temperature all year and can betaken from the ground or from water within the ground (groundwater). Heat pumps can increase the temperature of this heat to provider a more useful output temperature of around 40-5O degrees Celsius which is ideal for Low temperature heating systems like under floor systems and radiant panels.
Only one geothermal power plant is in operation in the UK, at Southampton. Ground source heat pumps were first popular in the early 1980's, when electricity was cheaper than gas, and are becoming increasingly popular due to their energy efficient status and due to the fact that gas prices are once more beginning to rise. There are an increasing number of heat pumps installed throughout the U.K in homes, commercial buildings, swimming pools etc. Geothermal power plants require relatively little space and no damming of rivers or harvesting of forests. Exploitation of geothermal energy does not create any mineshafts, tunnels, open pits, waste heaps or oil spills. Geothermal plants can sit amongst potentially sensitive developments such as farmland and forests and can share land with cattle and local wildlife.