What is geothermal energy?
Geothermal energy involves the exploitation of different kinds of thermal energy stored within the earth. In certain places, heat from deep inside the earth can rise to the surface. This heat is called geothermal energy. When water enters fissures in this hot rock, it is heated and can emerge as hot springs, or even as steam. This creates features such as steam vents, geysers and hot mud springs. Alternatively, hot water can be trapped below the earth’s surface as a geothermal reservoir. This heat can reach temperatures of 400°C and can be accessed by drilling to depths of over two miles. Ground-source heat is a different kind of geothermal energy. It is extracted from the low-temperature heat (10–20°C) that is found at relatively shallow depths within the earth’s crust. This heat source stays at a relatively constant temperature and can be taken from the ground itself or from groundwater. Heat pumps can raise the temperature of this heat to a more useful 40–50°C which is ideal for low
