Informationen über Geothermie
|
|
Geothermal energy is the term given to heat stored beneath the upper part of the earth’s crust. This heat is permanently available regardless of weather conditions and the time of day. It is an attractive and economical source of energy since it is classified as regenerative and affords emission-free generation of power. Geothermal power plants use the heat stored in the earth to drive a steam turbine generator set. Compared to coal fired power plants, each installed megawatt of geothermal power station capacities can reduce CO2 emissions by around 6,500 tonnes per year. This is why some countries offer subsidies for their construction or for the electrical power from geothermal plants. Steam turbines for geothermal plants use different technologies to increase the efficiency. Siemens focuses on the ORC technology (Organic Rankine Cycle), which enables the use of low potential heat. The technology uses an organic, high molecular mass fluid with boiling-point, occurring at a lower temperature than the water-steam phase change. The fact that the working fluid vaporizes at a much lower temperature than in traditional steam-water systems makes the technology extremely suitable for low-temperature applications and enables considerably higher efficiency rates.
|
