Geothermal energy is defined as the energy stored in the form of heat below the earth's surface. At the same time, the term “geothermal energy” involves the use of geothermal energy for electricity generation and heat supply. With around 19 gigawatt hours (GWh), geothermal energy accounted for approximately 0.02 % of the total electricity generated from renewable energy sources in Germany in 2011 (Source: Federal Ministry for the Environment, Nature Conservation, Building and Nuclear Safety 2012).
In Germany, 19 geothermal power plants are in operation using deep geothermal energy (drilling depth > 400 m) - 5 of them for electricity generation. Near-surface geothermal energy (drilling depth < 400 m) to cover the heat demand is used in Germany in about 265,000 geothermal systems (Source: GtV-Bundesverband Geothermie e.V. (German Federal Geothermal Energy Association) 2012).
Tasks of GRS
Geothermal energy is one of the more recent tasks of GRS. One focal point of GRS activities is the research on the availability and safety of geothermal systems.
For this purpose, the researchers use their knowledge and experience from the traditional fields of work, such as plant safety or radiation and environmental protection. Above all, the experience from repository safety research on physical and chemical processes and interactions in the deep underground (e. g. on saline solutions, high temperatures, and material behaviour) are of great relevance for the geothermal projects.