Abstract: A method for extracting and utilizing geothermal energy present in the earth's interior is based on at least one essentially vertical bore hole into the ground, the bottom zone of which is provided with penetrating passages into the surronding rock. A heat-conducting substance is forced into the penetrating passages. At least one supply and one return line for a heat transmission medium is thermally linked with the heat-conducting substance and the surrounding rock. The heat transmission medium is conveyed in a circuit in which part of its heat content is extracted and industrially utilized before reintroducing the fluid into the ground.