Geothermal heat extraction from tight sedimentary reservoirs (GeneSys)
The GeneSys project aims at the development and implementation of new concepts for the direct use geothermal heat.
The location Hannover is an exemplary one: Target rocks are the formations of the Mid Triassic. In a depth of 3,300 m to 3,600m, these thick formations have a temperature of 120°C to 140°C. These rocks are a common type for northern Germany. In most cases, their permeability is not sufficient for the conventional production of hot water. Therefore, an artificial fracture will be created in the bedrock which acts as a heat exchanger. The heat energy of the produced hot water will be extracted by a surface heat exchanger and fed into a heating circuit. The cooled down water is then going to be injected into a shallower rock layer via the same borehole.
GeneSys Horstberg
Many things happened during the past years: Since 2003 the GEOZENTRUM is operating a 4,100 m deep geothermal research well in the ”Südheide” in order to prove new, innovative concepts for the extraction of geothermal heat. During tests in this well, the new concepts have been proven to be applicable also at the conditions at the location in Hannover. Finally, this was the starting shot for the project GeneSys Hannover.
R&D at the well site Horstberg is funded by the Federal Ministry for the Environment, Nature Conservation and Nuclear Safety.
Research in Hannover
In November 2009, a 3,901 m deep (MD) geothermal well was drilled at the premises of the GEOZENTURM in the city of Hannover by the Federal Institute for Geosciences and Natural Resources (BGR). Large scale artificial fractures are going to be created at a depth of approximately 3,800 m which will act as a heat exchanger. This will be followed by a long term test-operation in order to determine the performance of the geothermal system. Coupling the geothermal sub-surface system with the GEOZENTRUMs heating system can provide heat energy for several decades. The Leibniz Institute for Applied Geosciences will take this unique chance of a geothermal well right on the premises of the GEOZENTURM to investigate further geologic strata for geothermal use and to develop new methods for geothermal reservoir evaluation within a research project funded by the Federal Ministry for the Environment, Natural Conservation and Nuclear Safety.