EUROPEAN RESEARCH INFRASTRUCTURE ON SOLID EARTH

Groβ Schönebeck, DE

The Deutsches GeoForschungsZentrum (GFZ) geothermal research platform, Groß Schönebeck, is situated northeast of Berlin on the southern edge of the North German Basin....


The Deutsches GeoForschungsZentrum (GFZ) geothermal research platform, Groß Schönebeck, is situated northeast of Berlin on the southern edge of the North German Basin. In 2001, the abandoned Groß Schönebeck (E GrSk E3/90) gas exploration well was reopened by GFZ Potsdam, and deepened to 4300 m with the intention of using the well for geothermal research. A second well (Gt GrSk4/05) was drilled in 2006 in order to establish a geothermal (extraction and injection) doublet. The wells give access to low permeability water-bearing horizons at depths between 3.9 and 4.4 km at temperatures of 150°C, i.e. hot enough to operate steam turbines and generate power. They are used as an in situ laboratory for investigating deep sedimentary structures and fluids under natural conditions. Research activities take holistic approach along the whole chain of geothermal technologies, from the geothermal reservoir to the provision of power, heat and chill.

The downhole laboratory represents an important pilot project for the development of geothermal technology in Europe. In situ experiments and borehole measurements can be performed to improve the productivity of low-permeability geothermal reservoirs to create Enhanced Geothermal Systems (EGS). The research platform also includes facilities for testing plant components and materials.

GFZ is using the facility to develop methods to recover geothermal heat from sandstones and volcanic rocks in the Rotliegend formation, and to study the feasibility, sustainability, environmental compatibility and economic efficiency of geothermal energy in general. The geological setting in Groß Schönebeck is typical of the North German Basin and belongs to a geological structure which extends across much of West and Central Europe, and the results obtained are expected to be transferable to many other locations within the Basin. 

In 2002 two fracturing operations were performed in two different intervals of the E GrSk3/90 well, applying proppants and gel.  A major water fracturing treatment was then conducted over the complete open hole section. These stimulations led to a significant improvement of the productivity of the well. In the second well (Gt GrSk 4/05), three stimulation operations were carried out successfully in two different formations (volcanic rocks and sandstone) in 2007. After water and proppant fracking, a circulation test between the wells characterised the doublet under realistic conditions, with the original well being used as the injection well. A geothermal research power plant has been set up in 2010 to test and improve cost-effectiveness and energy efficiency.

Groß Schönebeck has been one of the test sites of the EU-project I-GET (Integrated Geophysical Exploration Technologies for deep fractured geothermal systems), where geothermal exploration techniques have been developed to increase the success rate of drilling.

Indicative papers:

  • Huenges, E., Trautwein, U., Legarth, B., Zimmermann, G., 2006. Fluid pressure variation in a sedimentary geothermal reservoir in the North German basin: Case study Groß Schönebeck. Pure Appl. Geophys. 163, 2141-2152.
  • Blöcher, G., Reinsch, T., Henninges, J., Milsch, H., Regenspurg, S., Kummerow, J., Francke, H., Kranz, S., Saadat, A., Zimmermann, G., Huenges, E., 2016. Hydraulic history and current state of the deep geothermal reservoir Groß Schönebeck. Geothermics 63, 27-43.

More details about the Groβ Schönebeck GeoEnergy Test Bed can be found at http://www.gfz-potsdam.de/en/scientific-infrastructure/laboratories/gross-schoenebeck/.


 


There are more facilities to come, we are currently in discussion with these facilities about engaging them in the TCS. We would be extremely happy to hear about other facilities that would like to engage.