|The GeneSys-Project: Coast Efficient Single-Well-Concepts for Deep Geothermal Energy from the Northern German Basin.
Within the GeneSys-Project, the BGR (Federal Institute for Geosciense and
Resources) and GGA-Institute (Leibnitz Institute for Applied Geosciense) aim at
the extraction of deep geothermal energy (3500-4000 m) from the tight
sediments of the Northern German Basin. Therefore three new concepts for
geothermal heat extraction using a single-well-concept have been developed,
since drilling costs are a crucial point to the efficiency of geothermal plants.
All concepts have been developed for the use in low-permeable sediments to
provide small to medium-sized consumers with geothermal heat in the order of
2 MWth. Key technology to all concepts is the water-frac-technique, which is
used to create large fractures in the sedimentary rocks.
- Deep circulation concept: Via a hydraulic fracture a highly permeable geologic
fault is connected to the well. Hot water can be withdrawn from the formation.
- “Huff-Puff”-concept: A hydraulic fracture is created, which acts as a storage
reservoir for injected cold water. The cold water heats-up and can be produced
as necessary. The cycles of injection and production can be adapted to the
needs of the consumer – e.g. injection during weekend and production during
working days or injection in summer and production in winter.
- Two-strata concept: A hydraulic fracture connects two strata of sandstones.
Both strata are connected to the well. A tubing passing a packer gives access
to the lower stratum while the upper stratum is linked via the annulus of the
same well. Water is injected into the lower sandstone, heats-up while migrating
through the fracture and is produced from the upper sandstone layer. A
persisting circulation is established.
The Huff-Puff and the Two-Strata concept have been successfully applied at the
geothermal research well Horstberg Z1 in the Mittlere Buntsandstein formation.
By the end of 2007 a 3800 m deep well will be drilled in the town of Hannover
to supply office and laboratory buildings of the GEOZENRUM with geothermal
heat by using a coast efficient single-well concept.
Iceland Room: Vidgelmir
||Mr. JUNKER, Ralf (GGA-Institut)
||Dr. TISCHNER, Torsten (BGR)
Prof. KEHRER, Peter (BGR)
Mr. JATHO, Reiner (BGR)
Mr. WESSLING, Stefan (GGA-Institut)
Mr. HOFMEISTER, Knut (BGR)
Mr. EVERS, Hermann (BGR)
Mr. SULZBACHER, Hans (GGA-Institut)
||Mr. JUNKER, Ralf