June 22, 2009 | News
The German Ministry of Economics and Technology carries out research with the Herrenknecht Vertical “InnovaRig” in Hannover.
The German Ministry of Economics and Technology (BMWi) is financing the “GeneSys” pilot project in Hanover, Germany. This project aims to prove that office and laboratory buildings the size of the research center for geosciences can be heated very economically. Geothermal power of 2MW is necessary for the heating, requiring flow rates of 25m³/h and a conveyance temperature of 130°. Normally, two wells are needed for this procedure. The Hanover project aims to prove that this is also possible using a concept based on a single bore hole, thus reducing the payback period of the project. In addition to the financial aspect, the project also aims to show the technical possibilities in dense sediments.
The Herrenknecht Vertical “InnovaRig" Terra Invader TI-350 type deep drilling rig is being used for the deep drilling procedure. This machine has already proven itself in the geothermal energy project in Dürrnhaar in Bavaria. The noted drilling company H. Anger’s Söhne is once again responsible for drilling. With the TI-350, the company was already able to achieve an excellent drilling performance in Dürrnhaar. The machine will bore through sediment layers from the Cretaceous, Jurassic and Triassic periods down to a depth of 4,200 meters.
Hanover was chosen as a site with sediment formations typical of northern Germany. The target sediment is the middle bunter sandstone at a depth between 3,700 and 4,000 meters with temperatures between 130° and 160°C. The usual thermal water exploitation is very difficult in this layer, so that a heat exchanger is created by artificial cracks. The hot water is then fed into the heating circuit via an aboveground heat exchanger, and the cooled water is subsequently pressed into a higher layer. The efficiency of the system will be demonstrated during a trial operation over several months, thus encouraging the breakthrough of the use of geothermal energy in northern Germany.
