SWM invested around 1 billion euros
Stadtwerke München (SWM) is expanding its geothermal plants and the associated grids. Further cooperations are also planned in the district of Munich.
District – Stadtwerke München (SWM) are significantly expanding the heat capacities of their deep geothermal systems. The utility company will invest around one billion euros in deep geothermal energy by the early 2030s. Helge-Uve Braun is technical director of SWM and president of the Bundesverband Geothermie eV. He sees a key to an independent heat supply in deep geothermal energy: “We will leverage enormous potential and want to develop geothermal heat with a thermal output of 400 to 450 megawatts by the early 1930s.” quarter of Munich’s total district heating requirement of 1800 megawatts.
In Kirchstockach, Dürrnhaar and Sauerlach SWM already own and operate a geothermal plant. “There the EEG-subsidized power generation is still in the foreground,” says Braun: “But these contracts will expire at the beginning of the 1930s, then we will produce 100 percent heat for Munich and for the connected district communities.”
“The capacities are sufficient”
SWM intends to expand each of the three sites from one to three drilling duplicates. In Kirchstockach, a second duplicate should be down by 2025. A 22-kilometer transport line is already being planned in the south-east. SWM supplies the neighboring communities with geothermal energy via this route and connects them to the Munich district heating network in the Perlach area. “The capacities are sufficient,” emphasizes Braun: “We don’t take anything away from the district, we supply it with it. If possible, we will make an offer to all interested customers.”
The expansion of the existing locations is the most economical way to increase capacity, explains Braun, “because we are having increasing problems finding locations in urban areas”. A piece of land the size of a soccer field is required for a geothermal plant. An absorption thermal power plant is connected to each system, and fiber optic cables are laid for each borehole in order to permanently monitor underground processes.
Together with “Erdwärme Grünwald” (EWG) and “Innovative Energie Pullach” (IEP), SWM is cooperating in the south to set up new geothermal systems and, if possible, to expand existing systems. Pullach is investing millions in grid expansion to become independent of fossil fuels. In cooperation with Pullach and Grünwald, the SWM also want to transport ecological heat from the Isar valley to the city via long connecting lines. The basis for the choice of new sites in the two municipalities are seismic surveys that have been carried out with the IEP and the EWG. “Where and when drilling is to be carried out is still being agreed,” says Braun. Expect a doublet to be established in Grünwald and Pullach by 2026/27.
SWM also want to explore the subsoil in the north of Munich and explore the power of geothermal reservoirs. “We want to persuade other geothermal operators to cooperate with us,” says Braun. There are also efforts to cooperate in the East. SWM has also put out feelers to the municipality of Unterföhring and its subsidiary Geovol. Here, however, the relationship is tense because of a controversial gas power plant at the HKW Nord site. “We have offered talks from our side and are staying tuned,” says Braun: “With the Geovol, we could imagine building a geothermal aquifer storage facility.” This would allow summer energy to be stored for the winter. However, it is still to be investigated how underground long-term heat storage can be realized.
Lots of room for improvement
In order to advance the heat transition, the President of the Federal Association of Geothermal Energy calls for the federal government to provide subsidies and secure financing. Approval procedures for line construction must be accelerated, says Braun. This is where politics and administration come into play. The utility companies are also hoping for help by providing geodata: “The investigations from oil and gas production would help us, which are often still in paper form in the archives.”
In Germany there are currently 42 deep geothermal systems producing 1.3 terawatts of heat per year. There is still a lot of room for improvement, emphasizes Helge-Uve Braun: “If politicians deliver what they announced in the coalition agreement, we will see potential for geothermal energy that delivers 550 terawatt hours per year. That’s a lot and corresponds to 25 percent of the heating requirement in Germany.”
More news from the district of Munich can be found here.