Thermos flask for Munich district heating on the grid
Stadtwerke München has commissioned its new 50-metre-high heat storage facility at the southern combined heat and power plant, thereby increasing flexibility and security of supply in the district heating network
12.05.2026
Source: E & M powernews
Two and a half years after construction began, Stadtwerke München has put its 50-metre-high heat storage facility into operation at the Süd energy site.
The heat storage facility of Münchner Stadtwerke (SWM) at the Süd combined heat and power plant looks like a gigantic thermos flask. It was connected to the district heating network in April, as the company announced on May 11. The system will be further optimized during trial operation. It is already connected to the city center and Perlach district heating networks.
"The commissioning of the connection for the Sendling network is being prepared," SWM announced. With a height of 50 meters and a diameter of around 40 meters, the heat storage tank has a gross capacity of around 57,000 cubic meters of district heating water.
Important building block for the heat transition
The heat storage tank is an important building block for SWM in the successful implementation of the heat transition. It allows the energy generation plants at the southern site to be made more flexible. Electricity and heat generation at the HKW Süd could be decoupled more efficiently, explains SWM.
If a lot of electricity is needed but little heat, the surplus heat can now be stored. If, on the other hand, little electricity is needed from the power plant - for example, because there is a lot of electricity from renewable energy sources in the grid - and production is throttled back, less heat is also generated. The heat in the storage system can then be used.
"In the future, the storage facility can also temporarily store the heat from the geothermal plant at times of low load and release it again when there is a high demand for heat," says SWM. All of this creates greater efficiency in the overall system and strengthens the city's security of supply.
Traditional energy site undergoing change
SWM's southern energy site specifically stands for the transition from the old to the new energy world: electricity has been generated here for the city since 1899. After phases with coal and waste incineration, combined heat and power (CHP) based on natural gas has been the state of the art for a quarter of a century.
"The future belongs to renewable energies," plan SWM. Germany's largest geothermal plant, which can supply green heat for around 80,000 people, is already in operation on the north side of the energy site.
In future, a district cooling center will supply climate-friendly district cooling to the city center in order to meet the growing demand there. In the HKW Süd itself, biomethane or hydrogen could be used proportionately in future through the use of state-of-the-art technology in order to use less fossil fuels, according to further plans.
Author: Susanne Harmsen