
From Finspong in Sweden to Mannheim in Germany: First MVV heat pump reaches its destination
Transportation of around 1,400 kilometres on several trucks from the Siemens Energy production site in Sweden to the GKM power plant in Mannheim - Important milestone on the way to green district heating in Mannheim - Commissioning on schedule in autumn 2023
The large-scale heat pump will help MVV to decarbonize district heating in Mannheim
Together with MVV we are building a large-scale heat pump plant in Mannheim. It will use river water as a heat source, helping to reduce the use of coal at the GKM plant. The new heat pump is the first step towards the goal of green district heating. MVV and the City of Mannheim is targeting to become CO2 neutral in the district heating production by 2030.At the Mannheim site, the heat pump uses 7 MW of electrical power from renewable sources to produce 20 MW of thermal energy which is used to reheat the district heating return flow up to 99 °C. From 2023 onwards, the facility is expected to supply heating for 3,500 households and save some 10,000 tonnes of carbon emissions per year.
The heat pump power plant consists of the following components
The proven Omnivise T3000 control system integrates the control of the new heat pump and an existing thermal storage into the existing GKM power plant. The control system uses its multi-unit functionality to manage multiple generation units from a central control room. Omnivise T3000 is also a control solution for hybrid power plants. It can manage a variety of different distributed energy resources in an automated, autonomous, and coordinated manner, ensuring reliable 24/7 operation. At the same time, it is flexible and scalable to support larger numbers of assets if required.
This new type of large-scale, high-temperature heat pump provide thermal capacity of up to 20 MW, which will be capable of flexibly delivering flow temperatures in the district heating network of between 85°C and about 99°C, depending on ambient conditions. This is one way in which technology make a further contribution toward replacing fossil-based heating in urban district heating networks of Mannheim and the region. In addition to more efficiently linking energy resources at the GKM site and MVV's other generation units, the project serves to test the large-scale heat pump in Germany for the first time on a practical scale under real conditions.
The Rhine water pump for the heat pump system is installed in the cooling water pump house of unit 7. The Rhine water pump extracts max. 700l/s of water from the river as a natural heat source to supply the new river water pump with the environmental renewable energy for heating the district heating water. The Rhine water is cooled by approx. 2 to 5 °C.
With the district heating storage (1,500 MWh heat capacity), we are increasing the flexibility and security of supply for the district heating network in the Rhine/Neckar metropolitan region. Similar to a thermos flask, the storage facility is loaded and unloaded as required, allowing us to respond flexibly to fluctuating demand. The plant was designed and built by GKM on behalf of MVV Energie and, depending on operating conditions, can secure the entire district heating supply of the region for several hours.
Water protection is ensured through environmentally friendly water intake and discharge. Both structures are designed in such a way that they do not have a negative impact on the flow conditions in the river, either for flora and fauna or for navigation. The intake structure is deep enough to ensure a constant supply of river water to the heat pump, even when the river level is low. The structures did not need to be rebuilt but can be used in their current form. This saves resources and avoids additional environmental impact.
More than two-thirds of households in Mannheim and the neighboring cities of Heidelberg, Schwetzingen, Brühl, Ketsch and Speyer will benefit from environmentally friendly district heating in the future. The river heat pump, which GKM is integrating into the large-scale heat pump system for MVV, will supply approximately 3,500 households with green heating from 2023. This will save around 10,000 tons of CO2 per year.
The heat pump service contract is based on continuous data exchange, which enables to perform remote inspection and service experts to plan inspection-based or remote analysis.
The analysis is based on the experience from 50 heat pump installations with more than 6 million operating hours. The service contract includes operational service desk, which means service experts will provide 24/7 support.
These experts can resolve problems even faster by analyzing historical data from connected heat pumps. Using online technical support, they can provide over-the-shoulder assistance and remote guidance. If more support is needed, a network of specialists is available to provide emergency spare parts or rapid deployment of field service personnel.
Basic principle of heat pumps
Heat pumps move thermal energy in the opposite direction of spontaneous heat transfer, by absorbing heat from a colder space and releasing it to a warmer one.

Learn more about the MVV Mannheim reference in Germany
District heating for 50,000 households – with heat pump technology from Finspong in Sweden
The heart of the heat pump plant is the compressor with gear, electrical motor, heat exchangers, and control system. The reliable heat pump is manufactured in our factory in Finspong, Sweden, and Siemens Energy is responsible for the full installation and commissioning. The technology has been proven for many years.From the ground-breaking ceremony to the final heat pump plant
In spring 2022, the next step in our decarbonization journey began with the construction of our 18-metre-long, five-metre-high high-temperature heat pump on the site of the GKM coal-fired power plant. Commercial operation will start in 2023. It is one of five large-scale field trials - called 'Reallabore' in German - for large-scale heat pumps in Germany, using different heat sources such as industrial waste heat, geothermal or solar energy, river water, the sea, ambient air and others."Decarbonisation of heat is not only urgent in order to reach net-zero emissions by the middle of the century, it is also imperative to achieve security of energy supply in geopolitical uncertain times."Dr. Christian Huettl, VP, Global Head of Heat Pumps, Siemens Energy