Successfully integrating large-scale heat pumps into existing power station sites

Large-scale heat pumps are a key technology for the decarbonisation of district heating. However, it is not the technology alone that is crucial to the project’s success, but above all its safe and reliable integration into existing infrastructure.

The WPA2 project at the Grosskraftwerk Mannheim demonstrates just how complex this task is. In his technical article for the vgbe energy journal, Dr Olaf Thun, Project Manager for Energy and Heat Supply at INP Deutschland, explains the key technical, planning and organisational requirements from the perspective of the lead planner.

Two large-scale heat pumps with a combined thermal output of 165 MW

At the site of the Grosskraftwerk Mannheim, MVV is constructing a large-scale heat pump plant that utilises water from the Rhine as a renewable heat source. The project involves two heat pumps, each with a thermal output of up to 82.5 MW. Together, they will achieve a total output of 165 MWth. The heat generated will be fed into the district heating network at a maximum flow temperature of 130 °C.

The main challenge lies in integrating the new plant into the existing waterways, district heating systems, high- and medium-voltage installations, the control systems, and into existing operational, safety and construction procedures.

General planning brings together all specialist disciplines

In a project of this scale, process engineering, electrical and control engineering, construction, planning for regulatory approvals and commissioning must be considered jointly from the outset. In addition to the technical components, factors such as site availability, water extraction, electrical power, deadlines, costs, lead times and future maintenance also play a key role.

As the lead designer, INP Deutschland is overseeing the planning and implementation of the project. The tasks range from feasibility studies and preliminary planning, through tendering, contract award and planning for regulatory approvals, to the coordination of construction, installation, commissioning, trial operation and final acceptance.

The article makes it clear that standardised technology does not automatically result in a standardised plant. Only through consistent planning and coordination of all interfaces can an integrated system be created that is safe, reliable and capable of being permanently integrated into the existing power station operations.

The full technical article, ‘Integration of large-scale heat pumps at power station sites from the perspective of the general planner – a practical example: WPA2 at the Mannheim large-scale power station’, has been published in issue 8/2026 of the vgbe energy journal.