Strabag to build world’s largest heat pump in Germany

Strabag’s Umwelttechnik division will build the river-source heat pump at the Grosskraftwerk Mannheim (GKM) power plant site in southwest Germany.

From left to right: Thomas Büchner, managing director of STRABAG Umwelttechnik; Dr. Gabriël Clemens, CEO of MVV; Christian Sadleder, Strabag Austria, head of energy infrastructure; Thomas Hörtinger, CTO of GKM; Dr. Hansjörg Roll, CTO of MVV

The Mannheim-based energy company MVV Energie AG is investing up to €200 million in the project, which will supply climate-friendly district heat to as many as 40,000 households in the Rhine-Neckar metropolitan area. Construction is expected to start in mid-2026, with commissioning scheduled for winter 2028.

The installation will consist of two modules, each providing 82.5 MW of output, together delivering 165 MW. Using Rhine river water as a heat source and the natural refrigerant isobutane, the system will generate district heating water at temperatures up to 130°C.

Funded under Germany’s federal programme for efficient heating networks (BEW), the project is part of MVV’s goal to fully decarbonise Mannheim’s district heating supply by 2030.

MVV chief technical officer Dr Hansjörg Roll said, “Thanks to energy from thermal waste treatment, our biomass combined heat and power plant, and the first river-source heat pump, we are already able to cover nearly 50 percent of our district heating needs from renewable sources.”

Strabag will deliver the project using its in-house design-and-build expertise in industrial plant engineering, supported by its Heat Pump Alliance partnership with Atlas Copco Energas. The system’s core technology relies on Atlas Copco’s turbo compressors, used in more than 7,000 applications worldwide.

Strabag CEO Stefan Kratochwill said, “The Mannheim contract strengthens our position as a partner for future-oriented, climate-neutral water and energy infrastructure. We are proud to be working with MVV to make an active contribution to the decarbonisation of urban heating and energy supply.”