Germany’s seawater heat pump begins supply
18th September 2026
GERMANY: Germany’s first seawater heat pump supplying heat into a district heating network has been officially inaugurated after several months of trials.
The water is taken from the Baltic Sea to warm the connected residential buildings, commercial properties, and public buildings in the harbour district of Neustadt in Holstein.
The system consists of an extraction station at the harbour basin, an energy centre, and the approximately 2km-long heating network. At the intake station, seawater is drawn, filtered, purified, and pumped to the energy centre.
The energy centre contains the Johnson Controls’ 700kW Sabroe DualPAC ammonia heat pump, the heat exchanger and a 25,000 litre buffer storage tank. The heat exchanger transfers the heat contained in the seawater to a separate glycol circuit, where the heat pump raises the temperature to 70ºC.
Addressing guests at the inauguration ceremony, Dr Mark Jahn, managing director of the Neustadt in Holstein municipal utility company, said: “The seawater heat pump is an outstanding example of what is possible when courage to embrace new technologies, technical expertise, and the collaboration of many stakeholders come together.”
Following the trials, the system is now commencing regular heat supply.
