Neustadt in Holstein inaugurates Germany’s first seawater heat pump

Stadtwerke Neustadt in Holstein has inaugurated Germany’s first seawater heat pump integrated into a district heating network. The facility, manufactured by Johnson Controls, extracts heat from the Baltic Sea to supply more than 200 households in the harbor district.

The Sabroe DualPAC system utilizes a two-stage process with two compressors to achieve a flow temperature of 72 degrees Celsius. It operates with a performance coefficient of over three, meaning it produces more heat than the electricity it consumes. Technicians noted that the system remains efficient because seawater cools more slowly than air, maintaining higher temperatures during winter months.

The project, which originated as an idea in 2012, received funding through the federal “Wärmenetze 4.0” program. Schleswig-Holstein’s Energy Transition Minister, Tobias Goldschmidt, attended the inauguration, suggesting that other municipalities might look to the Neustadt model for their own heating plans.