Water heat pumps are becoming increasingly important in the context of the decarbonisation of the heating sector. However, there is still considerable uncertainty, particularly regarding their impact on nature conservation. The new BfN publication addresses these uncertainties and provides an assessment of the trend towards expansion, the technical implementation options and the legal aspects. Initial approaches to ensuring environmentally sound design are outlined.
The paper presents trends, forecasts the implications for nature conservation, outlines the legal framework and identifies implementation options. The authors conclude that water-source heat pumps can have negative impacts on aquatic ecosystems, particularly through land use, trapping effects and localised cooling of water bodies. However, there are still significant uncertainties regarding legal and aquatic ecological aspects. The need for ongoing monitoring during operations to improve our understanding is emphasised.
BfN-Schriften 775: Gewässerwärmepumpen – Trends, Auswirkungen und naturschutzfachliche Relevanz - Sachverständigengutachten. Henrik Pieper, Jannika E. Maaß-Schoon, Johanna Schickling, Jörg Rassmus, Jan Laurenz-Nickel, Jasmin Franz, Nele Wotha, Daniel Kapteina. BfN-Schriften, 2026 (includes an abstract in English)