IMPACTS: "Offshore Wind Farm Foundations as Artificial Reefs: The Devil is in the Detail" - Werner et al., 2024
Offshore wind farms are not only considered key technologies for the decarbonization of energy supply but are increasingly discussed in terms of their ecological co-benefits. In particular, the function of their foundations as artificial reefs opens up potential synergies between climate protection and biodiversity conservation. The article “Offshore Wind Farm Foundations as Artificial Reefs: The Devil is in the Detail” by Werner et al. (2024) provides pioneering empirical evidence on this subject and emphasizes that not all foundation types contribute equally to the promotion of marine biodiversity.
The study focuses on the Atlantic cod (Gadus morhua), a species of both ecological and economic importance whose populations in the southern North Sea are under considerable pressure. Using standardized sampling methods, the presence of cod near wind turbines with different foundation and protection structures was assessed: monopiles with rock or sandbag protection, as well as jacket foundations. The results show significantly higher catch rates near rock-protected monopiles – strong evidence of their enhanced habitat potential. Other foundation types, by contrast, exhibited no or only very limited attraction effects.
The authors argue that the small-scale heterogeneity of reef effects can be attributed to the specific microstructure of the foundations. Consequently, the ecological added value of offshore wind farms largely depends on the details of their structural design – hence “the devil is in the detail.” The study therefore calls for ecological fine-tuning in the planning phase of new offshore wind farms to maximize their potential contribution to marine conservation strategies.
With this work, Werner et al. make an important contribution to depolarizing the debate on offshore wind energy, biodiversity, and marine spatial planning. In addition, the article provides a valuable data basis for the integrative assessment of wind farm design in the context of sustainable ocean use.