Socio-Economic Assessment of Co-Located Offshore Wind and Aquaculture Systems

With the ongoing energy transition towards renewable energy and away from nuclear power, offshore wind energy has become increasingly important and now represents a central pillar of German energy policy. Consequently, a growing number of offshore wind farms are being constructed in the North Sea. This development renders large marine areas unavailable for traditional activities such as fisheries and other former economic uses, while the water column in the immediate vicinity of the monopile foundations remains largely unused by other sectors. Monopiles interact with the local hydrodynamic environment by modifying wave propagation and attenuating wave energy, yet they do not adversely affect water quality, making these areas potentially suitable for co-use applications, such as offshore aquaculture. For lower-trophic aquaculture, essential nutrients are naturally supplied by the marine environment, and the demand for mussels and macroalgae as food resources is steadily increasing. However, aquaculture production in Germany has so far been dominated by onshore and near-coastal facilities, with offshore cultivation still being limited.

In this study, the socio-economic system (SES) formed by the co-location of an offshore wind farm and aquaculture is analysed using the Ostrom–McGinnis framework. The analysis focuses on the existing offshore wind farm Meerwind, located northeast of Helgoland, which enables the assessment of OWF impacts on the SES based on historical and observational data. This framework allows for the systematic evaluation of how public benefits can be optimised, in particular by enhancing the ecosystem services and socio-economic value generated by offshore aquaculture. By varying and analysing key conditions, such as the precise spatial placement of aquaculture installations, optimal configurations of the SES can be identified. The drivers and feedbacks influencing the SES are quantified using numerical simulations. For this purpose, the hydrodynamic model SCHISM is coupled with the biogeochemical model ECOSMO to simulate environmental conditions relevant for aquaculture growth and to explicitly model mussel production. This integrated modelling approach enables the estimation of public benefits under different SES configurations, thereby providing a quantitative basis for advising industry and policymakers on sustainable co-use strategies within offshore wind farms.