Laboratory of Aquaculture & Artemia Reference Center, Ghent University, Ghent, Belgium.
Email: andclerc.declercq@ugent.be
Offshore wind farms provide a unique opportunity to combine renewable energy production with sustainable food provision and ecosystem restoration. Belgium is pioneering this approach through integrated multi-use pilots that bring seaweed cultivation, shellfish aquaculture, and habitat enhancement into practice within offshore wind concessions, with a strong focus on industrial scalability.
Within the Horizon Europe project ULTFARMS, we developed and tested a novel submersible longline system for seaweed cultivation. The patented variable-buoyancy structure allows nets to be raised and lowered depending on hydrodynamic conditions. Trials demonstrated that submergence reduces storm impacts while still enabling robust growth of Saccharina and Alaria. We will show how these prototypes have been operated successfully at sea and how scaling scenarios indicate production potentials of 25–30 tonnes fresh weight per hectare per year with competitive CAPEX/OPEX profiles.
In parallel, acoustic monitoring of dropper lines using multibeam sonar was piloted to quantify mussel biomass and gear condition in real time. The first trials delivered reliable estimates of biomass accumulation and structural integrity under offshore conditions. These results demonstrate the potential of acoustic monitoring to support the operational management of shellfish culture, and we will show how this approach is being advanced toward practical application at larger scale.
Finally, through the Reefcovery and Horizon Europe Blue Connect projects, we have successfully settled the European flat oyster (Ostrea edulis) on rock substrates in hatchery and mobile on-land systems. These trials show that spat-on-substrate production is feasible at scale, and we are now preparing deployment on wind farm scour protection and cable crossings. We will present how these first steps are being translated into practical pathways for large-scale offshore restoration in collaboration with industry.
Together, these advances show how offshore wind farms can be transformed into multi-use platforms, generating renewable energy, seafood, and restored marine ecosystems. The Belgian case demonstrates that with technological innovation, monitoring integration, and industry partnerships, industrial-scale offshore multi-use is moving from concept to practice.
Keywords: multi-use, offshore wind farms, seaweed, mussel, oyster, restoration, aquaculture