For mussels (Mytilus edulis) and oysters (Crassostrea gigas, Ostrea edulis) several types of cultivation can be used in the North Sea region. Predominately, longline constructions are proposed for the cultivation of bivalves, by which submersible ropes provide the habitat on which the candidates can settle (Fig. 5 & 6). Other techniques, such as ring and cage constructions, which can be placed on the water surface and under water, as well as the construction SOSSEC (Submersible Offshore Shellfish and Seaweed Cage) can be operated, too. For seaweed (Saccharina latissima (Laminaria saccharina), Palmaria palmata) cultivation seedlings will be raised on ropes (Fig. 7) under lab conditions and later fixed to floating or submersed ring constructions (Fig. 8).
The advantage of submersible culture constructions are the avoidance of the impact of harsh weather conditions and strong wave mechanics. Thus, a combination of these techniques with the main pillar (tripod or jacket) of the windmill installation dispenses the need for a sophisticated and expensive mooring of the aquaculture system, which would also impact strongly on the benthic ecosystem. Due to the solid construction of the windmills, such systems would be very stable fixed (Fig. 9).