Offshore wind farms provide an ideal environment for cultivating seaweed in the North Sea for use as biomass fuel, concludes a study published by the Energy Centre of the Netherlands (ECN). Commercial seaweed cultivation systems usually consist of anchored line structures to which the seaweed is attached, generally at coastal locations. International research shows that cultivation systems in the open sea may become easily damaged by wind and wave action. Supports for offshore wind turbines, however, could serve as a structural basis for seaweed cultivation systems far out to sea. Their construction would have to take into account the additional loading from the seaweed and accessibility for harvesting. There are potential synergistic effects through combining offshore wind and seaweed cultivation that support the profitability of both activities, including joint management and maintenance, alternative employment opportunities for fisheries and ecological benefits, says ECN. But considerable development is needed to enable large scale, economically attractive cultivation of seaweed at offshore wind farms. Seaweed productivity in the North Sea is estimated at about 20 tonnes of dry matter per hectare a year, which could be increased to around 50 tonnes per hectare. The Dutch government's target for offshore wind in 2020, 6000 MW, involves a surface area of approximately 1000 square kilometres.