Preliminary Sizing and Optimization of Semisubmersible Substructures for Future Generation Offshore Wind Turbines

Abstract

Several key development areas have been identified as having high potential for reducing the levelized cost of energy of offshore wind. Two of the most anticipated developments are future generation large wind turbines and the use of floating foundations. There is thus a need for developing large floating substructures that are capable of hosting future generation wind turbines. This work presents the preliminary sizing of two semi-submersible platforms for supporting a 25 MW turbine through a design space search using a simplified parametric analysis. Compared to simple theoretical upscaling, the substructures resulting from the proposed simplified parametric analysis have significantly lower steel mass and stiffer tower.