Comparison Study of Shallow Water and Deepwater Dynamic Power Cable Systems for Floating Offshore Substation

Abstract As offshore wind lease areas extend further from shore to harness more wind energy resources, they also progress into deeper waters. Water depth plays a crucial role in the feasibility of Floating Offshore Substation (FOSS) projects due to the cost implications of dynamic power cables. This study presents a comprehensive comparison of shallow water and deepwater power cable systems, including Inter-Array Cables (IACs) and export cables, for two different water depths. To conduct this comparison, two mooring systems and a semisubmersible floating platform were designed for 1000 m and 300 m water depths, respectively, for a 750 MW capacity FOSS. The study was conducted for both survival and operational design load cases, with multiple realizations to obtain reliable statistical results for the fully coupled FOSS system responses. The conclusions discuss the governing design parameters of dynamic power cables for different water depths, as well as the responses of the FOSS hull and mooring system.