Reference Mooring and Dynamic Cable Designs for Representative U.S. Floating Wind Farms: Article No. 120473

The U.S. offshore wind industry will require novel solutions for floating wind turbine mooring systems and power cables to suit the diverse range of U.S. site conditions. To contribute to reference designs that reflect that need, this article presents designs for the key depth-dependent components - mooring lines and dynamic cables - for a 15-megawatt semisubmersible floating wind turbine in three U.S. regions: Humboldt Bay, the Gulf of Maine, and the Gulf of Mexico. These regions have varied metocean conditions and water depths. The Humboldt mooring system is composed of taut polyester rope, designed for deep, 800-meter (m) water depths and significant current loading. The Gulf of Maine mooring design is an intermediate-depth (200-m) semitaut mooring system composed of chain and polyester rope. The Gulf of Mexico mooring design is a shallow-water catenary chain mooring system for 80-m depth. A lazy wave dynamic cable was also designed for each site, tuned to the offsets of the accompanying mooring system. The mooring and cable designs were initially optimized with a quasi-static tool, then dynamic time-domain simulations were used to check tension, fatigue, and curvature as applicable before iterating on the designs. The final mooring designs pass all ultimate and fatigue load requirements. The dynamic cable designs meet all tension and curvature requirements, in coupled mooring and cable simulations of the extreme cases. The presented mooring and cable designs provide the components that can be combined with existing platform and turbine designs to form full reference floating wind array designs for these U.S. regions.