A Progressive Screening Approach for Mooring Configuration Selection: A Case Study of the Arven Offshore Wind Farm

Abstract The mooring system of a floating offshore wind turbine (FOWT) impacts both the capital and operational expenses. The future success of floating offshore wind is, therefore, dependent on finding optimum mooring system designs from the wide field of possibilities. This paper introduces a methodology to identify appropriate mooring systems with the lowest cost using Arven Offshore Wind Farm as a case study. The methodology employs a systematic screening pipeline, utilizing short-duration time domain simulations in OrcaFlex to assess mooring line systems’ suitability based on DNV-ST-0437 and DNV-ST-0119 compliant load cases. Through progressively more detailed simulations, the pipeline efficiently narrows down the field of mooring configurations, assessing design parameters in one tenth of the time of a full enumeration. This approach allows for the identification of a lowest-cost mooring system, highlighting the design trade-offs between cost and key design parameters. For the Arven case study, the methodology has identified a semi-taut three-line nylon system with 225 m anchor radius, 1200 kN pretension and a 192 mm line diameter as being the most efficient system. The outlined methodology provides a broadly applicable and efficient means to identify optimum mooring systems for diverse development sites worldwide.