Specificities of floating offshore wind turbines for risk and safety evaluation of anchoring systems
Specificities of floating offshore wind turbines for risk and safety evaluation of anchoring systems
Floating offshore wind turbines (FWT) are still in their infancy and represent only 0.2% of currently installed commercial offshore wind capacity (193 MW of 65 GW) but will be critical to achieve net-zero objectives by 2050. The design of mooring systems and anchors for FWTs relies heavily on established Oil and Gas (O&G) practice, although governed by different design requirements. Reassessment and refinement of anchor system design methods and practices is necessary, recognising the different risks from FWT failure and the imperative for mass-production within the next 25 years. This paper identifies first the main differences between floating O&G and FWT and the associated geotechnical challenges and risks; then four key developments relevant to industry needs are selected and the solutions to reduce risk and uncertainty are then detailed: (i) Shared anchors; (ii) Farm-wide reliability assessment; (iii) Whole-life geotechnical design; and (iv) Screw pile installation. These examples show how physical, numerical and theoretical modelling can compensate for the current lack of FWT field experience to reduce design risk and raise project viability. Finally, technical project-wide risk is put into perspective by a comparison with the planet-wide risk resulting from delayed offshore wind farm installation.