COST-EFFICIENT OPTIMIZATION OF SYNTHETIC MOORING SYSTEMS WITH POLYMER SPRINGS FOR 15 MW FLOATING WIND TURBINES IN SHALLOW WATERS

The deployment of larger wind turbines has significantly reduced energy costs but has also introduced new challenges for installations in intermediate water depths (50–150 m), where efficient mooring systems are critical. While traditional chain catenary arrangements and polyester-based solutions are widely used, they often fail to adequately mitigate peak loads or maintain platform pitch control, particularly under extreme environmental conditions. Nylon has emerged as a promising mooring material due to its inherent elasticity, which effectively reduces peak loading. However, its use can lead to increased platform pitch and may raise concerns about long-term fatigue performance. To address these issues, recent optimization frameworks have focused on hybrid nylon-chain systems, fine-tuning parameters such as line length and diameter. The integration of Load Reduction Devices (LDRs), tailored in length, target load, and stiffness, further enhances mooring performance by mitigating peak loads and fatigue damage while preserving platform stability and compliance. In this study, an LDR-nylon-chain mooring system was optimized to minimize both LDR length and target load across various platform radii. The resulting configurations achieved substantial cost reductions without compromising motion performance requirements. Minor adjustments were required to ensure compliance with tension limits, and subsequent analyses revealed pronounced peaks in the system’s power spectrum—attributed to the LDR’s low damping characteristics—thus highlighting an area that warrants further refinement. Overall, this work provides valuable insights for designing cost-effective and reliable mooring systems in shallow water environments, thereby advancing safe and economical floating wind technology.