A Novel Logistical Approach for the Installation of Floating Wind Turbines

This study presents a comparative assessment of two installation methodologies, i.e., a conventional towing-based approach and the Nordic Wind installation concept, where fully assembled wind turbine generators are transported and installed using a dedicated installation vessel. A simulation-based logistics framework is developed to evaluate installation performance under realistic metocean conditions, incorporating operational limits, weather downtime, and vessel utilisation. The methodology combines response-based operability criteria with long-term hindcast data to quantify installation duration across multiple percentiles (P20, P50, and P90). The results show that both methods are sensitive to weather variability, with installation duration increasing significantly from favourable to adverse conditions. The Nordic Wind method achieves a substantial reduction in installation duration, typically of the order of 40–60%, primarily due to reduced offshore exposure and more efficient utilisation of workable weather windows. Under more challenging environmental conditions, both methods exhibit increased variability; however, the Nordic Wind method maintains shorter overall campaign durations. A time-dependent cost model demonstrates that installation duration is the dominant cost driver. Accordingly, the reduced campaign duration achieved by the Nordic Wind method leads to lower installation costs in most scenarios, while remaining competitive under more severe conditions. The proposed framework enables a consistent comparison of installation strategies by integrating operability analysis, logistics simulation, and cost assessment, providing a basis for optimising installation approaches in floating offshore wind projects.