Analysis and Optimization of Wind Turbine Blade Repair Processes

This thesis analyses and optimizes the repair processes of wind turbine blades, focusing on onshore maintenance and its impact on technical performance, cost reduction, and environmental sustainability. Wind energy is a key pillar of the energy transition, yet blade deterioration remains a major challenge for reliability and lifecycle efficiency. The study examines damage typologies, repair methods, and material choices to define a structured approach to blade restoration that combines engineering accuracy and sustainability metrics. Structural repairs—such as scarf joints, core replacements, and trailing-edge restorations—restore up to 95% of the original mechanical strength, provided that surface preparation, adhesive selection, and curing parameters are rigorously controlled. Surface repairs, including polyurethane coatings and erosion tapes, restore aerodynamic efficiency and limit performance losses due to environmental wear. The use of UV-curable and thermoplastic resin systems allows field curing in less than one hour, significantly reducing downtime, labour, and energy consumption. Field data confirm that curing and humidity deviations can reduce fatigue life by over 40%, highlighting the importance of process control and technician certification under ISO 45001 and GWO standards. Economically, optimized repair and predictive maintenance strategies reduce O&M costs by 15–25%. From an environmental standpoint, each repair avoids 8–10 tonnes of composite waste and 15–20 tonnes of CO2-equivalent emissions, representing a 90–95% impact reduction compared to full blade replacement. The thesis concludes that repairing rather than replacing is not only a maintenance choice but a strategic action for circular engineering. Through predictive analytics, advanced materials, and standardized repair procedures, wind farms can extend asset life, reduce emissions, and enhance long-term competitiveness—transforming blade repair into a core enabler of a sustainable and decarbonized energy future.