Non-Contact Inspection Methods for Wind Turbine Blade Maintenance: Techno–Economic Review of Techniques for Integration with Industry 4.0

Wind energy has emerged as a critical source of renewable energy worldwide, and the performance of wind turbines relies heavily on the quality and design of their blades. However, the manual manufacturing process of wind turbine blades using polymeric matrix composite materials makes them susceptible to irregular and complex loading damage. This damage can lead to reduced power generation, shortened lifespan, and increased maintenance costs. Therefore, non-destructive testing (NDT) of wind turbine blades is necessary to identify surface and internal defects, ensuring the sustainable operation of the wind turbines. This article briefly reviews wind turbine blades' materials, design, and manufacturing methodology. We also discuss the inspection strategy during production and inspection methods during operation. Five non-contact NDT techniques, including thermography, radiography, machine vision, laser shearography testing, and microwave testing, are appraised to inspect wind turbine blade damage. These techniques were evaluated using a Techno–Economic approach that considers technical and economic factors, such as accuracy, cost, reliability, and ease of implementation. Thanks to technological advancements, integrating non-contact inspection methods with Industry 4.0 technologies can help improve wind power generation's safety, efficiency, and reliability. However, evaluating available methods' compatibility with Industry 4.0 technologies may be necessary.