Wind turbines face erosion at the leading edge of the rotor blades. This issue becomes more complex as turbines grow in size and are increasingly deployed offshore. One of the most promising solutions to this problem comes from an unexpected corner: textiles.
Leading Edge Erosion on Wind Turbine Blades
Erosion at the leading edge of the rotor blade (leading edge erosion) is one of the most critical issues for wind turbine blades. This phenomenon warrants extra attention because it has significant consequences for both energy output and service life. There are multiple causes of erosion, and they become more complex due to several evolving trends:
- Increasing rotor diameter – Larger turbines have higher tip speeds, which exacerbate the erosion issue on the blades.
- Offshore wind farms – Offshore turbines are exposed to harsher weather conditions and require more maintenance, while access at sea is more difficult and thus more expensive.
- Service life expectations – Modern wind farms are designed for a lifespan of 25–30 years, which demands more from the durability of materials.
Causes of Leading Edge Erosion
Weather conditions are the main cause of leading edge erosion:
- Raindrop impact – Tip speeds can exceed 300 km/h. The larger the turbine diameter, the higher the speed. As a result, raindrops strike the leading edge at high velocity, and each drop’s impact causes slight stress in the material. The accumulation of droplets causes a build-up of stress that the rigid material of the turbine blade can eventually no longer absorb, leading to cracking.
- Dust and sand particles – Particularly in offshore or desert-like environments, small particles can act like sandpaper on the blade surface.
- Hail, ice, lightning – Harder precipitation causes more immediate damage to the surface. Lightning strikes, in particular, can have massive consequences.
- Salt water and UV radiation – In offshore wind turbines, salt accelerates the erosion process. UV radiation also has a major impact, as it degrades the resin in composite materials, causing them to break down over time.
The effects of edge erosion range from significantly reduced energy output to premature material failure, with infiltration and structural weakening as a result. This typically leads to increased maintenance costs and sometimes early blade replacement.
“In our lab, we simulated the impact of environmental conditions using every means at our disposal. Through trial and error, we worked our way towards a solution, which we found in a kind of textile sleeve that is stretched over the turbine blades.”
Why Technical Textiles Could Offer a Solution
This issue illustrates how seemingly minor surface problems can have major implications for the economic viability of wind energy. This explains why considerable R&D investment is going into materials science and surface technology for turbine blades.
Textiles have recently gained momentum in surface technology. When the Scottish engineering firm ACT Blade approached the Belgian company Concordia Textiles, the solution wasn’t immediately obvious. Rik Gekiere, Business Unit Manager ICA at Concordia, explains:
“In our lab, we simulated the impact of environmental conditions using every means at our disposal. Through trial and error, we worked our way towards a solution, which we found in a kind of textile sleeve that is stretched over the turbine blades.”
The blades are made with a specially designed rib structure that makes the entire assembly much lighter. The base textile is coated with a protective film, formulated to enhance the properties of the textile without degrading them. The design is now protected and has been named ZephyrTM.
Zephyr™ for the Next Generation of Wind Turbines
Expectations for Zephyr™ are high. The Scottish blade manufacturer ACT Blade is the first to integrate Zephyr™ into its manufacturing process. The expectation is that Zephyr™ will lead to significant savings in blade maintenance costs—thanks to the power of textiles.
- Textiles are, for many reasons, the ideal solution in surface technology.
- Textiles are lightweight, flexible, and impact-resistant, and they have excellent fatigue properties.
- Textiles offer strength in multiple directions, are shrink-resistant and resistant to delamination. Since they can combine different fibre types, they are also an excellent base for composites.
Finally, textiles can be mass-produced and are easy to repair.
