Erosion not only compromises the integrity of the wind-turbine blade, but also impacts its aerodynamic efficiency, resulting in significant loss in annual energy production. This loss is compounded by costly downtime for turbine repairs. The best defense for operators is to ensure that blades are protected as much as possible against erosion from the get-go. 3M Wind Energy has extensive experience providing solutions designed to improve blade build, enhance aerodynamic efficiency and help protect against leading-edge erosion.

Studies have consistently shown that erosion can lead to a loss in annual energy production (AEP) of up to 20% in severe cases. The heart of the issue is the fact that wind blades come into contact with various elements in the air at rotation speeds of up to 250mph, leading to erosion in the form of pitting, gouging and delamination of the leading edge of the blade. 3M offers a wide portfolio of effective solutions to tackle these challenges.

Reliable protection tapes and coating

Wind protection tape is the product with one of the longest track records in the industry, and is based on similar tapes used to protect helicopter blades and aircraft radomes. The newest product, 3M wind protection tape 2.0, has a highly durable design for significant reduction of leading-edge erosion, and extended maintenance and service intervals, offering up to four times the performance of standard wind protection tape in laboratory testing. Its capabilities include maintaining efficiency, reducing downtime, extending the life of blades, and preventing leading-edge erosion.
Another good option for protecting blades is a polyurethane coating. Designed for toughness, the coating gives the blade the layer of defence needed to reduce damage caused by rain erosion, combined with effects of nature such as UV.

Epoxy and polyurethane fillers

Fillers play an important part in getting the final aerodynamic shape of the blade in production. 3M fillers are not only efficient with a fast cure time, but can also provide high performance against erosion when combined with 3M LEP.
When a blade is past the point of protection and needs repair, minor damage can be treated with fillers made of epoxy or polyurethane. Fillers can also be used to finish
and smooth blade surfaces during manufacturing. When selecting a filler, users should consider their needs for performance, cure time and application methods. A variety of products are available to suit a range of purposes, with prevention of leading-edge erosion a key strength.

Aerodynamic efficiency

Overall turbine performance can be improved using products designed for maximising aerodynamic efficiency. These products include:

  • Acrylic foam tape: acrylic foam tape is often an excellent alternative to liquid adhesives and mechanical fasteners for attaching items to a wind turbine. Key benefits are the high conformability and flexibility of the tape.
  • Vortex generators (VGs): recent innovations in VGs have helped these devices live up to their true potential. Usually made from metal or plastic, VGs are affixed to wind turbines to help airflow stay attached to the blade for a longer duration, which helps to increase efficiency. The main advantage of installing a VG is that it has the ability to deliver a 1-3% increase in AEP.

Conclusion

Turbine owners have more useful tools than ever before to ensure that wind turbines can withstand harsh conditions, achieving improved efficiency and reduced downtime. 3M solutions are an excellent starting point designed to help extract every watt of energy, making the turbine more efficient and thus helping to improve return on investment.