Polyurethane infusion resins from Bayer MaterialScience are suitable for the industrial manufacture of complete rotor blades for wind turbines. This is the result of a recent project performed by the new wind power competence center in the Danish city of Otterup.
This steers and coordinates the company's global activities in this field. In the manufacture of the blades the resins are combined with fibers in a mold and form a very strong material composite. The finished rotor blades are sturdier, longer-lasting and more lightweight than those produced with the epoxy resins and unsaturated polyesters used previously.
However, the most important advantage is the greater process and cost efficiency. As polyurethane resins are more free-flowing than conventional materials, they spread better in the mold and can be processed more quickly. They also harden faster and under simplified conditions. Bayer MaterialScience is confident that automated manufacture of rotor blades with robots will also be possible.
Around a quarter of the total costs of a wind turbine are for the rotor blades alone (1). Reducing these costs is therefore a key driver in wind power development. “The use of polyurethane resins could reduce the cycle time per blade from 16 to 24 hours currently to seven to eight hours, thus significantly increasing productivity. We are working to cut the cycle time still further,” says Kim Harnow Klausen, head of the Bayer MaterialScience global wind power competence center.
With its new competence and development center for wind power, Bayer MaterialScience is strengthening its development portfolio for energy generation from renewable sources. The center's project teams have now built up a global network to develop effective and sustainable materials and technologies for wind power applications. After the successful production of a prototype blade in Asia, the company currently focuses on achieving the blade sizes common today.