Renewable energies: Bringing wind power forward with PU resins

In an interview with K-MAG, Dirk Soontjens explains how Covestro is optimizing and redeveloping PU resins to eventually increase wind turbine productivity – and how their customers are included in this process. Ultimately, what is their biggest finding from the research conducted at the Wind Technology Center?

Just over a year ago, you put your wind technology center into operation. How can one picture it? Which different departments work together there?

Dirk Soontjens: We have a dedicated team at the Wind Technology Center that deals purely with the (further) development of our materials for wind turbines. These materials include coatings, resins for the rotor blades, edge protection for rotor blades made of films or elastomers, or cable breakage and bending protection made of elastomer materials.

A special focus at the Wind Technology Center in Leverkusen is on tests of the resin for rotor blades, which is tested and optimized together with customers.

You work here on the optimization and new development of PU resins. Where are the resins used in wind turbines? In what way are they particularly suitable for this?

Soontjens: The PU resins are used in rotor blades together with glass fibers as the "core" of the rotor blades to give them just the right mix of stability and flexibility and make them more productive – if our materials are used, wind turbines produce electricity more cheaply.

PU resins have several advantages. First, in combination with the vacuum infusion process (for which we also offer machines), they bond optimally and opaquely with the glass or carbon fibers, providing optimal stability and flexibility. Second, they react out faster, making rotor blade production up to 20 percent faster. Third, they reduce the manufacturing costs of rotor blades by up to 8 percent.

Which steps of material development can you realize at the Wind Technology Center?

Soontjens: From molecules to laboratory tests to smaller components or prototypes (but not complete blades) – this includes not only material development, but also process development and optimization for the production of components.

How does Covestro involve (potential) customers in the research process?

Soontjens: Customers can have many different material tests carried out by us. For our resins in particular, we offer various physical tests and stress tests on the stability, flexibility or flow properties of the resin under conditions specified by the customer.

This enables us to show the customer exactly how our material behaves under the conditions that are relevant to them, and also to make slight adjustments to the formulation if necessary. So here we work closely with our current and potential customers to offer tailor-made solutions.

Why is Covestro specializing in wind power with its technology center?

Soontjens: As a company, Covestro wants to become climate-neutral and is fully focused on circular economy. Converting all energy requirements to renewable energies is relevant for both. To ensure that large consumers like us always have enough green power, this must be massively expanded worldwide and be as efficient as possible. This in turn requires the right materials that make wind turbines more productive. Our materials offer these advantages – and with the massive market growth for wind energy, there is certainly corresponding sales and revenue for us as a company.

What do you think was the biggest insight that came out of the research at Covestro's Wind Technology Center?

Soontjens: That we can significantly reduce the process times and thus also the cycle times of the production of rotor blades and their components.