Press release from the Danish Plastics Industry. Photo: Henrik Wagner

The Danish Plastics Industry has chosen Sebastian Hermansen as the winner of the Danish Composite Award 2025 for his PhD project on structural optimisation of composite materials in offshore wind turbine blades.

The award is presented by the Composite Section under the trade association Plastindustrien.  

Early strength test of the blades

In his Ph.D. Sebastian Hermansen has developed an advanced design tool that can help assess how the blade can cope with different loads early in the design phase of a wind turbine blade.

When engineers today develop new wind turbine blades, strength and durability are often only tested at the end of the process. But with Sebastian Hermansen's method, it is possible to assess much earlier in the design phase whether the blade can withstand the many millions of vibrations and loads it is exposed to in operation.

In this way, weak points can be discovered and corrected immediately, avoiding having to change the entire construction later in the process.

The result is both stronger and lighter blades as well as more efficient design work.

Optimisation as a driving force

Sebastian Hermansen says that he has been fascinated by the concept of optimization since he became familiar with it during his first year at the university – and it has been a common thread throughout his studies.

"Receiving the Danish Composite Award 2025 means a lot to me. Behind the thesis lie many early mornings, long days and bumps in the road. I see the award as a recognition of this hard work and yet another confirmation that it has been worth it to give 110% to reach the goal," he says.

The first time the method is used on composites

This is the first time that this type of advanced optimisation – which has previously only been used for metals – has been adapted to composite materials such as fibreglass, which is used in modern wind turbine blades.

This makes the project groundbreaking both in terms of research and industry.

The tool can automatically suggest how thick the layers of the different composite materials should be and which materials are best suited for the different areas of the blade.

Demanding method

Sebastian Hermansen explains that it is particularly challenging to design fatigue-resistant structures, as the understanding of the underlying physics is still immature.

"This means that you are dependent on many physical experiments to be able to make calculations on fatigue failure at all. Optimality refers to a quantifiable best possible result of a given model – and its application in structural design is particularly challenging because modern products such as wind turbine blades are extremely complex and weight-critical."

Sebastian Hermansen's work has been praised as "outstanding" by the assessment committee, and the method has already been tested on a more than 100-metre-long commercial wind turbine blade. The project is part of the research collaboration MADEBLADES between Aalborg University, LM Wind Power, AB Inventech and DTU Wind Energy.

Today, Sebastian Hermansen continues to work with the method as an industrial postdoc at Gurit Wind Systems.