Rotor Blades Made from Natural Fibers to Solve Recycling Problem

A research team at Kiel University of Applied Sciences is developing rotor blades made of flax and wood as an alternative to GRP and CFRP. A yacht builder is providing practical data for the stress tests.

The rotor blades of wind turbines are increasingly becoming a disposal problem: tens of thousands of tons of composite waste are generated worldwide every year because glass and carbon fiber materials are difficult to recycle. A research team at Kiel University of Applied Sciences (HAW) wants to change that—with a rotor blade made of natural fibers.

The project “Development of rotor blades for small wind turbines from natural materials” is investigating how flax, balsa wood, or paulownia could replace glass fiber-reinforced plastic. Funded by the Schleswig-Holstein Energy and Climate Protection Agency (EKSH), Professor Sten Böhme's team is initially testing the materials in simulations and wind tunnel tests.

Prototype for Small Wind Turbines

The practical partner is Kiel-based Nuebold Yachtbau GmbH, which has experience with natural fiber composites. The company manufactures the rotor blades in full size and tests them for bending and load capacity in accordance with DIN standards. The goal is to create a functional prototype for small wind turbines with a rotor area of less than 200 m².

The project has been running since October 2025 and is scheduled to continue until September 2027. Initial material tests are already underway in the HAW Kiel laboratory, with wind tunnel tests set to begin next year.

This is a partly automated translation of this german article.