Advanced fatigue assessment methods: The future of modern wind turbines

Affordable and clean energy is one of the Sustainable Development Goals of the UN and part of the Green Deal established by the European Union. To reach these ambitious goals the contribution of wind energy is already indispensable among the renewable energies. For the realization of future wind projects, economic aspects will gain more importance. The requirement for efficient use of materials will be essential for economical wind turbine towers. Advanced fatigue assessment methods, such as the Two Stage Model, enable the consideration of structural and material input parameters explicitly. The required characterization of cyclic material properties is derived by different methods, e.g. the incremental step test. In this paper, an alternative way to determine cyclic material properties of the base material, the heat affected zone and weld metal using the easy-to-use Hardness method is evaluated by a proof-of-concept study. The study proves the potential for advanced fatigue assessment methods.