Circular Process for Reuse of Wind Turbine Poles as Secondary Raw Material

Abstract

The demand for secondary steel resources in industrialised countries will increase significantly in the future as resources become scarcer. A 2 MW wind turbine contains over 170 tons of steel, whereby these quantities usually migrate to eastern regions at the end of the wind turbine's service life. In addition, there is a lack of knowledge of applications of mostly theoretical circular economy strategies and corresponding key technologies for wind turbines to ensure efficient material recovery of used components. With regard to the identified research needs, our work contributes to the investigation of the reuse potential of steel derived from the towers of wind energy plants. Especially emphasizing its role as a secondary material within the circular economy paradigm. From a manufacturing perspective, our research focuses on evaluating the feasibility of bending pipe segments into a plane shape. To this end, the press-bending process is being investigated with the aid of FE simulations. The investigations are focused on examining the achievable flatness of the workpiece and analysing the effective process forces, which can be used to derive requirements for the machine tools. The study provides the foundation for the production-related realisation of the bending of tubular tower segments to a plane shape. Building on this, the remaining service life of the material can be investigated experimentally in future studies.