Design of a sustainable rotor blade for wind turbines

Abstract

At the Institute of Lightweight Systems of the German Aerospace Center, research in the field of the further development of wind turbines is also being conducted. One research topic is the development of sustainable rotor blades. The constructive approach of facilitated material separation in later recycling processes in combination with a material replacement of the conventional materials is pursued here. Therefore, different material combinations based on wood veneer materials or natural fibre composites were first analysed with the NREL-preliminary design tool WISDEM and then optimised with the DLR-optimisation framework lightworks. In this thesis, the state of the art about rotor blades in wind turbines, concepts for a sustainable design of these and the rotor blade design process are first discussed. Then the definition of the investigated use cases and the reference turbine is described. Furthermore, the preliminary and the advanced optimisation procedures are documented. Finally, the generated rotor blades are analysed with respect to the trade-off between sustainability and performance. This shows, that the design concepts based on birch LVL with a recycled foam core and on flax fibre in combination with a balsa wood core are the most balanced concepts with regard to the parameters blade mass, Levelised Cost of Energy (LCoE) and Global Warming Potential (GWP).