An assessment of circular economy measures in the construction value chain for offshore wind turbines

Sammanfattning: The construction sector is responsible for high energy consumption and large emissions of carbon dioxide, which is strongly linked to building materials. Within the European Union, the construction sector generates more than a third of all waste and circular economy is considered as a suitable approach to tackle these challenges. Furthermore, the need for renewable energy sources has increased, with wind turbines being an important source. However, there have long been difficulties in recycling the massive rotor blades from wind turbines, but recently the world's first recyclable rotor blades have been installed at an offshore wind farm in Germany which has been in operation since the end of 2022. With regard to this background, the purpose of the study has been to evaluate whether circular economy can be applied to offshore wind turbines. This has been assessed by making a case study of a wind developer who develops, builds, operates and decommissions wind farms and who, among other things, has developed the wind farm in Germany with recyclable rotor blades. Various circular measures within the construction value chain for offshore wind turbines applied by the developer have been evaluated. Data were collected through interviews and a document study. The result showed that circular economy can be applied to wind turbines to a certain extent. This conclusion is based on difficulties in completely excluding waste generation, for example large offshore foundations are planned to be left in the seabed after decommissioning wind farms. The study also showed that there are several challenges in the transition to a circular economy such as permitting processes, stakeholder involvement, financial obstacles and challenges associated with the rapid technical development of wind turbines. However, the study showed that the developer applies several circular measures within the framework of their operations, especially in maintenance.