Reborn and upgrading: Optimum repowering planning for offshore wind farms

Abstract

Since the first offshore wind farm (OWF) was raised, with a total installed capacity of 32.4 GW by the end of 2020, the offshore wind power industry has experienced rapid development in the past two decades. In the next years, the decommissioning of OWFs needs to be paid attention in the countries where the offshore wind power is developed much early. In order to tap the residual value of decommissioned OWFs and reduce the damage to the ocean environment, this paper focuses on the repowering planning of OWFs, and proposes a repowering strategy considering the health conditions of wind turbines (WTs). Firstly, an evaluation method based on dynamic degradation is proposed, considering the influence of marine meteorological factors and the interaction between components on the health conditions of offshore WTs. An optimum decommissioning scheme is formulated according to the evaluation results. Aiming at the optimal levelized cost of energy (LCOE), the repowering strategy of a decommissioned OWF is optimized. Based on the case study of a real OWF in China, the results show that the repowering strategy proposed in this paper effectively reduces the LCOE and improves the repowering efficiency of the OWF, which can provide reference for the future decommissioning of OWFs.

Keywords

• Offshore wind farm
• Repowering
• Health condition evaluation
• Optimal planning