Repowering of Legacy Wind Farms- A Techno-Economic Feasibility Case Study Based in Denmark

As global wind power installations age, the need for repowering has become important for enhancing efficiency and sustainably optimising the use of existing high-potential wind sites. This paper presents a techno-economic analysis of partial-repowering legacy wind farms, focusing on two wind farms: Farm A and Farm B in an Island in south Denmark. Conducted as an advisory research study using current wind farm data for commercial reasons the farm names are anonymised. The analysis evaluates two repowering scenarios for farms A and B through Case 1 (maintaining nameplate capacity) and Case 2 (higher capacity)- utilising an integrated model methodology connecting geotechnical assessments, energy production, and financial feasibility as its techno-economic assessment. Further sensitivity analysis on CAPEX (Capital expenditure), tendering price, and AEP (annual energy production) supports the robustness of Case 2, indicating its viability as a repowering approach for long-term sustainability. Overall, this study demonstrates that repowering with targeted techno-economic analysis can play a pivotal role in meeting renewable energy goals, particularly for aging wind installation infrastructure.