Presentations

Abstract

When a wind farm viability assessment indicates that curtailment is necessary to meet fatigue lifetime constraints, it could be financially advantageous to divide the turbine lifetime into two phases. The first phase operates at full power without curtailments, maximizing energy production and accelerating early cash flow to enhance financial viability. The second phase involves derated (curtailed) operation to ensure compliance with fatigue lifetime constraints. This study evaluates the financial implications extending the first period without curtailments and how this affects overall project viability of a highly constrained site. Seven curtailment strategies were evaluated on a densely spaced site with high wake interactions, each varying the number of initial full-power years before transitioning to derated operation. Energy yield scenarios were obtained from a fatigue-aware optimizer and translated into financial metrics including Net Present Value (NPV) and discounted payback time. A Monte Carlo simulation and Sobol sensitivity analysis were used to assess robustness on uncertain cost estimates and electricity price. The strategy without curtailment and with one year of full-power operation before curtailment were identified as optimal strategies solution across multiple financial test conditions, yielding the highest NPVs among the scenarios. Both achieved the most samples with break-even points within the design lifetime, with a mean payback time of 18 years. The results illustrate that curtailment, when applied strategically, can support turbine lifetime goals of highly constrained wind farms without necessarily reducing financial viability. In contrast, running turbines at full power for too long increases the risk of not reaching payback. These findings are particularly relevant as the industry shifts toward lifetime-aware asset management, and the presented method helps to evaluate the financial feasibility of wind farms that are in need of curtailment.