Presentations

Abstract

The increasing deployment of wind farms in complex terrain highlights the limitations of conventional preconstruction site suitability methodologies when applied to heterogeneous wind conditions. While IEC 61400-1 standards provide a solid and widely adopted framework, their generic assumptions regarding turbulence, directional resolution and combined wind effects may be insufficient to properly characterize structural risk, which impacts directly in energy potential, in sites dominated by strong directional or seasonal variability, elevated turbulence intensity and complex flow phenomena. This can result in either underestimated loads or overly conservative operational constraints, both of which negatively affect project outcomes. This paper presents an advanced preconstructive assessment methodology aimed at obtaining comprehensive wind direction and seasonal loads analysis to evaluate structural risk, that reduces uncertainty and can lead to optimize energy production in complex onshore wind farm sites as will help to reduce Wind Sector Management (WSM) strategies. The approach integrates high-resolution wind resource characterization with detailed aeroelastic load simulations, enabling a risk-based evaluation of site suitability prior to construction. The methodology is demonstrated through its application to several wind farms located in complex terrain, using exclusively wind data and wind conditions analyzed at the preconstruction stage. The proposed framework extends beyond minimum IEC requirements by resolving site-specific wind conditions into several wind directions per turbine position and taking into account seasonal effects (day and night included) if large differences are forecasted. Wind inputs include directional and seasonal Weibull distributions, turbulence intensity, wind shear, inflow angle and air density. Although not strictly required by applicable standards, this level of directional and seasonal granularity is shown to be critical for capturing the dominant drivers of fatigue damage accumulation and extreme loading in complex environments. Validated aeroelastic models are used to perform fatigue, extreme load and tip-to-tower clearance analyses under site-specific boundary conditions and realistic operational assumptions. Loads obtained from the simulations are systematically compared against design certification limits, allowing the identification of specific wind speed and direction combinations that generate high structural risk. Based on this quantitative assessment, a targeted Wind Sector Management strategy is defined, restricting operation only in those conditions where overloads are detected, rather than applying broad or generic curtailments. The results demonstrate that the integration of detailed wind resource assessment and preconstructive loads analysis leads to a significant reduction in uncertainty and improved decision-making at early project stages. The optimized sector-based strategy effectively mitigates structural risk while preserving energy production in benign wind conditions. Compared to non-directional and no seasonal or conservative approaches, the methodology achieves higher annual energy production while extending the expected lifetime of critical components such as blades, drivetrain and support structures. This work contributes to industry knowledge by demonstrating how advanced, data-driven preconstructive methodologies can bridge the gap between wind resource assessment and structural integrity evaluation. The approach is fully compatible with existing IEC standards and provides a practical framework for developers and owners seeking to maximize energy yield while maintaining an acceptable risk profile in complex onshore and offshore wind farm developments.