Assessment of Offshore Wind Energy Potential and Turbine Performance in Sri Lanka

Abstract

This study assesses the offshore wind energy potential in three selected coastal sites around Sri Lanka through an evaluation of wind resources, turbine performance, and site-specific characteristics. Annual mean wind speeds were obtained from the Global Wind Atlas at various heights and extrapolated to turbine hub heights using the power law wind profile. Five reference turbine types ranging from 4 MW to 7 MW were analysed based on their power curves and hub heights. Results indicate that large rotor, low specific-power turbines, typically with rotor diameters of 200 m or more, achieve the highest capacity factors of around 54-60 % across all sites. Bathymetric analysis showed that in Area 2, around 75% of the area has a water depth less than 50 m, underscoring the suitability of monopile foundations for a starting project. Furthermore, the evaluated turbines demonstrated sufficient structural resilience under extreme wind conditions, with 3-second gust wind speeds around 70 m/s, ranking IEC Class 1 turbines suitable for storms around Sri Lanka’s coastline. Overall, the results highlight the strong potential for offshore wind development in Sri Lanka, particularly through the development of medium-to-large rotor turbines and floating foundation technologies in deeper offshore zones.