Characterizing coastal wind energy resources based on sodar and microwave radiometer observations

Wind energy is a mature and cost-effective solution to greenhouse gas emission reduction and climate change mitigation. Wind resource assessment is the most pivotal activity before wind farm development since it determines the bankability of the wind project. Based on the joint use of a Doppler wind sodar (sonic detection and ranging) system and a microwave radiometer, this paper investigates the wind and thermal characteristics and wind energy resources in a coastal region of Hong Kong. First, wind climatology and variability, as well as their correlation with large-scale and local meteorological and geographical conditions, are analyzed and discussed. Then, statistical distributions of wind speed are evaluated, and the goodness-of-fit of the Weibull, Kappa, Wakeby, Normal-Weibull mixture, and Weibull-Weibull mixture distributions is assessed. Subsequently, the probability distribution and variation of atmospheric stability are examined, and their effects on vertical wind shear, wind profile, and wind speed at turbine hub height are revealed. Lastly, the spatiotemporal variation of wind power density is investigated with attention paid to air density. The results presented in this paper are expected to offer insights into coastal wind and thermal characteristics, provide references for vertical extrapolation of wind speed and wind turbine load evaluation, and facilitate wind farm development in coastal regions.