Adapting wind shear coefficients to urban morphology: Unlocking urban wind energy potential

Abstract

The varied roughness of building clusters makes the urban wind rather complex. The current exponential wind profile may not accurately capture the spatial variation of urban wind. This study aims to develop urban morphology-based exponents for the exponential wind profile model to improve the assessment of wind energy in urban areas. The Weather Research and Forecasting (WRF) model, combined with Local Climate Zones (LCZ), was used to simulate wind fields, validated with field data. The study then analyzed wind field distribution urban morphology, introducing wind shear coefficients adapted for various urban morphologies. The results were compared with the existing wind shear coefficients by assessing the wind power potential. The results indicated that wind shear coefficients increase from urban outskirts to centers, with minimal seasonal variation. The annual average wind shear coefficient peaked at 0.50 in Harbin and 0.49 in Guangzhou. Building density, height, and plot ratio (PR), significantly impacts wind fields. PR showed the strongest correlation with the wind shear coefficient as the determining factor. Wind shear coefficients for low (0.0–1.0), medium (1.0–2.0), and high PR zones (2.0+) were 0.33, 0.38, and 0.41 in Harbin, and 0.30,0.35, and 0.40 in Guangzhou, respectively, providing more accurate estimate of urban wind speed.