Local effects of wind turbines on near-surface wind speed in a desert steppe wind farm

This research describes and interprets spatial variation in near-surface wind speed around a large scale wind generation operation in a desert steppe environment of Inner Mongolia. Wind speeds were measured at five different heights and distances in front of and behind turbines and compared to that measured simultaneously from reference points immediately outside of the wind farm. The results showed that wind turbines clearly influence the spatial distribution of near-surface wind speed. Relative to reference points, near-surface wind velocity profiles measured at various distances from wind turbines followed a logarithmic distribution. The correlation coefficients for all points were above 0.95 except for a coefficient of 0.8278 corresponding to wind speeds measured 20 m in front of turbines. The wind speed increment rate at 20, 100, and 300 m in front of and behind turbines demonstrated the varying influence of turbines at different points. The area 100 m behind the turbine experienced maximum wind speeds at all height levels observed in the measurement area. The overall wind speed at 300 m distance was relatively low and variation nearest to the turbine was the most complex.