Analysis of vertical wind shear in the Southern Great Plains and potential impacts on estimation of wind energy production

This paper describes the analysis of near-surface wind speeds in Western Oklahoma. The goals of this research are to characterise the nocturnal low-level jet (LLJ) in the region, and to assess the impact wind variability, vertical shear and the LLJ on wind energy calculations. Results show the seasonal variability in wind characteristics as well as in the vertical wind shear, and also illustrate the errors associated with traditional estimates of wind power density in locations with a decoupled wind field. A comparison of projected energy output from three standard commercial turbines shows that traditional density estimations significantly underestimated power yield. The mean wind power density estimated via traditional means is significantly less than a more complete determination incorporating the LLJ. This difference illustrates the need to acquire accurate information regarding 50-150 m wind variability to produce improved estimates of wind energy resources.

Keywords: wind energy calculations, wind power density, wind climatology, nocturnal low-level jet, energy resource assessment, vertical wind shear, wind speeds, USA, United States, wind variability, wind turbines, wind energy resources