Wind Energy: A Turbulent, Intermittent Resource

Abstract

Statistics of high-frequency wind speed and power output measurements display turbulent fluctuations. Frequent wind gusts are observed through heavytailed statistics of increments of the wind velocity. These complex statistics cannot be reproduced using Gaussian wind field models, stressing the need for appropriate turbulence models. Wind fluctuations and wind gusts are converted by a wind energy converter (WEC) into electrical power fluctuations and power gusts fed into the grid. Similar heavy-tailed statistics are observed for the power output of a single WEC, a wind farm and to some extend to a large array of WECs. Furthermore, a stochastic approach is presented to model the conversion process operated by a WEC. Our results illustrate the impact of turbulence on wind power production, stressing the importance of turbulence research to properly integrate more and more wind energy into electrical networks.