Analyzing and Forecasting Lightning Flashes and the Related Wind Gusts at a Wind Energy Power Plant in a Hilly Region of Western Greece

Abstract

Wind energy power plants are vulnerable, among others, to abrupt weather changes caused especially by thunderstorms associated with lightning activity and the accompanying severe wind gusts and rapid wind direction changes. Due to a range of damages such phenomena may cause, the knowledge of the relationship between the storm systems and the produced wind field is essential to establish a wind power plant during the construction and operation phase as well. In first part of this study, the relationship of severe wind gusts in regard to lightning activity in a wind farm in a hilly region of western Greece is investigated. Wind data come from wind turbines covering a period of three years (2012-2014), while the corresponding lightning data from the ZEUS lighting detection network. The analysis shows that wind gusts are well correlated to lightning strikes. Furthermore, correlation maximizes during winter when well organized weather systems affect the area and minimum in summer as a result of local storms due to thermal instability. In the second part the study focuses on the development of an ANN model in order to forecast these two parameters in a horizon of 1-h ahead by using except for the wind data, four variables namely CAPE, TTI, wind speed at the 500 hPa isobaric level and the 0-6 km vertical wind shear. The results revealed that proposed model could be considered as a promising tool in simulating the occurrence both of wind gusts and lightning flashes providing a relatively good evidence of the possibility of occurrence of such events.