High Wind Shear and Ramp Events within the Rotor Layer across the Iowa Tall Tower Network

Unexpected changes in wind speed and high wind shear events create significant uncertainty in power production and potential damage to wind turbine components. Improved understanding of the behavior of wind within the rotor layer is imperative for increasing efficiency in wind power production. High wind shear events create stress on wind turbine blades which can lead to shortened life spans. We report wind shear events reaching 8 ms^-1 across an 80-m rotor layer, or a shear exponent of 0.738, at a network of five meteorological towers across Iowa. We examined the ability of the WRF model to reproduce these events and identify opportunities for improving short-term forecasts as well as better characterizing the wind resource. Analysis of network wind speeds at 50 m, 100 m, 150 m, and 200 m reveal conditions for synchronous and sequential ramp events across multiple wind farms. Our goal is to develop improved forecasting schemes and better characterize conditions of high damage potential for turbines.