A second wind for turbine design

Wind turbines have a built-in cut-off mechanism to prevent damage during extreme winds. These towers are located along the Columbia River, on the border between Oregon and Washington in the United States.

© Oleg Moskaliuk/ Shutterstock.com

By splicing together two models describing normal and rare extreme conditions, KAUST researchers have developed a method to predict the frequency of winds strong enough to shut down wind turbines—even if such winds haven’t yet appeared in observations. The approach could help design and place wind farms in regions with more favorable wind energy resources.

Wind power is rapidly providing a significant proportion of the world’s energy mix and—when wind farms are located in windy areas—can provide relatively reliable power. The average power output of a wind farm at a given location is typically predicted using the average wind speed over time, and there are many mathematical models for this purpose.

However, wind turbines can be damaged when wind speeds exceed their engineered limit, causing them to shut down by turning or "feathering" the blades when the wind becomes too strong. Yet although wind farm outages due to high wind speeds could be a critical factor in the design and placement of wind farms for optimal power output, predicting the frequency and intensity of such events is far more challenging than the estimation of averages.

Daniela Castro-Camilo and KAUST colleagues in Raphaël Huser's group have now developed a method for predicting both average and extreme wind speeds, even if such high winds have never been measured.

“Our model is designed to provide forecasts beyond observed wind speeds,” says Castro-Camilo. “Our approach essentially corrects the extreme ‘tail’ in the data distribution, which is useful for obtaining better predictions for parameters like wind speed.”

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