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Quantifying the Hurricane Risk to Offshore Wind Turbines

Stephen Rose, Paulina Jaramillo, Jay Apt, Mitch Small, Iris Grossmann

Carnegie Mellon University

May 21st, 2012

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U.S. Has Good OffshoreWind Resources

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Wind Turbines are Vulnerable to Hurricanes

Typhoon Maemi, Okinawa, 2003

Takahara, et al (2004)

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We Fit a GEV Distribution to Hurricane Intensity

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We Model Probability of Tower Buckling by a Log-Logistic Function

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We Model Distribution of Turbines Destroyed in 20 Years

• No replacement: Phase-Type distribution• Replacement: compound Poisson

distribution

Assumptions:- Single wind farm- Each turbine experiences same conditions

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Turbines Designed to Survive Category 1 Hurricane

50-turbine wind farm

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Turbines Destroyed in 20 Years50-turbine wind farm

Not yawingYawing

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Turbines Destroyed in 20 Years50-turbine wind farm

Not yawingYawing

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Turbines Destroyed in 20 Years50-turbine wind farm

Not yawingYawing

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Turbines Destroyed in 20 Years50-turbine wind farm

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High-Category Hurricanes Cause Most Expected Damage

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Engineering Changes Can Reduce Risk

• Backup power for yaw system– Survival depends on active system– Wind vane must survive– Turbine must yaw quickly

• Stronger towers and blades– More steel in tower– More fiberglass in blades– 20 – 30% cost increase

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Careful Siting Can Reduce Risk

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Future Research: How Much Reserve Power is Needed?

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Quantifying the Hurricane Risk to Offshore Wind Turbines

Stephen Rose, Paulina Jaramillo, Jay Apt, Mitch Small, Iris Grossmann

Carnegie Mellon University

May 21st, 2012