Increasing extreme winds challenge offshore wind energy resilience

Area of Science:

• Climate Science
• Renewable Energy Engineering
• Oceanography

Background:

• Offshore wind energy systems face increasing threats from climate change-amplified extreme winds.
• Turbine resilience is determined by the fifty-year return period wind speed (U50), a critical design parameter.
• Long-term trends and spatial variability of oceanic U50 remain largely unexamined.

Purpose of the Study:

• To investigate global long-term trends and spatial variability of oceanic fifty-year return period wind speeds (U50).
• To assess the impact of changing wind extremes on existing and planned offshore wind farms.
• To highlight the need for adaptive offshore wind energy infrastructure.

Main Methods:

• Utilized hourly ERA5 wind speed data from 1940 to 2023 at 100 meters above sea level.
• Analyzed long-term trends and spatial patterns of U50 across global oceans.
• Correlated U50 trends with offshore wind farm locations and cyclone activity.

Main Results:

• Observed a significant global increase in oceanic U50 at 0.016 m s⁻¹ yr⁻¹ (p < 0.01).
• Identified upward U50 trends in 62.85% of coastal regions.
• Found over 40% of Asian and European offshore wind farms have exceeded Class III turbine design thresholds (37.5 m s⁻¹), with many in regions of increasing U50 trends linked to cyclone activity.

Conclusions:

• Oceanic fifty-year return period wind speeds (U50) are increasing globally due to climate change.
• A substantial portion of offshore wind farms are vulnerable to current and future wind extremes.
• Urgent adaptation of offshore wind energy infrastructure is required to address evolving wind conditions.