From 2008 to 2023, Eoltech conducted an extensive study, analyzing over 400 GW of operational wind farms around the world. This substantial sample represents more than half of the global installed capacity for onshore wind power and includes over 80% of all onshore wind farms internationally. The study’s European focus examined 185 GW of operational wind farms, accounting for more than 88% of the continent’s installed wind power capacity and covering over 97% of its wind farms. Researchers used the IREC Index for this study, a specialized wind energy index that compares expected production on a given period to the long-term average within each region.
Key findings
- The annual wind energy index for the global onshore wind power portfolio varied within a remarkably narrow range of ±3% over the past 15 years, indicating very stable wind resource availability on a global scale from year to year.
- Localized fluctuations in annual production could be as high as ±25%, primarily due to geographical and meteorological variations.
- In Europe, annual indices showed slightly higher fluctuations within a ±7% range over the same 15-year period. This increased variability could be attributed to Europe’s diverse climatic and topographical conditions.
Implications for investors and operators
The predictability of wind energy on a global scale offers significant reassurance for investors and operators. The IREC Index, as used by Eoltech in its analysis, provides an essential tool for asset managers and wind farm owners to monitor and manage their portfolios effectively. By understanding both the global stability and local variability of wind resources, stakeholders can optimize their operational strategies and investment decisions.