Wind power production is very predictable globally, to less extent locally – study

Onshore wind power production from the same capacity in one country can vary up to 25% from one year to another, however on a larger scale generation is much more stable, according to a study on the variability of wind power that combines data from the last 15 years.

Wind and solar resource assessment consultancy Eoltech has prepared the study by using the irec wind energy indexes. Published each month for 300 regions across 40 countries, they cover two thirds of wind farms in operation in the world.

Irec is a wind energy index that quantifies the production expected in a given period and compares it to the long-term average within each region.

According to Eoltech, its global yardstick encompasses over 400 GW in operating wind farms. It is more than 50% of the total power and more than 80% of the total number of known facilities.

Considering the global onshore wind power portfolio, annual production for the entire portfolio varies within a 3% range over the past 15 calendar years, the firm said.

The European portfolio index encompasses 185 GW in operating wind farms in 23 countries, which is over 88% of overall capacity. It covers more than 97% of individual wind farms.

According to the analysis, the annual production in Europe varies within a 7% range over the past 15 calendar years.

Eoltech CEO Habib Leseney said the production of an individual wind farm can differ significantly from one year to another, up to 25%, due to the local variation of the wind resource. But on a larger scale, like in Europe or the world, cumulative production is much more stable, he explained.

The analysis also demonstrated there is no downward trend in the global wind resource on a 15-year scale.

“Yes, the wind does always blow somewhere on the planet, and it is good news for wind power going forward,” Leseney added.