On Short-Term Variations of RES Power Generation and Associated Secondary Regulation Demand

Incorporating Renewable Energy Sources (RES) into power systems typically focuses on ensuring adequate energy production, but the variability in this production sometimes may get underestimated. Our research deals with 15-minute production data from RES available on the ENTSO-E Transparency platform, concentrating on Germany, Austria, and Hungary. Spanning nearly eight years of continuous data, our findings reveal that as more RES capacity is added, the marginal need for additional regulation reserve capacity per unit of new RES diminishes. This indicates that portfolio diversification statistically mitigates short-term variability to a significant, but limited extent.