Energy storage variation patterns and power optimization insights of Pubugou and Zipingpu reservoirs

(Objective) To formulate power optimization strategies based on energy storage scheduling and reveal the guiding role of cross-basin reservoir energy storage patterns in power production,(Methods) this study takes Pubugou and Zipingpu reservoirs as research objects. Utilizing dekadal water level data from 2021 to 2024, an energy storage calculation model was constructed to quantify key indicators such as energy storage ratio and drawdown rate. Systematic comparative analysis was conducted on inflow power characteristics, energy storage trends, and indicator differences between the two reservoirs.(Results) The results indicate: Pubugou exhibits a significantly higher inflow energy-to-flow ratio (4.9) compared to Zipingpu (3.4), indicating greater energy storage regulation potential (maximum variation range of energy storage ratio: 0.9737 vs. 0.9122). Abnormal drawdown phenomena during flood seasons at both reservoirs are closely associated with extreme climate events (e.g., the 2022 high-temperature drought), which triggered drastic inflow power fluctuations and multi-objective scheduling demands. The strong regulation capacity of Pubugou and the locational advantage of Zipingpu demonstrate significant complementarity.(Conclusion) A cross-basin collaborative scheduling framework and dynamic thresholds for energy storage ratio, developed based on these energy storage indicator differences, provide theoretical basis and decision-making support for optimizing wet-dry season power distribution, enhancing grid resilience, and achieving coordinated multi-objective scheduling (flood control-power generation-ecology).