Storage energy variationrules and power optimization implications of Pubugou and Zipingpu Reservoirs

To formulate power optimization strategies based on storage energy scheduling and to reveal the guiding role to power production played by different reservoir storage energy rules, this study took the Pubugou and Zipingpu reservoirs as research objects.Based on ten-day water level data from 2021 to 2024, a storage energy calculation model was constructed to quantify key indicators such as the storage energy ratio and drawdown rate.The inflow power characteristics, storage energy variation trends, and indicator differences between the two reservoirs were systematically compared and analyzed.The results show that the wet-to-dry ratio of inflow power of Pubugou Reservoir (4.9) is significantly higher than that of Zipingpu Reservoir (3.4), indicating greater potential for storage energy regulation.The maximum variation ranges of the storage energy ratio are 0.973 7 and 0.912 2, respectively.Anomalous drawdown phenomena are observed in both reservoirs during flood seasons, which are closely related to drastic fluctuations in inflow power and multiple scheduling demands triggered by extreme climate events (e.g., the high-temperature drought in 2022).The strong regulation potential of Pubugou Reservoir and the locational advantages of Zipingpu Reservoir exhibit complementary characteristics.The coordinated scheduling framework and the dynamic thresholds for the storage energy ratio, developed based on differences in storage energy indicators, provide theoretical foundations and decision-making support for optimizing power allocation during wet and dry periods, enhancing grid resilience, and achieving multi-objective coordinated reservoir operation considering flood control, power generation, and ecological management.