Performance evaluation system for integrated multi-energy complementary systems adapted to the integration of new energy sources

To overcome the limitations of traditional hydropower operation evaluation indicators in characterizing integrated multi-energy complementary systems, this study develops a performance evaluation framework tailored to systems combining hydropower with wind and solar energy. Using the upper Yellow River clean energy base as a case study, a long-term operation model was constructed, and six schemes were designed under deterministic and stochastic optimization modes. A performance evaluation system was proposed, encompassing six key dimensions: energy efficiency, reliability, stability, resilience, robustness, and complementarity. This system was applied across three spatial levels: individual hydropower plants, hydro-wind-solar hybrid systems, and the entire basin-level integrated hydro-wind-solar system. The results indicate that the proposed evaluation system exhibits strong scientific rigor, systematic structure, and practical applicability, effectively distinguishing performance variations under different system configurations and operation modes. Under deterministic and stochastic optimization modes, the basin-scale integrated system achieved increases in annual average power generation of 1.3% and 0.6%, respectively, and demonstrated superior performance across multiple evaluation dimensions. These findings validate the scientific reliability of the proposed framework in assessing the operational effectiveness of integrated multi-energy complementary systems, offering a solid theoretical foundation and technical support for performance evaluation in complex renewable energy scenarios.