Evaluation of schemes for reservoir operation: from rule-curve to many-objective optimization

Quantitative comparison between different schemes of reservoir operation can provide valuable suggestions to decision-making and help to promote new planning tools under changing environment. A full spectrum of the schemes for reservoir operation range from rule-based setup (RBS), single-objective optimization setup (SOS), bi-objective optimization setup (BOS) to many-objective optimization setup (MOS) is considered. The Qinshitan Reservoir, a large reservoir in the southwest of China, is used as a case and the four schemes of reservoir operation are established with similar formulations and are evaluated quantitatively under typical hydrological years. For the considered optimization problem, progressive improvement on the solutions is obtained from RBS to SOS, then BOS and finally MOS. Amongst the models, the MOS provided a comprehensive perspective on reservoir operation and achieved the best performance for offering the most options to the decision making. The MOS also discovers a step-wise operational scheme that has not been captured by the RBS, the SOS and the BOS.