Optimization of Reservoir Operation Considering both Hydropower Generation and Ecological Flow Requirement

摘要

There is a growing awareness to operate reservoirs with the consideration of downstream ecological needs. Nevertheless human benefits such as hydropower generation could be suffered a loss due to the additional competitor on river flow. This conflict normally presents a dilemma to water manager for the decision-making on operation policy, particular in the developing countries with power supply shortage. In order to balance the different interests, we took two cascaded reservoirs on China Yalongjiang River as a case and presented a trade-off method to identify the reservoir operational policies considering both hydropower generation and ecological flow requirements. Firstly, an optimization model of reservoir operation was advanced by using adaptive Genetic Algorithm. The objective function of the model was the annual hydropower generation. Instead of minimal ecological flow, the model took into account water flow representing the variational requirement of the local fish as a dynamic constraint. The constraint was allowed to be violated representing satisfaction degrees of the ecological flow requirement (SDEFR). The relationship between the SDEFR and the corresponding hydropower generation was then established. Based on this relation, the ecological-economical optimal reservoir operation was finally defined.