The ecological optimization dispatch of the Three Gorges reservoir considering aquatic organism protection

This paper focus on the ecological optimization operation problem of the Three Gorges reservoir in flood recession. In this season, the primary goal of the reservoir is impounding to get the maximum economic benefit. As people increasing concern about their environment, impact of the reservoir operation to the aquatic habitat at the downstream area becomes an increasing important factor. The conflict between economic benefit and habitat conservation makes the dispatch a multi-objective problem. In this paper, stored energy at the end of dispatch period is proposed to be the economic objective and the weighted usable area (WUA) of the habitat is used to represent the environmental demand. The multi-objective differential evolution (MODE) and a particular constraint handling strategy proposed in this paper are used to solve this problem. Simulation results show that the proposed constraint handling strategy improves the performance of MODE in solving this problem. More importantly, the Pareto optimal front of different operating condition shows that the conflict between economic benefit and environmental benefit is sharp, especially in low flow years. The degree of conflict relates to the value of average inflow. So it is necessary to consider the habitat conservation while operating. And this work provides a support to aquatic organism protection and ecological operation of the Three Gorges reservoir.