Study On The Reservoir Ecological-Power Optimal Operation And Its Ppplication

With relieving water resources maldistribution in time and space, reservoiroperation also changes the natural flow situation of the downstream channel, causingan adverse effect on ecological system of the downstream channel. As human societydevelops and water management thought changes, a growing number of scholarsargue that moderate compensation for ecological water of downstream channel shouldbe considered in reservoir operation. On the basis of evaluating alteration degree ofnatural flow situation induced by reservoir operation, the paper developed anecological-power optimal operation model with considering ecological factors inreservoir optimal operation and took Niululing Reservoir for example, to make thereservoir remain the original profiting function and reduce the negative impacts on theecological system of channel. The main research contents and results are as follows:(1) The influence on river ecosystem by reservoir operation was analyzed in fourareas of hydrological characteristics, physicochemical properties, river morphologyand coast ecology, and the necessity of this research was also verified.(2) Four methods of calculating the ecological water demands which are widelyused were reviewed, that is, hydrology method, hydraulic method, habitat ratingmethod and comprehensive method. A comparative analysis between applicationconditions and existing problems of each method was presented. In addition, takingNiululing Reservoir for example, the paper determined the minimum, the secondminimum and proper ecological water demands of its downstream channel byhydrology method, and rational evaluation of the results referring to Tennant was alsoexpressed.(3) To analyze the influence on river ecosystem by reservoir operation, the paperutilized five ecological significance hydrological parameters of flux, time, frequency,delay and change degree by the method of RVA, and took Niululing Reservoir forexample, to evaluate the change degree of natural flow induced by reservoir operation.These results indicate that a dramatical influence on river ecosystem by reservoiroperation occurs, especially after increasing the number of planned power station,which is against the ecological system. Therefore, ecological factors should be takeninto account in reservoir optimal operation, to reduce the negative impacts on theecological system.(4) An ecological-power optimal operation model was developed, in which theecological objectives and social objectives were translated into the constraintconditions of economic objectives. Accordingly, genetic algorithm program wasdeveloped to solve the model, and this paper took Niululing Reservoir as an exampleto research. An ecological-power optimal operation model for Niululing Reservoirsystem was developed, and four scheduling schemes were proposed based on thedetermined ecological water demands. By employing the model and genetic algorithm program, the impacts of river ecological water demands on power generation wereanalyzed in three typical years(water-rich, water-normal and water-shortage). Then,the benefits were compared to the contemporary operation results of the Reservoir,revealing that, this model can increase the generated energy distinctly taking accountof the river ecological water demands. The research provides both technical supportfor Niululing Reservoir operation and practical reference for similar studies.