Optimal Multiobjective Scheduling of Hydropower Stations in Day-Ahead Electricity Market: Considering Ecological Benefits

Abstract

At present, most research on the optimal scheduling of hydropower stations in the day-ahead electricity market focuses on the optimal power generation benefit, which does not consider the ecological impact of the generated discharge flow on downstream rivers. To address this situation, the ecological impact of electricity markets on rivers downstream of annually regulated hydropower stations is studied, and adjustment methods for traditional scheduling methods are proposed to achieve better ecological benefits. To this end, a multitimescale nested forecasting scheduling model is proposed for simulating hydropower station scheduling. In addition, the ecological flow index of the distribution flow method, an easy-to-implement ecological indicator model, was used to quantify the ecological benefits of discharge flows. A hydropower station on the upper course of the Lancang River in China was used to analyze the electricity market’s impact on downstream river ecology. The results show that under the optimal power generation benefit scheme, the ecological benefits are influenced not only by electricity price characteristics but also by multitimescale nested scheduling. Based on an analysis of these two factors, the general rules for the ecological benefits of rivers downstream of annually regulated hydropower stations in the day-ahead electricity market are summarized. In addition, the relationship between power generation and ecological benefits is analyzed for various schemes in a multiobjective scheduling problem framework. Finally, adjustment methods for traditional scheduling methods are proposed to achieve better ecological benefits.