Economic Benefit Analysis of Flexibility Improvement of Coal-Fired Power Plants

In recent years, the proportion of renewable energy in the power system has been increasing. Due to the intermittent nature of renewable energy, there is an increasing demand for peak shaving and frequency regulation in power systems, and there is an urgent need for coal-fired power plants(CFPPs) to undergo flexibility retrofits to improve their peak shaving capacity. This paper discusses the restrictive factors of operating flexibility of CFPPs and the key technologies of unit flexibility retrofits. The cost of flexibility retrofitting of CFPPs is analyzed, including the costs of unit modification, the opportunity costs and the life loss costs of unit participation in peak shaving. The benefits of participating in peak shaving for CFPPs under different peak shaving settlement modes are analyzed. Case studies show that when CFPPs participate in deep peak shaving, the proportion of opportunity cost is relatively large. When the unit is in a deep peak shaving state that requires combustion support, the combustion support cost accounts for a proportion of the deep peak shaving cost. The quantity of the peak shaving volume of units has a significant impact on the average cost of peak shaving, and it is necessary for the units operator to have an optimal balance between daily power generation and participating in peak shaving. It is suggested that the government provide technical and financial support for the flexibility retrofits for CFPPs. Meanwhile, it is suggested to channel the costs of flexibility retrofits of CFPPs through market mechanisms.