Cooperative Operation Optimization Of Coal-fired Power Plants Under Carbon Emission Constraints

To help achieve the goal of "double carbon",China is planning to build the new type of power supply system with new energy as the main source.China’s coal-fired power supply structure determines that when the penetration rate of new energy is increasing,the flexible regulation capability of coal power needs to be tapped to enhance system flexibility.However,coal-fired power plants have a significant increase in coal consumption per kWh during deep peaking,and the characteristics of coal consumption per kWh with load changes vary significantly among different types of coal-fired power plants.With the development of power market and the continuous promotion of "double carbon" target,how coal-fired power producers can achieve the optimal allocation of power resources by participating in the power market has become an urgent issue to be solved.First,the paper reviews the research available on the operation of coal-fired power plants in the electricity and ancillary services markets.Second,the operating costs of coal-fired units at different peaking stages were analyzed considering the differences in technical characteristics,and a two-stage model of cooperative operation optimization for coal-fired power plants based on economic objectives was established.Third,considering the carbon emission reduction target constraint,a two-stage model of cooperative operation optimization of power plants based on environmental objectives is further developed.Finally,the overall benefits of the coal-fired power plant system in different deep peaking scenarios are calculated and analyzed as the penetration of renewable energy increases.Firstly,this paper analyzes the operating costs of different coal-fired power plants at different peaking stages considering the differences in their technical characteristics,and based on this,a two-stage model of cooperative operation optimization of coal-fired power producers based on economic objectives is established.Secondly,considering the carbon emission reduction target constraint,a two-stage model of cooperative operation optimization of power producers based on environmental objectives is further established.Finally,the overall benefits of coal-fired power producers are analyzed considering different renewable energy penetration rates and different peaking depths.The results show that deep peaking of coal-fired power plants can reduce the overall carbon emissions and increase the renewable energy consumption rate,but there are differences in the total system benefits of coal-fired power plants with different deep peaking schemes.The optimization of coal-fired power producers based on environmental objectives can effectively reduce the overall carbon emissions and ensure the full consumption of renewable energy,but the total revenue of coal-fired power producers will be reduced.Optimization based on environmental objectives can better exploit the technical advantages of large-capacity power plants,when the large-capacity power plants operate at high load and the small-capacity power plants perform deep peaking to provide flexibility to the system.As the penetration of renewable energy increases,the overall economy of coal-fired generators operating together based on environmental objectives begins to emerge.Therefore,in the future,with a higher share of renewable energy,coal-fired power producers can better achieve the overall low carbon economy of the system when operating together based on environmental objectives.