Under the strategic goal of “carbon peaking and carbon neutrality”

the penetration rate of new energy sources is increasing

and coal power is gradually transforming into a flexibly adjustable power supply. While the flexible operation of coal-fired generating units will lead to energy efficiency losses and additional pollutant emissions

which have a certain degree of impact on the cost of power generation and are not conducive to the further exploitation of coal power flexibility resources. In this paper

a method for grading the flexible operating performance of coal-fired units is constructed. By calculating the performance indicators to assess the flexibility performance of coal-fired units under specific operating conditions

the relationship between the unit coal consumption rate and the generation of some air pollutants that affect the cost of power generation and the operational flexibility is investigated. Meanwhile

the kilowatt-hour cost of coal-fired power plants at the second level is estimated. Finally

second-scale operating data collected from a 330 MW unit are used to evaluate the impact of coal-fired unit flexibility on the cost of electricity generation

and build least squares support vector machine(LSSVM) model to realize the prediction of unit power cost under different flexibility levels. The research results indicate that prediction error in specific conditions can be reduced by 50% compared with that in full conditions.