Abstract: To enhance the operational flexibility of coal-fired power plants, a molten salt thermal energy storage system that utilizes electric heaters for heat storage and an additional steam turbine for heat release, including heat release schemes A (additional steam turbine exhaust entering the condenser) and B (additional steam turbine exhaust entering the deaerator), were designed. The thermodynamic performance of the integrated system was analyzed based on a 660 MW supercritical coal-fired power plant (CFPP) case study. Results show that in scheme B, the maximum net output power increment of the CFPP is 9.67% of the rated load, while in scheme A, the net output power increment of the CFPP is 11.04% of the rated load. Under the condition of maximum boiler feedwater split mass flow rate, the total energy efficiency of schemes A and B decreases from 43.61% to 43.05% and 42.81%, respectively, while their total energy efficiencies could increase from 42.83% to 44.90% and 44.47%, respectively. When boiler feedwater split mass flow rate is less than 60 kg/s, the equivalent round-trip efficiency of scheme B is higher than that of scheme A, with a maximum value of 48.47%.