With the growth of installed capacity of renewable energy power generation

coal-fired units need to undertake more peaking tasks. In order to improve the operational flexibility of coal-fired units

a 1 000 MW unit is taken as the research object

and six heat storage configurations and four heat release configurations of molten salt coupling are proposed based on the Ebsilon software

and the thermo-economic indexes of different heat storage and heat release coupling configurations are analyzed comparatively. The results show that

the peak shifting capacity of the system in the heat storage stage is positively correlated with the pressure loss of the heat transfer steam

and the thermal economy of heating the deaerator outlet feedwater in the heat release stage is the best. The heat storage of the electrically heated molten salt has the highest thermal and exergy efficiency

and configuration D-a has the strongest peak shifting capacity

with a peak shifting depth of up to 23.61%

but it has the largest coal consumption rate and exergy loss. Configuration F-d has the best thermal economy

with peak shifting depth

thermal efficiency

fuel efficiency and coal consumption rate of 23.42%

39.61%

38.40% and 310.2 g/(kW·h)

respectively.