To improve the peak shaving capability of coal-fired power unit and the thermodynamic performance of energy storage system

this paper proposes a coal-fired peak shaving power generation system integrated with compressed air energy storage and gas turbine. In the proposed system

the compressed air from the energy storage subsystem is combusted with the fuel for expansion. Then

the expanded air is introduced into the ultra-supercritical 1 000 MW coal-fired boiler for further utilization. The results indicate that the integrated system can achieve zero output power generation from the coal-fired unit with an external load consumption capability of 25.29 MW

while the maximum output power generation can increase by 506.43 MW

improving peak-shaving depth by 83.17%. At the same time

the equivalent round-trip efficiency of the energy storage system is 80.71%. Exergy analysis reveals that

compared to the reference compressed air energy storage system

exergy destructions in the process of compressed air potential energy and thermal energy during energy release operation are reduced by 35.90 MW and 39.00 MW

respectively. Meanwhile

there is an increase in exergy destruction of 11.05 MW during the air compression process in the energy storage operation. By optimizing the inlet temperature of the second-stage air compressor

the equivalent round-trip efficiency of the energy storage system can be further improved by 2.96 percentage points

achieving an optimal value of 83.67%. The integrated system provides a new idea for deep peak shaving of coal-fired power plants

while the compressed air energy storage efficiency can also be significantly improved.