In reheat and recompression cycle system

the high-pressure carbon dioxide fluid has high temperature at outlet of the high-temperature reheater

resulting in insufficient heat absorption of the working fluid entering the heat source heater. To solve this problem

the model of a supercritical carbon dioxide(S-CO_2) cycle photovoltaic coal complementary power generation system is established using Aspen Plus software. On the basis of the reheat-recompression cycle system

a novel dual-channel S-CO_2 cycle solar hybrid coal-fired power system is proposed. Moreover

the performance of the above two systems is analyzed and compared by applying the exergy analysis method. The results indicate that

the exergy efficiency of the new system can reach 40.578%

which is 3.494 percentage points higher than that of the reheat-recompression cycle system

and the exergy efficiency of the S-CO_2 cycle subsystem increases by 11.853 percentage points. The improvement of the exergy efficiency of the novel system can be attributed to the new path layout

which brings the third stage turbine to do work through full utilization of regenerative heat from the high temperature regenerator and reduces exergy losses from the main compressor and high temperature regenerator. Additionally

the contribution of solar energy in the new system is greater

resulting in an increase in output exergy from 9.846% to 10.059%.