To enhance the utilization efficiency of exhaust heat from gas turbines

a novel gas-coal combined cycle is proposed for efficient power generation. In this new integrated power generation system

the high temperature exhaust from the gas turbine is coupled with the air preheater of the supercritical coal-fired plant to drive the main supercritical steam cycle for efficient power generation. Subsequently

the mid- and low-temperature exhaust is coupled with the feedwater regeneration unit of the coal-fired plant

saving a portion of steam bleeding to increase the power generation of the steam turbine. This paper compares and analyzes the thermodynamic performance and economic feasibility of this novel efficient combined power generation system with reference systems. The research results indicate that the thermal-to-power conversion efficiency of the gas turbine exhaust is improved by 2.76%

and the net output power increases by 10.44 MW

owing to the integration with a high-parameter supercritical steam cycle; compared with the conventional gas turbine combined cycle

the net power generation efficiency has increased by 1.49%. The levelized cost of electricity is 60.34 ＄/(MW·h)

reduced by 1.02%

due to the decreased total investment cost and the improved net electric power output. In addition

compared to other feedwater heating concepts

the proposed integrated system generates an additional 17.60 MW of electric power and reduces the levelized cost of electricity by 1.23 ＄/(MW·h)

demonstrating advantages in both energy efficiency and economics. In conclusion

this paper provides a new approach for efficient utilization of exhaust heat from gas turbine through incorporating gas turbine and coal-fired power plants

with practical significance in engineering.