Abstract: In order to calculate exactly the allocation of carbon emission from power and heat supply of coal-fired unit,an allocation method based on exergy analysis is developed.For the coal-fired unit case,this method and the allocation method based on the ratio of heat-supply are used to calculate the carbon emission intensity of power generation,which are compared with the pure condensing condition.The results show that the change trend of carbon emission data of power generation for the calculations of the allocation method based on exergy analysis and the pure condensing condition is consistent with the load rate.The carbon emission intensity of power generation decreases with the increase of load rate.The allocation method based on exergy analysis can better reflect the real carbon emission characteristics of the unit.The allocation method based on heating ratio does not consider the grade of heat and allocates more carbon emissions to steam/heat supply,which results in the carbon emission intensity of power generation is obviously lower than that of pure condensation.These research results can provide reference for objectively evaluating the carbon emission intensity of power generation under steam/heat supply conditions of coal-fired unit,supporting low-carbon scheduling of coal power,and guiding the cascade utilization of energy.