在火用分析及火用经济分析的基础上，说明了排弃火用与待回收火用的关系，就不同的回收情况，系统地研究了能量系统中排弃火用的计价问题；指出对于能量的逐级回收利用，传统的按物流的序贯分析计价方法并不适用于排弃火用的计价，基于能量系统双子系统模型，提出了当量计价的概念以解决排弃火用的计价问题。最后以催化裂化烟气能量回收方案的演变过程及排弃火用计价的变化表明了此计价方法的实际应用情况。 On the basis of exergy analysis and exergy economic analysis, the relationship between the exergy and the exergy to be recovered is described. The pricing problem of exergy exergy in the energy system is systematically studied for different recovery situations. The gradual recovery and utilization of energy, the traditional method of sequential analysis by logistics is not suitable for the pricing of abandoned exergy. Based on the two-subsystem model of energy system, the concept of equivalence pricing is proposed to solve the problem of exergy pricing . Finally, the evolution of energy recovery scheme of flue gas and the change of abandoned exergy pricing show the practical application of this pricing method.