The inequality between cold

heat and electric energy leads to great difficulties in accurate performance evaluation for cogeneration systems. Considering the fluctuation of heating steam temperature

chilled water temperature and ambient temperature during the actual operation of co-generation system of cold

heat and power(CCHP)

as well as the change characteristics of electricity price

heat price and cold price in different seasons

an evaluation model based on interval rough number analytic hierarchy process(AHP) is established

and the difference between different energies is measured by evaluating the energy weight. The obtained indexes not only consider the conversion between energy sources from a certain point of view

but also evaluate the results closer to the principle of energy cascade utilization

so that the performance of the CCHP system can be more comprehensively and completely described. Combining with the actual example of natural gas CCHP system

the weights and comprehensive utilization efficiency of several evaluation criteria are compared. Furthermore

the effect of cold and heat ratio and energy price changes on the system performance evaluation is also analyzed. The result shows that

compared with the previous methods

the comprehensive utilization efficiency calculated by this method can better reflect the actual performance of the system

which provides an effective means for accurate performance evaluation of the cogeneration system.