In order to effectively analyze ethylene plant's energy efficiency status

evaluate ethylene industry's energy level

and improve the energy efficiency

this paper proposes an energy efficiency evaluation method of index decomposition analysis based data envelopment analysis including slack variable in ethylene industry. In the proposed method

firstly

the IDA method is used to acquire the three energy performance indexes of the influencing energy consumption

i.e.

activity effect

structure effect

and intensity effect. Then by analyzing the three energy performance indexes

the DEA method based on slack variable is used to obtain a strategy for improving ethylene energy efficiency and production. Finally

the operation guidance can be applied to enhance the production efficiency of ethylene plants. The results verified the feasibility and effectiveness of the IDA-DEA evaluation method and the proposed IDA-DEA method provides a new idea for saving energy in the petrochemical industry.