Abstract: Accuracy of the model is one of the key points affecting the operation schemes of the regional integrated energy system (RIES). The efficiencies of energy conversion devices are usually assumed to be constant in the energy hub (EH) model, which may result in unreasonable operation schemes for the RIES. An operation optimization method for RIES that considers part-load performances of the devices is proposed in this paper. Firstly, a dynamic EH (DEH) model is developed for determining the time-varying efficiencies of energy conversion devices. A DEH-based operation optimization method for RIES is then proposed. Finally, the proposed method is applied to a typical RIES. Results demonstrate that the model, by considering the part-load performances of devices, can improve the accuracy and the practicality of the RIES operation scheme.