Study on the Resilience of the Integrated Energy System

Integrated energy system (IES) is the composite infrastructure system with subsystems such as electricity, natural gas, heat/cooling, etc. IES can improve efficiency, reduce pollution emission, and lower the dependence of economy on fossil fuels. IES is directly and physically connected to corresponding energy consumers, therefore it is an essential national infrastructure. With the increasing awareness of the threats from rare events such as extreme natural disasters or man-made attacks to the energy system, the study on energy resilience draws more attention. Still at the starting stage, existing studies on energy resilience is carried out mostly on individual energy system regardless of their interdependence. In the paper, the objective is to investigate the resilience of the IES. Firstly the IES and the interdependence among its subsystems are thoroughly analyzed. Then energy resilience as a concept is systematically discussed, and existing studies, including resilience evaluation methods, are compared and evaluated. Real life experiences of energy systems battling extreme events in enhancing resilience are summarized as well. With the integration of renewable energy and distributed energy resources (DERs), the IES is being reshaped and its resilience face more challenges, which will be investigated in detail. Finally future research trends about IES resilience evaluation, improvement and new technology are presented.