Optimal Design of Integrated Energy System Considering Economics, Autonomy and Carbon Emissions

Energy management and suitable sizing are regarded as major concerns at the time of designing integrated energy systems. Finding an efficient framework that combines sustainable design, reliable operation and lifetime cost at minimal level is essential for society, customers and investors. In this regard, a novel multi-objective optimization model for the design of integrated energy system with electric, thermal and cooling subsystem is established to simultaneously minimize the economic, technical and environmental objectives. It aims to obtain the optimal sizing of each component such as photovoltaic panels, wind turbine, battery energy storage system, combined cooling, heating and power generation system, heat storage tank, gas boiler and electric chiller considering system performance in economics, system autonomy and carbon emissions. A hybrid energy system in residential area is taken as a case study to demonstrate the application of the proposed method, the Pareto front of the multi-objective problem is obtained via NSGA-II method, and four design plans on the Pareto front selected by Topsis method are analyzed and discussed. Such analysis show that the optimum solution could effectively reduce both the economic and environmental impacts of the integrated energy system as well as improve the system autonomy towards main grid. And the comparison about the results illustrated the reliability of the optimization model in this paper. This study demonstrates the high capability of the proposed design optimization in supporting economic design, improving autonomic operation and reducing the carbon emissions, meanwhile meeting multiple loads.