The optimal structure planning and energy management strategies of smart multi energy systems

Multi energy system is considered an effective pattern to improve the energy efficiency and reduce energy supply cost by integrating multi energy carriers. Face abundance energy convertor and storage devices with various characteristics, how to select the types and capacities of devices, how to connect and manage the selected devices are core challenging problems to design the optimal structures of new multi energy systems. A generic optimal planning framework and model is proposed to design multi energy systems, which can obtain both the optimal structure configuration and energy management strategies. The optimal planning problem is formulated as a mixed-integer linear programming model with the objective to minimize the overall cost. Three different energy system schemes are compared to demonstrate the effectiveness and advantages of the proposed optimal planning model. Simulation results show that the multi energy system designed by the proposed planning model (scheme 3) shows better economic and environmental performances than the conventional centralized energy system (scheme 1) and the typical combined cooling, heating and power systems (scheme 2). Compared with scheme 1, the total annual and carbon emission costs of scheme 3 decrease by 35.21% and 55.34%, respectively. While, compared to scheme 2, the total annual and carbon emission costs of scheme 3 decrease by 14.53% and 26.14%, respectively. Moreover, the robustness and performances of the optimization planning model are demonstrated through sensitivity and comparative analyses.