Optimal Operation of Energy Hubs in an Integrated Energy Network Considering Multiple Energy Carriers

Energy hubs play an important role in implementing the integrated energy system as an interconnection point between various energy components and networks. Energy networks also influence the management of the energy hubs. Therefore, the problem of optimal operation of the energy hubs and energy networks is modeled as a bi-level optimization problem in this paper. In the proposed bi-level model, the objective of the upper level problem is to minimize the operation cost of the energy hubs, and the objective of the lower level problem is to minimize the cost of the energy networks. The amount of energy consumed by the energy hubs and the marginal electricity price are considered as the interaction variables between the higher level and the lower level. In addition, the optimal operation cost of the energy hubs associated with power grid and natural gas network is optimized using group search optimizer (GSO). Moreover, the methodology is applied to a 4-hub test system which is utilized to demonstrate the applicability of the presented methodology.