Stochastic Optimal Operation of a Multi carrier Energy System with Electric Vehicles and Combined Heat and Power Units

The paper presents a scheme to supply energy consumers by using a multicarrier energy system (MES). Each MES unit consists of electrical vehicles (EVs), and combined heat and power (CHP) units, which are called energy hubs (EHs) hereinafter. The objective function minimizes the cost of energy of the whole system while considering power flow equations in electricity, heat, and gas grids, where constraints include technical index limits of MESs, EVs, and CHPs. The model has been formed as a non-linear problem (NLP), in the following, the present study proposes a linear programming (LP) model as a substitute for equations of the NLP method so that the global optimal solution is found with a low computation error. Furthermore, the demand parameters, electricity price, and characteristics of EVs are uncertain. To model these uncertainties, we adopt the point estimate approach. The case study of this research considers electricity, gas, and heating grids simultaneously. The energy hubs relate all three grids to each other. The method is tested on a system through simulation using GAMS software. According to obtained numerical results, the suggested LP approach reaches an optimal point with reduced computation time and low error compared to the original formulations. As a result, the indices of different networks are improved using power management of the energy hubs.