Optimal charging of electric buses: a periodic discrete event approach

The use of electrical buses (EBs) is increasing all over the world to reduce pollution in cities. However, EBs' charging represents a high load and, to minimize costs, it is necessary to optimally manage the recharge according to the intrinsically periodic arrivals and departures of vehicles. Moreover, they can participate in demand response programs to help the distribution system operator to manage the electrical grid in emergencies. In this paper, we propose a new model and a periodic discrete event approach for the optimal charging of EBs. The considered optimization problem minimizes costs, the maximum power taken from the external grid, and the dissatisfaction related to demand response requests. The considered system is characterized by different vehicles that should be charged by the same charging station in a depot in which storage systems are present too. The developed model can be used either for the management of charging in a depot or to participate to demand response programs. The resulting optimization problem has been applied to a real case study in the Genoa Municipality in which a fleet of EBs is present.