Mitigating the impact of fast charging on distribution grids using vehicle-to-vehicle power transfer: A Paris city case study

The deployment of DC fast charging stations (DCFCSs) in cities requires costly reinforcement of low-voltage (LV) distribution grids, due to the high power required. It results in high investments for the station operator as well as for the distribution system operator and limits the profitability of such projects. In this study, a novel concept of fast charging station which reduces the connection to the grid is presented. This station uses Vehicle-to-vehicle (V2V) power transfer from a fleet of carsharing electric vehicles to provide a high charging power while mitigating the power demand on the grid. Based on data from a carsharing operator in the city of Paris, a simulation model of a combined carsharing/V2V fast charging system is proposed, allowing to simulate carsharing trips and V2V transfers. The reduction of the grid connections required to provide fast charging is evaluated and the impact of the repeated discharges on the level of service of the carsharing system is discussed. Moreover, simulation of LV distribution grids allows to compare the grid losses of the V2V system with conventional DCFCSs.