The return of investment analysis of a PHEV charging station with coordinated charging

Plug-in Hybrid Electric Vehicles (PHEVs) are becoming increasingly popular all over the world. Therefore, some associated public infrastructures will have to be established, such as smart parking zones, charging stations, and charging piles, etc. This paper only focuses on the smart charging station. A comprehensive analysis upon the impacts of electricity price on the return of investment (ROI) of the charging station with a coordinating charging is presented. First, a coordinated charging and discharging model is presented which considers the profits of all three partners, namely the utility, the charging station and the customers. Second, the bidirectional money flow model of the station with both utility and customer are presented as well. Third, the hierarchical optimization model is introduced to solve the Mixed Integer Linear Programming problems. Fourth, a simulation based on a real database of a typical city is run and the Bass' diffusion model is applied to forecast the amount of PHEVs arriving at the charging station per day. Lastly, it is proved that an optimal coordinating charging strategy will reduce the years of ROI significantly and a figure presenting the relationship between price and ROI years is given.