The uptake of Electric Vehicles (EVs) is rapidly changing the landscape of urban mobility services. Transportation Network Companies (TNCs) have been following this trend by increasing the number of EVs in their fleets. Despite the amount of new charging infrastructure being installed in recent years in most major cities, there are not sufficiently many Charging Stations (CSs) to meet the massive demand. Recently, major TNCs have explored the prospect of establishing privately owned charging facilities that will enable faster and more economic charging. Given the scale and complexity of TNC operations, such decisions need to consider both the requirements of TNCs and local planning regulations.
To solve this problem, TSL has made an empirical study for the placement of charging stations dedicated to Electric Vehicles (EVs) from Transportation Network Companies (TNC) by distinguishing between on-street and off-street facilities and taking into account the restrictions set by local authorities with respect to the maximum number of on-street facilities per region.
The area of Chicago, Illinois, USA was used as a case study network. The nodes of the network were first clustered in order to derive the potential locations for the placement of charging stations. Next, an agent-based simulation model was implemented to identify the locations where the vehicles need recharging. An integer programming formulation was provided for the optimisation problem.
Due to the intractability of solving the proposed optimisation model optimally for realistic instances, TSL has implemented a genetic algorithm to solve it approximately and produce solutions for large problem instances. The algorithm was tested under fleet sizes ranging from 500 to 3500 vehicles.
Based on experimental results we calculated that approximately 25 million dollars will be needed to invest for the construction of 180 CSs, which are necessary to cover the charging demand of a TNC fleet of 3000 vehicles in the city of Chicago, assuming that the EVs constitute the 20% of the total number of vehicles. It was also found that when the penetration rate of EVs exceeds 30%, the number of opened CSs needs to increase by a rate of approximately 30%.