Optimizing the Location of On-Route Fast-Charging Stations in a Battery Electric Bus System

The transportation system is responsible for producing approximately 18% of total gas emissions in Australia. Electrified public transport, mainly in the form of Battery electric buses (BEBs), stands at the intersection of mobility and electricity systems and is a promising alternative for conventional bus fleets in achieving zero-emission targets. To provide reliable mobility service using BEBs, different charging methods, including battery swapping, fast and normal charging in depots, and main or on-route bus stops, are required to merge charging requirements into the bus schedule. The mobility-desired fast charging could merge BEBs into the bus network with minimum effect on bus schedules; however, it may lead to unmanageable electricity demand. Therefore, a trade-off between mobility requirements and power system constraints should be achieved in the charging process. In this research, the optimal deployment of fast-charging stations for BEBs is addressed to minimize a cost function including the total cost of vehicle batteries, number of fast-charging stations, station electrification cost, and electricity demand. It is formulated as a constrained optimization problem and is solved using mixed-integer linear programming. Numerical simulations show the efficiency of the suggested approach when applied to a real-world bus network for the eastern suburbs of Melbourne, Victoria, Australia.