Charging Profile Generation Tool for Grid Planning and Flexibility Assessment of EV Fleets

The transition in the transport sector towards battery-electric public transport (bus fleets) will present challenges to distribution system operator with regard to estimating and serving the demand peak with the present grid infrastructure. An understanding of the expected charging profile can provide knowledge about the peak load and its time of occurrence. This paper presents a generic mathematical formulation for a tool to generate the charging profile for battery-electric vehicle fleet operators, which uses information about the bus fleet’s characteristics to generate different scenarios concerning the charging demand profile, peak demand, and region of flexibility for the minimum and maximum number of chargers needed. The paper then uses city bus operator AtB in Trondheim, Norway as a real-life test case for this tool. Results show that the peak demand varies from 300 kW to 1050 kW, and the bus fleet operator can provide flexibility between 40% and 231% of their daily energy demand.