A Systematic Approach for Design and Analysis of Electrified Public Bus Transit Fleets

The wide integration of all battery electric buses (BEB) in the operation of public transit services is identified as one of the most promising means toward decarbonizing public transport systems. In response, public bus transit (PBT) and utility grid operators are currently in need of developing analytical techniques that enable them to conduct tradeoff analyses for the many available options of BEBs, charging infrastructure, and their associated system impacts. To that end, this article proposes a systematic and effective technique for feasibility check and configuration design of electrified PBT fleets without the need for the sophisticated optimization toolbox and high performance computing. The configuration design aims at determining the number of BEBs and their on-board battery capacities to meet the PBT prespecified schedule under different sizes of chargers. The proposed model is tailored for BEBs designed to either boost their batteries on-route at intermediate bus stations using fast chargers (opportunity charging) or charge while parked at the depot (in-depot charging). The developed model is also utilized to generate the aggregated power demand profiles of electrified PBT fleets under different charging practices. Based on the generated power demand profile, a lifecycle cost analysis is conducted to compare BEB-based PBT options to their diesel counterparts.