Document Type
Article
Author ORCID Identifier
Daniel Mortensen https://orcid.org/0000-0002-7649-4452
Greg Droge https://orcid.org/0000-0001-5247-8573
Justin Whitaker https://orcid.org/0000-0002-8552-5361
Journal/Book Title/Conference
World Electric Vehicle Journal
Volume
14
Issue
12
Publisher
MDPI AG
Publication Date
12-16-2023
First Page
1
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Last Page
27
Abstract
Recent attention for reduced carbon emissions has pushed transit authorities to adopt battery electric buses (BEBs). One challenge experienced by BEB users is extended charge times, which create logistical challenges and may force BEBs to charge when energy is more expensive. Furthermore, BEB charging leads to high power demands, which can significantly increase monthly power costs and may push the electrical infrastructure beyond its present capacity, requiring expensive upgrades. This work presents a novel method for minimizing the monthly cost of BEB charging while meeting bus route constraints. This method extends previous work by incorporating a more novel cost model, effects from uncontrolled loads, differences between daytime and overnight charging, and variable rate charging. A graph-based network-flow framework, represented by a mixed-integer linear program, encodes the charging action space, physical bus constraints, and battery state of the charge dynamics. The results for three scenarios are considered: uncontested charging, which uses equal numbers of buses and chargers; contested charging, which has more buses than chargers; and variable charge rates. Among other findings, we show that BEBs can be added to the fleet without raising the peak power demand for only the cost of the energy, suggesting that conversion to electrified transit is possible without upgrading power delivery infrastructure.
Recommended Citation
Mortensen, D.; Gunther, J.; Droge, G.; Whitaker, J. Cost Minimization for Charging Electric Bus Fleets. World Electr. Veh. J. 2023, 14, 351. https://doi.org/10.3390/wevj14120351