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To achieve net-zero emissions, transit systems will eventually have to transition to fully electric buses. We introduce an integrated decision-making and energy modeling framework to analyze transition strategies from diesel to zero-emitting buses under various budget scenarios. Using a detailed energy model of the buses to predict fuel usage, we then optimally assign types of buses to scheduled trips to minimize diesel consumption and emissions. Applying this framework to the Pioneer Valley Transit Authority network, we find that under realistic budget and infrastructure constraints, an electrification future that allows a mix of electric and hybrid buses reduces emissions more effectively than an all-electric future. Specifically, for a fixed budget, incorporating hybrid buses results in an additional 6% emissions reduction over the 18-year planning horizon compared to an electric-only future. This shows that hybrid buses can speed up the elimination of diesel buses and maximize emissions reduction while mitigating infrastructure and financial constraints. Our framework evaluates different fleet transition futures and provides transit agencies with a data-driven framework to plan investments and meet their decarbonization targets under realistic budgetary and infrastructure constraints.
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E-transit-bench: simulation platform for analyzing electric public transit bus fleet operations
When electrified transit systems make grid aware choices, improved social welfare is achieved by scheduling charging at low grid impact locations and times causing reduced loss, minimal power quality issues and reduced grid stress. Electrifying transit fleet has numerous challenges like non availability of buses during charging, varying charging costs, etc., that are related the electric grid behavior. However, transit systems do not have access to the information about the co-evolution of the grid’s power flow and therefore cannot account for the power grid’s needs in its day to day operation. In this paper we propose a framework of transportation-grid co-simulation analyzing the spatio-temporal interaction between the transit operations with electric buses and the power distribution grid. Real-world data for a day’s traffic from Chattanooga city’s transit system is simulated in SUMO and integrated with a realistic distribution grid simulation (using GridLAB-D) to understand the grid impact due to the transit electrification. Charging information is obtained from the transportation simulation to feed into grid simulation to assess the impact of charging. We also discuss the impact to the grid with higher degree of Transit electrification that further necessitates such an integrated Transportation-Grid co-simulation to operate the integrated system optimally. Our future work includes extending the platform for optimizing the charging and trip assignment operations.
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- PAR ID:
- 10356662
- Date Published:
- Journal Name:
- Proceedings of the Thirteenth ACM International Conference on Future Energy Systems (e-Energy 2022)
- Page Range / eLocation ID:
- 532 to 541
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Conference Paper:
- https://doi.org/10.1145/3538637.3539586
