Towards electric bus system: planning, operating and evaluating
Doctoral thesis, 2023
The green transformation of public transportation is an indispensable way to achieve carbon neutrality. Governments and authorities are vigorously implementing electric bus procurement and charging infrastructure deployment programs. At this primary but urgent stage, how to reasonably plan the procurement of electric buses, how to arrange the operation of the heterogeneous fleet, and how to locate and scale the infrastructure are urgent issues to be solved. For a smooth transition to full electrification, this thesis aims to propose systematic guidance for the fleet and charging facilities, to ensure life-cycle efficiency and energy conservation from the planning to the operational phase.
One of the most important issues in the operational phase is the charge scheduling for electric buses, a new issue that is not present in the conventional transit system. How to take into account the charging location and time duration in bus scheduling and not cause additional load peaks to the grid is the first issue being addressed. A charging schedule optimization model is constructed for opportunity charging with battery wear and charging costs as optimization objectives. Besides, the uncertainty in energy consumption poses new challenges to daily operations. This thesis further specifies the daily charging schedules with the consideration of energy consumption uncertainty while safeguarding the punctuality of bus services.
In the context of e-mobility systems, battery sizing, charging station deployment, and bus scheduling emerge as crucial factors. Traditionally these elements have been approached and organized separately with battery sizing and charging facility deployment termed planning phase problems and bus scheduling belonging to operational phase issues. However, the integrated optimization of the three problems has advantages in terms of life-cycle costs and emissions. Therefore, a consolidated optimization model is proposed to collaboratively optimize the three problems and a life-cycle costs analysis framework is developed to examine the performance of the system from both economic and environmental aspects.
To improve the attractiveness and utilization of electric public transportation resources, two new solutions have been proposed in terms of charging strategy (vehicle-to-vehicle charging) and operational efficiency (mixed-flow transport). Vehicle-to-vehicle charging allows energy to be continuously transmitted along the road, reducing reliance on the accessibility and deployment of charging facilities. Mixed flow transport mode balances the directional travel demands and facilities the parcel delivery while ensuring the punctuality and safety of passenger transport.
One of the most important issues in the operational phase is the charge scheduling for electric buses, a new issue that is not present in the conventional transit system. How to take into account the charging location and time duration in bus scheduling and not cause additional load peaks to the grid is the first issue being addressed. A charging schedule optimization model is constructed for opportunity charging with battery wear and charging costs as optimization objectives. Besides, the uncertainty in energy consumption poses new challenges to daily operations. This thesis further specifies the daily charging schedules with the consideration of energy consumption uncertainty while safeguarding the punctuality of bus services.
In the context of e-mobility systems, battery sizing, charging station deployment, and bus scheduling emerge as crucial factors. Traditionally these elements have been approached and organized separately with battery sizing and charging facility deployment termed planning phase problems and bus scheduling belonging to operational phase issues. However, the integrated optimization of the three problems has advantages in terms of life-cycle costs and emissions. Therefore, a consolidated optimization model is proposed to collaboratively optimize the three problems and a life-cycle costs analysis framework is developed to examine the performance of the system from both economic and environmental aspects.
To improve the attractiveness and utilization of electric public transportation resources, two new solutions have been proposed in terms of charging strategy (vehicle-to-vehicle charging) and operational efficiency (mixed-flow transport). Vehicle-to-vehicle charging allows energy to be continuously transmitted along the road, reducing reliance on the accessibility and deployment of charging facilities. Mixed flow transport mode balances the directional travel demands and facilities the parcel delivery while ensuring the punctuality and safety of passenger transport.
charging station deployment
battery sizing
charge scheduling
bus electrification
bus scheduling
SB-H3, Sven Hultins Gata 6, Campus Johanneberg, Chalmers (zoom password: 951001)
Opponent: Ronghui Liu, Professor of Networks and Transport Operations, University of Leeds, UK
Author
Ziling Zeng
Chalmers, Architecture and Civil Engineering, Geology and Geotechnics
On the role of battery degradation in en-route charge scheduling for an electric bus system
Transportation Research Part E: Logistics and Transportation Review,;Vol. 161(2022)
Journal article
Zeng, Z., Wang, T., Qu, X., Optimizing en-route charging schedule for an electric bus network: Stochasticity and Real-world Practice.
Consolidating Bus Charger Deployment and Fleet Management for Public Transit Electrification: A Life-Cycle Cost Analysis Framework
Engineering,;Vol. In Press(2023)
Journal article
What's next for battery-electric bus charging systems
Communications in Transportation Research,;Vol. 3(2023)
Other text in scientific journal
Optimization of Electric Bus Scheduling for Mixed Passenger and Freight Flow in an Urban-Rural Transit System
IEEE Transactions on Intelligent Transportation Systems,;Vol. 24(2023)p. 1288-1298
Journal article
Imagine a future where public transportation is not just convenient, but also kinder to the environment. As governments push for carbon neutrality, electric buses are becoming the new norm. But making this shift isn't as simple as flipping a switch – it involves planning, operation, and maintenance that need smart solutions.
This thesis tackles urgent questions like how to plan electric bus fleets, manage their operations efficiently, and set up charging stations strategically. The goal? To make sure this transition is smooth and effective, reducing energy use and costs from start to finish.
One tricky puzzle it's solving is how to schedule the charging of electric buses. Unlike regular buses, these need recharging, and doing it right is crucial. This research creates charging schedules that avoid overloading the power grid, keep buses on time, and control battery aging.
But the innovation doesn't stop there. This research also explores exciting ideas like vehicle-to-vehicle charging, and finding ways to mix passenger and cargo transport. The life-cycle cost analysis framework serves as an overall evaluation method to assess the method provided.
With this research, the road to greener, smarter public transportation is getting clearer. It's turning challenges into opportunities and helping us all take a step towards a cleaner, better future.
This thesis tackles urgent questions like how to plan electric bus fleets, manage their operations efficiently, and set up charging stations strategically. The goal? To make sure this transition is smooth and effective, reducing energy use and costs from start to finish.
One tricky puzzle it's solving is how to schedule the charging of electric buses. Unlike regular buses, these need recharging, and doing it right is crucial. This research creates charging schedules that avoid overloading the power grid, keep buses on time, and control battery aging.
But the innovation doesn't stop there. This research also explores exciting ideas like vehicle-to-vehicle charging, and finding ways to mix passenger and cargo transport. The life-cycle cost analysis framework serves as an overall evaluation method to assess the method provided.
With this research, the road to greener, smarter public transportation is getting clearer. It's turning challenges into opportunities and helping us all take a step towards a cleaner, better future.
Areas of Advance
Transport
Subject Categories
Transport Systems and Logistics
Other Electrical Engineering, Electronic Engineering, Information Engineering
ISBN
978-91-7905-917-0
Doktorsavhandlingar vid Chalmers tekniska högskola. Ny serie: 5383
Publisher
Chalmers
SB-H3, Sven Hultins Gata 6, Campus Johanneberg, Chalmers (zoom password: 951001)
Opponent: Ronghui Liu, Professor of Networks and Transport Operations, University of Leeds, UK