Simulation-based planning and evaluation of depots for electric buses

Derzeit befinden sich Verkehrsbetriebe weltweit im Spannungsfeld zwischen der zügigen Einführung von emissionsfreien Stadtbussen zur Erreichung umwelt- und klimapolitischer Ziele, der Implementierung der dafür notwendigen, passenden Infrastruktur und der parallelen Umstellung von Betriebsprozessen. Bei dem aktuellen Roll-Out werden überwiegend batterieelektrische Stadtbusse vorgesehen. Mit deren zunehmendem Anteil konzentrieren sich die Herausforderungen auf die Gestaltung der Busdepots. Insbesondere bei Neuplanungen stellt sich die Frage der räumlichen Anordnung von Abstellplätzen und der erforderlichen Anlagen für den Fahrzeug-Service. Ladeinfrastruktur muss implementiert und eine ausreichende Stromversorgung sichergestellt werden. Hinzu kommt, dass unterschiedliche Ladestrategien existieren, die Auswirkungen auf den Energie- und Leistungsbedarf im Depot besitzen. Um diesen Bedarf zu decken ist der Ladevorgang in den Betriebsablauf so zu integrieren, dass weiterhin ein störungsfreier, effizienter Betrieb möglich ist. In der Literatur wurde die Planung von elektrischen Busdepots nur unzureichend untersucht. Daher ist das Ziel dieser Arbeit die Entwicklung einer Methodik zur Planung und Evaluation von elektrischen Busdepots, um Betreiber im Planungsprozess zu unterstützen und somit eine zügige Realisierung zu ermöglichen. Auf Basis einer Analyse von Busdepots und der Identifizierung relevanter Merkmale und Wirkungszusammenhänge, wurde ein diskretes, ereignisorientiertes Simulationsmodell entwickelt, um den dynamischen Depotbetrieb realitätsnah abzubilden. Wichtige Bestandteile des Modells sind Steuerungs- und Optimierungsalgorithmen für das Abstellen und Disponieren der Busse zur effizienten Nutzung der Abstellanlage, für das Lade- und Lastmanagement zur Auslegung des Netzanschlusses und für die Konfiguration der Abstellflächen. Das Modell kann durch den modularen Aufbau eine Vielzahl von Planungsszenarien abdecken. Die Anwendung der Methodik wird anhand eines realen Fallbeispiels zum Bau eines elektrischen Busdepots für den Betrieb von 39 Linien demonstriert. Das Ergebnis ist eine Planungsgrundlage bestehend aus einem Depotlayout, Fahrzeug-, Stellplatz- und Ladeinfrastrukturbedarf sowie Lastprofile zur Auslegung des Netzanschlusses. Weiterhin wird die Leistungsfähigkeit des elektrischen Depots durch quantitative Indikatoren bewertet.Transport operators worldwide are currently facing the challenge of a rapid introduction of zero-emission city buses to achieve environmental and climate policy goals, an implementation of the appropriate and necessary infrastructure, and a parallel conversion of operating processes. The current roll-out predominantly involves battery-electric city buses. With their increasing share, the challenges are concentrated on the design of the bus depots. The question of the spatial arrangement of parking spaces and the necessary facilities for vehicle servicing arises in particular in the case of new planning. Charging infrastructure must be implemented and a sufficient power supply must be ensured. In addition, different charging strategies exist, which have an impact on the energy and power demand in the depot. In order to meet this demand, the charging process must be integrated into the operational sequence in such a way to guarantee unobstructed, efficient operation. In the literature, the design of electric bus depots has been insufficiently investigated. Therefore, the aim of this thesis is to develop a methodology for the planning and evaluation of electric bus depots in order to support operators in the planning process and thus enable a rapid realization. Based on an analysis of bus depots and the identification of relevant characteristics and interdependencies, a discrete, event-oriented simulation model has been developed to realistically represent the dynamic depot operation. Important components of the model are control and optimization algorithms for parking and dispatching of buses to ensure efficient use of parking facilities, for charging and load management in order to design the grid connection and for the configuration of parking spaces. The model can cover a wide range of planning scenarios due to its modular design. The application of the methodology is demonstrated using a real case study for the construction of an electric bus depot for the operation of 39 lines. The result is a planning basis consisting of a depot layout, the demand for vehicles, parking spaces and charging infrastructure as well as load profiles for the design of the grid connection. Furthermore, the performance of the electric depot is evaluated by quantitative indicators

Review and Evaluation of Automated Charging Technologies for Heavy-Duty Vehicles

Automated charging technologies are becoming increasingly important in the electrification of heavy road freight transport, especially in combination with autonomous driving. This study provides a comprehensive analysis of automated charging technologies for electric heavy-duty vehicles (HDVs). It encompasses the entire spectrum of feasible technologies, including static and dynamic approaches, with each charging technology evaluated for its advantages, potentials, challenges and technology readiness level (TRL). Static conductive charging methods such as charging robots, underbody couplers, or pantographs show good potential, with pantographs being the most mature option. These technologies are progressing towards higher TRLs, with a focus on standardization and adaptability. While static wireless charging is operational for some prototype solutions, it encounters challenges related to implementation and efficiency. Dynamic conductive charging through an overhead contact line or contact rails holds promise for high-traffic HDV routes with the overhead contact line being the most developed option. Dynamic wireless charging, although facing efficiency challenges, offers the potential for seamless integration into roads and minimal wear and tear. Battery swapping is emerging as a practical solution to reduce downtime for charging, with varying levels of readiness across different implementations. To facilitate large-scale deployment, further standardization efforts are required. This study emphasizes the necessity for continued research and development to enhance efficiency, decrease costs and ensure seamless integration into existing infrastructures. Technologies that achieve this best will have the highest potential to significantly contribute to the creation of an efficiently automated and environmentally friendly transport sector

Implementation Schemes for Electric Bus Fleets at Depots with Optimized Energy Procurements in Virtual Power Plant Operations

For the purpose of utilizing electric bus fleets in metropolitan areas and with regard to providing active energy management at depots, a profound understanding of the transactions between the market entities involved in the charging process is given. The paper examines sophisticated charging strategies with energy procurements in joint market operation. Here, operation procedures and characteristics of a depot including the physical layout and utilization of appropriate charging infrastructure are investigated. A comprehensive model framework for a virtual power plant (VPP) is formulated and developed to integrate electric bus fleets in the power plant portfolio, enabling the provision of power system services. The proposed methodology is verified in numerical analysis by providing optimized dispatch schedules in day-ahead and intraday market operations