Electrification of commercial vehicle fleets

Developments in the fields of electric energy storage and power electronics are already enabling concepts for purely electrically powered city buses today, and they will continue to do so especially in the foreseeable future, which was considered unfeasible just a few years ago. Against this background, the Commercial Transport Working Group offers consulting services regarding the introduction of full-electric scheduled buses.

Based on extensive knowledge and experience in dealing with electric storage and drive technologies, an analysis of bus lines or line networks is carried out with regard to the possibilities of a step-by-step introduction of battery-powered electric buses. In addition, concepts for linear energy supply in the form of catenaries or inductive charging will be included in the considerations. If possible, a concept for the gradual introduction of electrically powered scheduled buses will be developed, covering a short- to medium-term scale.

The electrification of commercial vehicles brings a variety of challenges, especially in public transport. In order to be able to simulate these processes reliably, it is necessary to take into account the road-side energy supply both during halts and while on the move, as well as various recharging strategies and the high number of different auxiliary units. A high degree of positional accuracy is required for precise stopping at bus stops and recharging points.

Emission-free traffic zones impose additional constraints.

The Commercial Transport Working Group combines their members‘ accumulated experience in the field of public transport vehicle technology in a comprehensive simulation tool that describes entire vehicles in great detail. Precise submodels of the interaction of vehicles - environment - road, the powertrain, energy storage system, auxiliary units, air conditioning and heating, driver and passengers are combined to form a highly complex model that can be used, among others , to generate precise forecasts about the energy consumption of a specific vehicle and powertrain configuration under given operating conditions. The tool is supplemented by a system for obtaining relevant status information about the battery storage system, which is made available in a user-specific form via an interface or web interface.

Increasingly limited options for accessing inner cities are creating new challenges for commercial transport. The gradual tightening of entry restrictions, which includes environmental zones, already partially excludes diesel vehicles from entering inner city areas. Electromobility offers a good opportunity to provide adapted vehicles for urban delivery traffic. Due to the nature of the transport trips, the vehicles do not need long ranges. Therefore, current technology is already suitable for urban delivery transports. In cities, routes are short but fuel consumption and the wear of internal combustion engines is high. That is why electric trucks can demonstrate their strengths particularly well in dense urban traffic, displaying their   high potential for avoiding emissions, but also for saving fuel costs.

The Commercial Transport Working Group is investigating deployment scenarios and business models for electric trucks that make both the city air cleaner and delivery traffic more cost-effective.

The increasing share of electromobility and needs for ever higher charging capacities lead to challenges in the development of charging infrastructure - especially in the case of many electric vehicles being charged in one location (e. g., in parking garages, depots, logistics centers). Here, it is important to take into account user requirements for the charging infrastructure (e. g., arrival times, standing times, energy demand) while keeping an eye on the impact on the power grid. Simultaneous charging with high charging powers can lead to an overload of the grid connection point, which in turn requires expensive grid expansion measures. In addition to this complexity, electromobility is still a future topic for many infrastructure planners: the requirements of users and, above all, their numbers in the coming decades can so far only be estimated.

In order to evaluate the future charging demand and the corresponding necessary charging infrastructure (number of charging points, charging power, grid connection), simulation models are most often used. In these, scenarios for e-mobility market development are developed and first and thendriving behaviors and the resulting load flows at the charging infrastructure are mapped with the help of model calculations. In this way, different variants of infrastructure can be calculated and analyzed even before their construction begins. Additional grid-relief measures, such as load management, buffer batteries or local power generation, can also be taken into account and thus open up completely new possibilities for an integrated energy concept.

In order to provide sustainable supply and mobility solutions for the future, new resource-efficient and low-emission drive concepts for vehicles are indispensable. For the development and implementation of these drive concepts, it is of utmost interest to be able to predict their benefits, effectiveness, and efficiency quantitatively by simulation as early as possible, and to be able to make computer-aided comparisons of different variants. For this reason, Fraunhofer ITWM is engaged in the modeling and simulation of concrete application scenarios of vehicles with modern drive concepts, taking into account geography, traffic, vehicle configuration, and driving style, allowing the prediction of stress and energy demand specific to regions and use. The latter enables the efficient computer-aided analysis, evaluation and optimization of all these concepts, especially with regard to performance, range, CO2 emissions and energy efficiency. Not only does this significantly support vehicle engineering, but it also opens up the possibility of optimized fleet and infrastructure planning (e. g., of charging stations or hydrogen filling stations).

The Commercial Transport WG has many years of experience and expertise in the field of simulation, analysis and optimization at all levels of vehicle engineering, also including fleet and infrastructure design.