VTT is your partner of choice in planning and design of urban electric bus systems as well as electrification of other commercial vehicles and mobile machinery. We support you in all key areas of the process:
- Electric bus technologies and analysis
- Charging infrastructure design
- Traction battery dimensioning and system energy management
- City planning, electrification strategies and roll-out
- Complete system design, techno-economic (TCO) optimisation
- Support in procurement processes
- Electrification in mining, logistics, port operations, marine vessels
Electric buses suit well for public city transportation, where the driving is predefined as the route length, timetable, daily mileage and operation time. The overall energy efficiency of an electric vehicle consists of the efficiencies of the powertrain components used. In addition to optimising the individual subsystems of the vehicle, the whole system should be studied to find the most suitable components for improvement. In this, finding the optimal control strategy is important. When inspecting a whole fleet of electric buses, the charging system and the bus routes need to be also considered to ensure optimal fleet and energy management.
Planning of electric bus systems
Using our in-house built design tool, VTT Smart eFleet, it is possible to study the prospects for electrifying the public transportation in a given city. The tool uses basic bus line data together with geographical information of the route to generate a driving cycle to represent the desired bus lines. The energy consumption on a given route is calculated using our electric vehicle simulation model.
It is possible to study optimal locations for charging stations and strategies for charging. Dimensioning the capacity and power for the battery and for the charging stations is possible. In addition, effect of the charging strategy on the battery lifetime can be predicted.
Scalability and roll-out strategies for electric can be analysed with the geographic design tool as well. This includes selection of bus lines to be electrified, scalability of the charging infrastructure for cost-optimal system design.
With the aid of our total cost of ownership (TCO) model, the total costs incurring from owning and operating fleets of different electric buses in comparison with conventional diesel buses can be calculated. Different scenarios and systemic arrangements can be reviewed with the well parametrised model together with the vehicle and bus system models. Sensitivity analyses reveal dependencies on parameters such as daily mileage (utilisation rate), battery type, price and lifetime. This supports in finding optimal solutions for electrification.
Bus fleet operation is modelled using a map-based approach to make it possible inspect the system in
An example of a TCO analysis on operation of electric city buses in comparison with conventional
diesel buses, including both capital and operational costs. Dependency on daily mileage (utilisation
rate) illustrated as a critical parameter. (Note: results not generally applicable)
Watch the video: The Future of Finland - Electric transport
by Professor Howie Jacobs