The MENDEL project was launched in January 2016: it set out to show how smart charging networks, combined with information and communications technology, could allow large electric bus fleets to be run reliably and economically.
The project was led by INIT, with input from research and commercial partners, and was funded by the German government.
In the Smart Grid subproject, for example, the partners developed software solutions to enable smart planning and control of the e-bus power grid. A program was developed to determine the optimal charging infrastructure for opportunity charging (charging en route) in a bus network by analysing infrastructure data from the electricity provider and schedule information.
Another program builds on this to optimise vehicle routes and schedule charges. The allotted charging time can be adapted ad-hoc where required, extending or shortening charging breaks according to network load.
Another subproject, called ITS, looked at reducing variable operating costs. The project showed that significant savings can be made by reducing energy-intensive starting procedures, so a central public transport prioritisation system has been developed to take into account charge levels and planned charging times.
This is connected to a traffic management system run by the local authority: if a bus reaches a critical charge state, it can be routed as quickly as possible with traffic signal priority, for example. The on-board computer also provides the driver with real-time information on the distance to the next traffic light and predicts when the lights will next turn green.