The greatest challenge for bus operators will be energy management for fleets of electric buses from different manufacturers. Cooperation from the manufacturers will be essential for efficient operations.
For decades it was sufficient to refuel diesel buses in the evening to ensure they could run their routes flawlessly the next day. With electric fleets, however, a new chapter begins. “Running two or three electric buses is no problem,” as one energy specialist put it. “Managing thirty or more electric buses is the biggest challenge yet for a bus company. Operators need to link energy management for charging their buses to route planning and operational data from buses already on the road.”
You can use your bus’s average battery consumption as the basis for drawing up a driving and charging schedule. Additional information from the previous day can be downloaded when the bus is being charged. “But that information is of no use, just like daily or weekly reporting,” the expert noted. “You need access throughout the day to operational data on each bus’s battery use. A bus may consume more or less than planned. Or it may return later than scheduled due to a flat tyre, an accident or traffic congestion. Such factors disrupt a pre-programmed charging plan and may result in buses not being sufficiently charged overnight to cope with the next day’s schedule.”
Redrawing charging schedules on the fly
For larger fleets, the underlying software must constantly redraw the schedule for all charging stations, sometimes also taking into account off-peak and peak rates from the energy supplier. Whereas until recently electric buses were typically charged once in full, the trend is now towards more staggered charging. On arrival at the charging station the bus is kept in standby with a limited charge, followed by almost full charging, then back to standby, with a top-up shortly before returning to service. While such a charging concept can be programmed, keeping it up to date requires real-time data from buses on the road.
And here lies the stumbling block for efficient energy management. Manufacturers build perfectly serviceable electric buses, offer extensive reporting tools, but are reluctant to provide real-time information on battery consumption during the day. For a fleet made up of buses from a single brand, a manufacturer may still be willing to make an exception.
A serious problem for mixed fleets
But for operators running vehicles from several different manufacturers, a serious problem arises. Each manufacturer has its own system of data collection and processing, and there is no compatibility whatsoever. In such cases, it is advisable to opt for an external software package (for example ChargePoint, which acquired ViriCity a few years ago) in which all data can be gathered and processed.
Energy and bus specialists therefore recommend that, when purchasing electric buses, operators should ask manufacturers directly about their willingness to provide data on battery use online and in real time, separate from their standard reporting. “Vehicles on the road must transmit that data to you so that an operator can process all information from any electric bus in a standardised way, enabling optimal charging schedules and efficient operation of your bus lines or network,” one bus specialist emphasised.