With pantograph charging, nobody connects anything: charging starts when the bus parks under the pantograph. With cable charging, depot staff connect the parked buses in one round. A smartbus (ordinary bus + SmartDEPOT™) drives itself inside the depot, without a driver: to its assigned charger, and between chargers at night.
Why the cable is the question
At night, buses come back, park and wait for power. Someone has to bring each bus to its charger: today that is the driver at the end of the shift, or a shunter during the night. Across assessed depots, manual depot movement takes 10 to over 35 minutes per vehicle per day, depending on depot layout, fleet size and shift organisation. At MZA Warsaw, the measured figure is about 35 minutes a day for each bus: parking, charging approach, washing and repositioning; it varies with depot layout and fleet. Every depot move the smartbus makes returns driver time to line service.
Pantograph: the connection is part of parking
With a pantograph, the smartbus drives itself to its assigned charging position, and charging starts when it parks there. When the charging plan says so, the bus moves on to the next charging position or to its departure lane, so one charging place can serve more than one bus a night. Jorge Salazar, Project Manager at Diggia, describes such a depot in The State of Smart Depots 2026: there, “the boundary between vehicle movement and charging management disappears”.
Cable: staff connect the parked buses in one round
With plug-in chargers, a person still connects the cable. The smartbus changes how that work is organised: buses park themselves at their charging positions in the order the depot management system sets, and depot staff connect the parked buses in one round, without driving any bus.
Who plans the charging night
The plan comes from the depot management system (DMS). The DMS plans where each bus parks, when it charges and when it goes to the wash or the workshop, and sends a drive order: a vehicle ID and a target position. SmartDEPOT™ Mission Control supervises the movements, and the smartbus reports its position in real time. Dave Van Meerbeeck, CEO & Founder of Treelight, names the condition in the same report: “the system knows at 23:00 which bus needs to leave at 05:20 fully charged”.
A supervisor in the control room releases the movements in SmartDEPOT™ Mission Control and steps in when a bus stops and asks for a decision. Inside the depot, the bus drives empty at low speed on a known layout. If anything is unclear, it stops.
More on the depot as a system: Depot of the future. How smartbuses fit more buses on a site with chargers: How many parking places does a bus depot lose to chargers? Where this stands today, with who is on board where: Where does depot autonomy for city buses stand in 2026?
Questions operators ask
No. The driver hands over the bus at the depot entrance. Inside the depot, the smartbus drives itself to its assigned charging position, and between charging positions at night, at low speed and under supervision in SmartDEPOT™ Mission Control.
Yes. With a pantograph, charging starts when the bus parks at its charging position, so no one is needed at the bay.
Depot staff. The buses park themselves at their charging positions in the planned order, and staff connect the parked buses in one round, without driving any bus.
Yes, when buses change charging positions during the night. A smartbus moves on when the charging plan says so and lines up for the first departures in the morning.
The depot management system (DMS). It plans where each bus parks and when it charges, and sends drive orders to SmartDEPOT™ Mission Control. The smartbus reports its position in real time.
Operators who want their own numbers start with Depot Minutes, a free online tool for depot time estimates, and the Smartbus Onboard Program, a site survey and data exercise in their own depot.
Smartbuses in every depot.