Depot charging across multiple shifts: set priorities when charging windows are tight

In a multi-shift operation, charging power should first go to the vehicle whose next operational task would otherwise be at risk. Earliest arrival or lowest battery level alone are not sufficient criteria. Combine the next departure, missing energy, technically achievable charging power and operational priority. Then continually check whether changes to routes have overtaken the plan.

Define readiness for the next task

A full battery is not always required. A vehicle assigned a short route may already be ready for duty, while another with a higher state of charge still needs energy for a longer assignment. Set a justified energy requirement and suitable reserve for each planned departure.

Readiness also includes the driver, loading, maintenance status and an accessible parking space. A vehicle that has technically finished charging is of no use if it is blocked behind another van or taken out of service for inspection. Dispatch should bring this information together rather than considering states of charge in isolation.

The general article on fleet charging strategy describes an appropriate charging mix. Multi-shift operation additionally requires decisions on the order in which scarce shared resources are used.

Calculate the remaining time buffer

A useful planning measure is the time until departure minus the estimated charging time still needed and the necessary handling tasks. The smaller this buffer, the more urgently the session needs review. A negative buffer shows that the target is no longer achievable under the assumed conditions.

Charging time is not a simple guarantee obtained by dividing energy by the maximum kW figure. Plan with a realistic average power over the relevant charging range. If this is unknown, test it in a pilot using the actual vehicles.

Also preserve this distinction: “not yet charged” does not automatically mean “urgent”. A vehicle with a long dwell time can wait in favour of an earlier departure, provided that this does not jeopardise its own deadline.

A hypothetical conflict illustrates prioritisation

Three compatible vehicles return at noon. They still need different amounts of energy from the charge point. This simplified example assumes constant available power; real charging curves and connection procedures must then be checked separately.

With 40 kW of shared available power, it would be inappropriate to assign all three vehicles the same fixed share from the outset. A needs 30 kW in the first hour. B can receive the remaining 10 kW. After A, B and C can continue to receive power, provided the equipment and vehicles support the planned allocation.

The example explains only the decision logic. It is not an installation proposal. If repositioning reduces A's hour to 45 minutes, the assumed 30 kW is no longer enough. You then need to change the power, departure, vehicle allocation or backup charging.

Set rules for simultaneous critical departures

If two vehicles can no longer charge in time at the same time, an algorithm cannot create extra capacity. Dispatch needs a previously agreed order: which route has a binding time, which can be postponed and which other vehicle can take over?

Avoid hidden decisions created by an arbitrary order in the system. A high priority should have an operational justification and an owner. Otherwise, the same users always receive precedence until the overall system is no longer transparent.

Ask a provider for specific demonstrations. Manufacturer Vector, for example, describes planning based on departure time and vehicle energy requirements. This demonstrates a function addressed by the market, but does not establish a corresponding integration with your dispatch system or identical implementation at StromNow. Vector: fleet and depot management.

Organise changes during the shift

A charging plan must be updated when vehicles return late, the next route becomes longer or a charge point fails. Define what information is available automatically and what the shift supervisor must enter. Any expected data integration should be checked during the project before it becomes an operational prerequisite.

Define when a deviation is escalated. A useful point is one at which a genuine alternative is still available. An alert five minutes before departure can be too late even if it is technically correct. Base the warning on the remaining charging and rescheduling time.

Also document when data is considered outdated. A battery level last reported hours ago should not become the basis of a binding departure forecast without being flagged. When data is missing, operations need an agreed conservative fallback process.

Use shift handover as a checkpoint

The handover should answer a few specific questions: which vehicles are ready, which are still charging and which departures are at risk? Who takes over unresolved faults? Which vehicles have been swapped? What special rules apply to the next period?

Create an overview with the vehicle reference, next task, target time and outstanding energy requirement. A long list of historical charging sessions is less useful for this purpose. The person taking over the shift must be able to identify upcoming decisions.

Also check the physical sequence. Cables, parking positions and vehicle charging ports must fit the vehicle-movement plan. A theoretically free charge point is not a usable resource if reaching it requires extensive repositioning.

Optimise prices only within achievable charging plans

Low-cost electricity windows can be economically attractive. However, postpone charging only if the remaining windows still allow the agreed target, including reserve, to be met. A low price is no advantage if it subsequently requires an expensive, unplanned public charging stop.

Distinguish technical connection limits, any grid-side control and operational price optimisation. The plan must comply with all applicable conditions. It must not depend on another limit being exceptionally ignored at the crucial moment.

During the pilot, therefore, assess more than energy costs. Record on-time readiness, manual interventions, repositioning effort and replacement trips. A system that frequently needs help may be organisationally unsuitable despite good theoretical optimisation.

Test the process with real bottlenecks

Test a late return, a route extended at short notice and a failed charge point in a controlled scenario. Check that warnings, replanning and shift handover occur in time. The test group should include the operationally relevant vehicle types.

StromNow Logistics describes load management according to demand, dwell time and departure windows. For a consultation on a multi-shift depot, bring an actual shift plan, vehicle data and typical deviations. Agree specifically which prioritisation and data transfer your setup should support and how departure readiness will be demonstrated in the pilot.