A fleet does not fail because the vehicles are bad. It fails because a vehicle that should be working is parked.
The depot problem
Installing depot charging means a utility upgrade, trenching, permits, and a construction window measured in months. For a fleet leasing a yard, that may not even be allowed. Meanwhile the vehicles are already on the road.
What mobile charging changes
| Constraint | Depot charging | Mobile charging |
|---|---|---|
| Capital spend | High, upfront | Per visit or contract |
| Lead time | Months | Same week |
| Real estate | Dedicated bays | Existing parking |
| Scalability | Fixed | Add units as you add vehicles |
| Overnight top-up | Yes | Yes, on a scheduled route |
The three patterns that work
- Overnight top-up. A unit runs a fixed route through the yard, adding 25–50 miles per vehicle while the fleet sleeps.
- Mid-shift rescue. A driver returns early with a low pack; a unit meets the vehicle instead of the vehicle waiting for a bay.
- Return-to-service top-up. Vehicles come back from a shift at 30%; a scheduled visit gets them to a full start without a charger on site.
What it does not replace
A depot charger is still the cheapest per kWh for a large fleet with the space and the power. Mobile charging buys time until that exists, and covers the vehicles that do not fit the pattern.
How to measure it
Track vehicle-hours lost to charging before and after. Most fleets find the useful number is not the cost per visit but the trips recovered per week.