Choosing the right charging hardware for your depot

“What charger do I need?” is usually the first question operators ask — and the honest answer is: probably not the one a salesperson would sell you. The right hardware follows from how your vehicles are actually used, not from the highest power rating on the page. Choose well and you spend less and draw less power; choose on horsepower alone and you pay twice — once for the charger, and again for the grid capacity to feed it. Here’s how to get it right.

Start with dwell time, not vehicle count

The single most useful number is dwell time — how long each vehicle sits parked and available to charge. A vehicle back at 5pm and out at 6am has a long window and needs only a modest charger to refill overnight. A vehicle on a tight turnaround needs a faster, pricier one. Working from real duty cycles usually reveals you need fewer, gentler chargers than a one-per-vehicle assumption suggests.

AC vs DC: the core choice

AC charging (typically up to 22 kW) uses cheaper hardware and is perfect for vehicles that sit for hours — which is most of a depot overnight. DC charging (50 kW to several hundred kW) is faster but the chargers cost far more and draw big peaks from your grid connection. The usual pattern is mostly AC for the overnight fleet, with a few DC chargers only where the timetable genuinely demands a quick top-up. Buying DC everywhere “to be safe” is the most common way to overspend.

Connectors and compatibility

You don’t really choose the plug — the vehicle does. In the UK and Europe, Type 2 covers AC and CCS covers DC rapid charging, and between them they fit almost every modern electric van, truck and bus. The very largest trucks are moving toward a new high-power standard, MCS, covered in the HGV depot guide. Match the connector and the power to your vehicles; there’s no benefit paying for 150 kW a vehicle can’t accept.

The one spec line that protects you

Whatever you buy, insist it is fully OCPP-compliant. OCPP is the open language that lets chargers work with different management software, so you can switch back-office systems or mix charger brands later instead of being locked to one supplier for a decade. It’s the cheapest insurance in the whole project — and the subject of the standards guide. Ask every supplier the question directly and get the answer in writing.

Tethered, untethered and split systems

A few practical choices remain. Tethered units have a fixed cable (convenient, quicker for drivers); untethered take any cable (flexible, tidier). On larger sites, split systems — a shared power cabinet feeding several dispensers — can be more cost-effective than standalone units and make load sharing easier. These are design details your installer will help with once the AC/DC and quantity decisions are made.

The bottom line

Good hardware choice is mostly about matching charger type and power to how long vehicles actually dwell, favouring AC for the overnight fleet, and refusing to over-buy on speed you can’t use. Nail the OCPP requirement so you stay free to change your mind. Use the Grid Capacity Estimator to see how your charger mix translates into grid demand before you commit to a specification.