Getting your grid connection: the operator's guide to the DNO

Grid capacity is where most depot electrification projects either get moving or get stuck. Before you buy a single charger, the question that decides your timeline is a simple one: is there enough power at your site, and if not, how long and how much to get it? This guide walks through the process an operator actually faces with their Distribution Network Operator (DNO) — without the jargon.

Why the grid comes first

It’s tempting to start with vehicles and chargers, because that’s the visible part of the project. But the electricity supply is the constraint that everything else depends on. A depot that needs to charge a fleet overnight can easily require several times the power it draws today, and the DNO connection to deliver that power is frequently the longest lead-time item in the whole project — commonly six to twelve months, and sometimes considerably more where network reinforcement is needed.

Engaging early is the single most valuable thing you can do. The estimator linked at the end of this guide gives you a first read on your likely peak demand so you can start that conversation from an informed position.

kVA vs kW, and why your DNO talks in kVA

Chargers are rated in kilowatts (kW) — the useful power delivered to the vehicle. Your grid connection, though, is measured in kilovolt-amperes (kVA), which accounts for how efficiently that power is drawn (the power factor). For planning purposes the two are close, but not identical, and your DNO will frame your available and requested capacity in kVA. When you size a site, you add up the simultaneous charger load, apply a sensible diversity factor (not every charger runs flat out at once), and compare that against your existing connection capacity.

The connection conversation

Your first step is to find out your current agreed supply capacity, then estimate your future peak. If the future peak fits inside your existing capacity, you may need no reinforcement at all — the best possible outcome. If it doesn’t, the DNO will scope what’s needed, from a straightforward upgrade to more substantial network reinforcement, each with its own cost and timeline. Smart charging and on-site battery storage can materially reduce the peak you need to request, sometimes avoiding reinforcement entirely — which is exactly why they belong in the conversation early rather than as an afterthought.

What to do next

Get a first estimate of your peak demand, find your current supply capacity, and open a dialogue with your DNO before you commit to a charger specification. Being able to say “here’s roughly what we’ll need and when” turns a cold enquiry into a productive planning conversation — and keeps the grid from becoming the thing that holds your whole project up.