EV Charging Technology

Last reviewed: 13 August 2026

A home EV charger install involves a sustained 32-amp electrical load, rules under BS 7671 Section 722, and - depending on your supply type - protection most people have never heard of before getting a quote. This is the electrical reality behind the price tag, in plain English.

Why installs advertised "from £500" often come in over £1,500

The advertised price rarely survives contact with a real property. The line items that push a quote up: a consumer unit (fuse box) upgrade if there's no spare capacity, a Henley block to tap off the main supply, cable runs of 15-30 metres or more requiring trenching across a driveway, and - for a lot of UK homes - extra earthing protection that a simple socket install would never need. None of that is padding; it's what a compliant install on an older or awkward property actually requires.

PME supplies, PEN faults, and why some chargers need an earth rod and others don't

Most modern UK homes are on a PME (Protective Multiple Earthing) supply, where the earth and neutral share a single conductor back to the network. Normally that's fine. The specific risk for EV charging is a PEN fault - a break in that shared conductor - which can make a charging car's metal body live relative to the ground it's parked on. Because of that risk, outdoor chargers on a PME supply need extra protection.

Historically that meant driving a physical earth rod into the ground to create an independent earth path - labour-intensive, and not something every garden or driveway makes easy. Newer smart chargers increasingly build the protection in instead: they monitor the supply and disconnect automatically if a PEN fault is detected, no rod required. A charger with that built in can genuinely be cheaper to install than one without, on the right property - which is the opposite of what the sticker price on the hardware suggests.

Notifying your DNO, and why you don't have to chase it yourself

Adding a 32-amp load to a property is exactly the kind of thing your electricity network operator (DNO) needs to know about, so they can check the local network has capacity. The paperwork for this is a standard part of a proper installation - your installer handles the notification, not you - but it's worth knowing it's happening, and being wary of anyone offering to skip it.

Why DIY installation is a firm no

Wiring a 32-amp charging circuit yourself to save on labour costs is not a grey area: it falls foul of Part P building regulations and BS 7671 Section 722, and it will invalidate standard home insurance. This isn't a "technically allowed but risky" situation - it's a straightforwardly bad idea, regardless of how confident you are with a screwdriver.

Checking the basics before you get a quote

One of the cheapest things you can do before calling an installer is check your own consumer unit for a spare way (an empty slot for a new circuit breaker) - it's a five-minute look that tells you upfront whether you're likely looking at a straightforward install or a fuse-board upgrade. Similarly, knowing the difference between an OZEV-approved installer and a standard electrician matters beyond paperwork - it's what makes you eligible for the grants covered in our grants guide in the first place.

Standards and product details in this category move fast - see oureditorial standards for how we keep articles current.