Choosing a home EV charger

Home chargers differ far less in running cost than the marketing suggests, because running cost is set by your tariff rather than by the unit on the wall. Two features genuinely change what you pay. Everything else is convenience and styling.

Those two are scheduling and solar matching, and they are worth different amounts to different households, which is why “best charger” has no universal answer and does have a calculable one.

Scheduling is the one that saves money

Every worthwhile tariff for an electric car has a cheap window, such as Intelligent Octopus Go’s 8p rate against the capped 26.11p standard rate. Realising that saving requires the charge to happen inside the window, reliably, every night, and the worked tariff arithmetic puts the stake at £450 a year for a typical 8,000 mile household. The charger’s scheduling is the mechanism that either collects that or drops it.

There are three places scheduling can live, and they behave differently:

In the car. Set a departure time or a charging window in the vehicle. Works with any charger. The weakness is that some cars forget the schedule after a software update, or apply it inconsistently when plugged in at unusual times.

In the charger. Set the window in the charger’s app. Independent of the car, so it survives vehicle updates. This is generally the more reliable place, and brands such as Ohme built their reputation on deep tariff integration done here.

With the supplier. The tariff controls charging directly, which is how the cheapest smart tariffs work. Requires the car or charger to be on the supported list, which is a compatibility check to run before switching tariff, not after.

Whichever you choose, use one of them and not two. Two schedules that disagree is the most common reason a car sits idle through the cheap window and then charges at 26.11p in the morning, which on a full 60kWh charge is the difference between about £5 and £16.

Solar matching is the one that uses your roof

If you have panels, this is the feature that makes charging from your own generation actually work. The myenergi zappi made the category famous, and most serious competitors now offer an equivalent mode.

A charger with solar matching modulates its draw to follow your surplus. When the array is producing two kilowatts more than the house is using, the car draws two kilowatts. When cloud passes, it backs off.

Without it, the charger draws its full rating, typically seven kilowatts, which is more than a domestic array produces. The difference is imported. The panels contribute, but the marketing image of a car running on sunshine is not what is happening.

One honest caveat before paying for the feature: whether solar matching earns anything depends on your tariff pair. On a flat tariff it captures the full 14p gap between import and export per unit. On a cheap overnight EV tariff with a 12p export rate, diverting surplus into the car can actually lose a few pence per unit against exporting and charging overnight. Buy the feature if your tariff rewards it, or if you expect to be on one that does.

Most chargers with the feature offer several modes: solar only, solar with a minimum top-up from the grid, and full-rate charging. The middle one is usually the useful setting. The trade-off is speed: solar-matched charging is slow and intermittent, suiting a car sitting on a drive all day, not one that needs eighty per cent by six o’clock.

What barely matters

Power rating. Almost all domestic units are around seven kilowatts, limited by a single-phase supply rather than by the charger. Higher ratings need a three-phase supply most homes do not have.

Cable versus socket. A tethered cable is more convenient; a socket lets you use different cables and looks tidier. Neither affects cost.

App polish. Pleasant, and irrelevant to the bill.

Installation questions worth asking

• Can my supply take it without an upgrade? An installer should check this, and the main fuse question is the survey item that decides the price.
• Is load balancing included, so the charger reduces its draw when the house is busy rather than tripping the main fuse?
• Does it need a permanent internet connection, and what happens when the connection drops? Some units refuse to start a smart session; better ones fall back to a stored schedule.
• Where will the isolator be?
• If you rent or own a flat, the EV chargepoint grant covers 75% up to £500; houses no longer qualify, so budget accordingly.

That connectivity question is worth pressing on. A charger that will not work offline is one bad router week away from charging at three times the rate you switched tariff for.

Choosing

For a household with no solar: pick on scheduling reliability and whether it is supported by the tariff you intend to use. The charger is the cheap component; the tariff integration is the product.

For a household with solar: solar matching is worth paying for when your tariff pair rewards it, and worth confirming the specific mode you want is included rather than an upsell.

Then check the tariff. That is where the money is, the difference between charger brands is tens of pounds a year at most while the tariff difference is hundreds, and the charger’s job is simply to make sure you actually land inside the cheap window, every night, without you thinking about it.