"Should I get a 7kW or 22kW charger?" is one of the most common questions from new EV buyers. The marketing makes 22kW look like the obvious upgrade — three times faster! — but for the typical UK homeowner, a 22kW charger will run at exactly the same speed as a 7kW one. This guide explains why, and when 22kW genuinely is the right call.
Why single-phase vs three-phase matters
UK domestic electricity supply is almost always single-phase 230V at 100A. The maximum continuous load that supply can safely deliver to one device is around 7.4kW. That is why home wallboxes are sold as 7kW units — it is the practical ceiling.
Three-phase supplies deliver 230V across three separate phases, giving roughly three times the available power. Three-phase is standard in most commercial buildings, industrial estates and some rural homes (where the local DNO infrastructure happened to be installed that way). It is rare in suburban homes.
A 22kW charger needs all three phases to deliver 22kW. If you plug a 22kW charger into a single-phase supply, it will detect the lack of phases and throttle itself to 7.4kW — exactly the same as a 7kW unit.
Real-world charging speeds compared
| Charger rating | On single-phase | On three-phase | Range added per hour |
|---|---|---|---|
| 3.6 kW (granny lead from 13A socket) | 3.6 kW | 3.6 kW | ~12 miles/hr |
| 7 kW dedicated wallbox | 7 kW | 7 kW | ~28 miles/hr |
| 22 kW dedicated wallbox | 7.4 kW (throttled) | 22 kW | ~88 miles/hr (3-phase) |
| 50 kW DC rapid (public) | n/a | 50 kW | ~180 miles/hr |
For a typical UK driver covering 7,500 miles per year, an overnight 7kW charge of 8–10 hours adds 224–280 miles of range — far more than a single day's driving. A 22kW upgrade saves a few hours, but you are not driving overnight, so it usually saves nothing meaningful.
Does your car even accept 22kW?
Even on a three-phase supply with a 22kW charger, you only get 22kW if your car has an 11kW or 22kW on-board AC charger. Most don't.
| Vehicle | Max AC charge rate | Real charge rate on a 22kW unit |
|---|---|---|
| Tesla Model 3 Long Range | 11 kW | 11 kW |
| Tesla Model Y Long Range | 11 kW | 11 kW |
| Tesla Model S | 16.5 kW | 16.5 kW |
| VW ID.3 / ID.4 | 11 kW | 11 kW |
| Renault Zoe ZE50 R135 | 22 kW | 22 kW |
| Renault Megane E-Tech | 22 kW | 22 kW |
| Smart #1 / #3 | 22 kW | 22 kW |
| BMW i4 / i5 / iX (most variants) | 11 kW | 11 kW |
| Hyundai Ioniq 5 / Kia EV6 | 11 kW | 11 kW |
| Polestar 2 | 11 kW | 11 kW |
| Nissan Leaf (40 / 62 kWh) | 6.6 kW | 6.6 kW |
| MG4 / MG ZS EV | 7 kW (most trims) | 7 kW |
So even with three-phase + a 22kW charger, most cars max out at 11kW — adding around 44 miles of range per hour. Only a handful of cars (Renault Zoe, Megane E-Tech, Smart #1/#3, Audi e-tron GT) can use the full 22kW.
Hardware cost — 7kW vs 22kW
| 7 kW (residential) | 22 kW (commercial) | |
|---|---|---|
| Entry-level unit | £312 (Rolec WallPod) | £695 (Rolec EV Zura 22kW) |
| Mid-tier smart | £549 (Ohme Home Pro) | £1,099 (Easee One 22kW) |
| Premium smart | £999 (myenergi Zappi) | £1,299 (Zappi 22kW) |
Roughly speaking, 22kW units are 50–100% more expensive than the equivalent 7kW unit. Browse our full 7kW home charger collection or 22kW commercial charger collection.
Installation cost — including DNO upgrades
Hardware is only half the story. The bigger gap is in install costs.
| Scenario | Typical total install cost | Notes |
|---|---|---|
| 7kW on existing single-phase supply | £600 – £1,000 | Standard home install |
| 22kW on existing three-phase supply | £1,200 – £1,800 | Slightly more cabling / breakers |
| 22kW with new three-phase upgrade needed | £3,000 – £10,000+ | DNO upgrade + groundworks; 2–6 month lead time |
Upgrading a single-phase home to three-phase is a major job. Your DNO needs to dig up the road or driveway, replace the incoming cable and main fuse, and your electrician needs to install a new three-phase consumer unit. The cost varies wildly by region and existing infrastructure.
When 22kW makes sense
22kW chargers are not pointless — they are just a commercial product, not a residential one. They make sense in:
1. Business car parks
Workplaces have shorter dwell times (employees pop out for lunch, customers visit for an hour) so faster charging helps you serve more vehicles per socket. Three-phase supplies are also already in place at most commercial sites. See our guide to the best 22kW EV chargers for business car parks.
2. Fleet depots
Vans and pool vehicles need a faster turnaround between shifts. 22kW is often the right choice for last-mile fleets and council fleets.
3. Hotels, restaurants and public spaces
Customers who park for 1–2 hours benefit from 22kW because it adds enough range to make the visit worthwhile. 7kW would only add ~30 miles in that time.
4. Homes that already have three-phase
If you already have three-phase (some rural properties, converted barns, large detached homes) and you drive a Renault Zoe or Megane E-Tech, a 22kW unit at home is a sensible upgrade. The hardware costs more but the install is cheap, and your car will use the speed.
5. Multi-EV households planning ahead
If you might add a second or third EV in the future, a 22kW three-phase install lets one charger serve multiple vehicles faster — though a load-balanced pair of 7kW units may be a better solution.
A quick decision tree
Use this in order. Stop at the first "yes":
1. Are you wiring up a business car park, hotel or fleet depot? → 22kW. See the 22kW commercial range.
2. Do you already have three-phase electricity AND drive a car that accepts 22kW (Zoe, Megane E-Tech, Smart #1/#3)? → 22kW.
3. Everything else (i.e. typical UK home, single-phase supply, 11kW-or-lower car) → 7kW. See the 7kW home range.
Common questions
Will a 22kW charger damage my car?
No. The car only ever pulls what its on-board charger can accept, regardless of the unit's rating. Plugging a Tesla into a 22kW charger is perfectly safe — the car will just take 11kW and ignore the rest.
Can I install a 22kW charger and have it throttle to 7kW for now, then upgrade to three-phase later?
Technically yes, but it usually makes more financial sense to install a 7kW unit now, and replace it with a 22kW unit when (and if) you upgrade to three-phase. Charger hardware depreciates, technology improves, and you save the upfront premium.
What about 11kW chargers?
11kW chargers exist for three-phase supplies but throttle to 7.4kW on single-phase, just like 22kW units. They are a sensible middle ground for homes with three-phase but cars that max out at 11kW.
Does the OZEV grant cover 22kW chargers?
The home £350 grant is for residential installs, which are typically 7kW. For business installs, the Workplace Charging Scheme (WCS) covers 22kW units up to £350 per socket. See our OZEV grant guide.
Do I need a DNO application for a 7kW charger?
Yes, but it is just a notification — not an approval that delays the install. Your installer handles it.
What is the fastest home charger I can get on a single-phase UK supply?
7.4kW. Anything sold as faster will throttle to 7.4kW. The only way to charge faster at home is to upgrade to three-phase.
Pick the right charger
For a single-phase UK home, browse our 7kW home charger range — including the Ohme Home Pro, Easee One, myenergi Zappi and Tesla Wall Connector.
For a business car park or three-phase property, see our 22kW commercial charger range, or read our deep-dive on the best 22kW chargers for business car parks.
Need help? Call 0330 043 8012 or email adam@echargersuk.co.uk — we'll help you confirm whether your supply is single- or three-phase before you order.