When choosing an EV charger, you will see there are 7kw and 22kw options available. Here’s what you need to know to decide which one is right for you.
What Do 7kW and 22kW Mean?
- 7kW Charger:
- Uses single-phase power (standard in most UK and European homes).
- Delivers 7 kilowatts of power.
- Typical charging speed: ~25–30 miles of range per hour meaning a full charge in most cases between 7-8 hours.
- 22kW Charger:
- Requires three-phase power (available in some homes, standard in many commercial/industrial buildings).
- Delivers 22 kilowatts of power.
- Typical charging speed: ~75–80 miles of range per hour meaning a full charge in most cases between 3-4 hours.
Power Supply Requirements
- 7kW: Compatible with most residential electrical systems.
- 22kW: Requires a three-phase electricity supply, which many homes don’t have by default.
Is It Worth Upgrading to a 3-Phase Supply for a 22kW EV Charger?
As most homes do not have a 3-phase supply, we often get asked whether it’s worth upgrading to a 3-phase electricity supply just to install a 22kW electric vehicle (EV) charger. In our opinion, for most households, it’s probably not worth it — and here’s why.
Upgrading to a 3-phase supply can be expensive, with costs typically in the region of £3,000 to £15,000, depending on your location and the complexity of the installation. For most people, this level of investment is hard to justify, especially when a standard 7kW home charger is more than sufficient for daily use.
With a 7kW charger, you can simply plug your EV in overnight, and by the time you wake up, your car will be fully charged and ready to go — hassle-free!
What’s more, many energy providers (such as Octopus Energy) offer cheaper off-peak electricity rates overnight, which can reduce your charging costs. This makes overnight charging with a 7kW charger not only convenient, but also cost-effective.
Unless you have a specific need for ultra-fast home charging — such as running multiple EVs with high daily mileage — sticking with a single-phase supply and a 7kW charger is likely the most practical and economical option but if you would like to discuss this with us, just give us a call, our engineer team will happily talk this through with you.