7kW vs 22kW Home EV Charger: Which Do You Actually Need?
The instinct is reasonable: more kilowatts, faster charging, buy the bigger one. But EV charging has a bottleneck many buyers don’t find out about until after the money’s spent, and it isn’t the wallbox on your wall.
What actually decides your charging speed
Every EV has an onboard charger built into the car. Its job is converting the AC power from your wall unit into the DC your battery stores. That component has a fixed maximum rating, and it caps your AC charging speed no matter what you plug into.
Plug a car with an 11 kW onboard charger into a 22 kW wallbox and it charges at up to 11 kW. The extra capacity does nothing. You’ve paid for a bigger unit and a heavier circuit to deliver power the car won’t accept.
The list of EVs that accept 22 kW AC is relatively short. If your car isn’t on it, a 22 kW charger is capacity you can’t use.
The comparison
| Feature | 7 kW single-phase | 11 kW three-phase | 22 kW three-phase |
|---|---|---|---|
| Supply required | Single-phase, which is what most homes have | Three-phase | Three-phase |
| Current draw | 32 A | 16 A per phase | 32 A per phase |
| Range added per hour (approx.) | About 40 km | About 60 km | About 120 km |
| Time to add 60 kWh (approx.) | About 8 to 9 hours | About 5.5 to 6 hours | About 3 hours |
| Cars that can use full speed | Most EVs | Many modern EVs | Relatively few |
| Install complexity | Dedicated circuit | Requires three-phase supply | Three-phase plus a heavier circuit |
Range and time figures are rough estimates we’ve worked out from power and typical efficiency. They assume the car can accept the charger’s full output and ignore the slowdown near a full battery, and they vary by vehicle. Check the row about which cars can use full speed first.
The counterintuitive part: 11 kW can be slower than 7 kW
This catches people out, and it’s why “bigger number equals faster” fails as a rule of thumb.
An 11 kW three-phase charger delivers 16 amps on each of three phases. If your car has a single-phase onboard charger, common on some more affordable EVs, it can only draw from one of those phases. Sixteen amps at 230 volts is about 3.7 kW.
A 7 kW single-phase charger delivers 32 amps on one phase. Same car, roughly 7.4 kW. Nearly twice as fast as the 11 kW unit.
A 22 kW charger also runs 32 amps per phase, so a single-phase car gets its full 7.4 kW there too. But it needs three-phase supply to deliver something a 7 kW unit already achieves for that vehicle.
Work out what your car can actually take
- Find the onboard AC charger rating in your owner’s manual or spec sheet, sometimes listed as “AC charging” or “onboard charger”.
- If it’s around 7.4 kW or less, your car is most likely single-phase. A 7 kW charger gives you its maximum speed.
- If it says 11 kW, you most likely have a three-phase onboard charger. An 11 kW unit matches it; 22 kW adds nothing.
- If it says 22 kW, you’re in the minority that can use a 22 kW charger, assuming your home has three-phase supply.
- Find out whether your home is single or three-phase. Your electrician can confirm it on site. From the outside of the switchboard, one main switch generally means single-phase and three linked switches generally means three-phase, but look only and don’t open the board.
That first number is your ceiling. Everything else is about whether your home can deliver up to it.
What changed with Energex on 1 October 2026
Charger speed isn’t only a question of what the car accepts. The network has rules too, and in South East Queensland they changed recently.
From 21 February 2024, Energex required single-phase chargers rated above 20 A at most homes to be a managed connection. According to Energex’s EV charger connections page, that requirement (clause 8.14.4(b) of the Queensland Electricity Connection Manual) was withdrawn from 1 October 2026, so EV chargers no longer have to comply with it, and new applications for the managed options have stopped.
Energex says that after 1 October 2026 you can still choose to connect a dedicated EV charger to an eligible controlled load tariff, subject to your retailer’s eligibility rules. Otherwise, a single-phase charger can run on your standard tariff, and a three-phase 22 kW charger is an option where the home is wired for three-phase. If you’re reading older advice, including older guides online, that says a 7 kW home charger must have network device management, it’s out of date.
None of that changes which charger suits your car, but the tariff choice is worth discussing when you book. Our guide to EV charger installation requirements in QLD covers the wider install.
Do the maths on your actual driving
Charging speed matters less at home than many buyers expect, because the car is parked for so long.
At 7 kW you’re adding roughly 40 km of range per hour. A 100 km day is about a 2.5-hour charge. Even 200 km, a heavy day for most drivers, is around five hours, comfortably done overnight.
Faster charging only matters when you need a large top-up inside a narrow window. Some households need that. Before paying for it, think about how often it actually happens to you. If you’re wondering whether you need a wallbox at all, see can you charge an EV from a normal power point.
What three-phase actually involves
Before booking EV charger installation, this is the constraint worth understanding.
If your home is single-phase and you want 11 kW or 22 kW, you need a three-phase supply upgrade, which is a much bigger job than installing a charger. It involves Energex, changes to the supply and switchboard work, not just a different wallbox.
Our guide to three-phase versus single-phase power explains the difference, and a switchboard inspection tells you what your board can handle before you order anything.
When 22 kW makes sense
- Your car actually accepts 22 kW AC, checked on the spec sheet and not assumed
- You already have three-phase supply, so there’s no upgrade to justify
- Several EVs sharing one charger, where total throughput matters more than individual speed
- Tight charging windows: commercial use, rideshare, or a vehicle that turns around several times a day
- Commercial or strata installations, where load management across several bays changes the calculation
Outside those situations, the extra cost buys capability that sits unused.
Before you buy any charger
- Confirm your car’s onboard AC charger rating. It caps everything downstream
- Confirm whether your home is single or three-phase
- Get the switchboard assessed before ordering, not after
- Ask whether a controlled load tariff makes sense for you, and check your retailer’s eligibility rules
- Most new EVs sold in Australia use the Type 2 plug for AC charging, so choose on capability, not badge
- Have it installed by a licensed electrician. A wallbox is fixed electrical work, with no homeowner exemption
What we recommend
For most Gold Coast and SEQ homes, from Palm Beach and Burleigh Heads out to Robina: a 7 kW single-phase charger on a dedicated circuit. It gives full speed for many cars on the road, works with the supply most homes already have, and can add enough range overnight to cover a normal driving day.
We’ll tell you when the bigger unit is worth it. Often it isn’t, and recommending it anyway would mean charging you for a three-phase upgrade your car can’t take advantage of.
Frequently asked questions
Will a 22kW charger charge my car faster than a 7kW one?
Only if your car’s onboard charger can accept more than about 7 kW and your home has three-phase supply. The onboard charger is a fixed component in the vehicle and caps AC charging speed regardless of the wallbox. Many EVs top out at 11 kW AC, and relatively few accept 22 kW, so check the spec sheet first.
Can a Tesla use a 22kW charger?
It can plug into one, but it won’t necessarily charge faster. Tesla lists the Model 3 onboard charger at 11 kW, so on a 22 kW unit it charges at up to 11 kW and the extra capacity goes unused. Check the maximum charge rate shown in your own car’s charging menu.
Is an 11kW charger always faster than a 7kW one?
No, and this catches people out. An 11 kW three-phase unit delivers 16 A per phase. A car with a single-phase onboard charger draws from one phase only, giving about 3.7 kW. The same car on a 7 kW single-phase charger draws 32 A and gets roughly 7.4 kW, nearly twice as fast.
How do I find out what my car’s onboard charger is rated at?
Check the owner’s manual or manufacturer spec sheet, usually listed under “AC charging” or “onboard charger”. Ratings of about 7.4 kW or below generally mean a single-phase onboard charger; 11 kW or above generally means three-phase. That figure is your maximum home AC charging speed, whatever wallbox you buy.
Do I need three-phase power for a home EV charger?
Not for a 7 kW charger, which runs on the single-phase supply most homes already have. Three-phase is needed for 11 kW or 22 kW units, and upgrading to three-phase is a substantial job involving Energex and changes to the supply, not just a switchboard change.
Will a 7kW charger be enough for daily driving?
For most households, yes. At roughly 40 km of range added per hour, a 100 km day charges in about 2.5 hours and even a 200 km day is around five hours, comfortably overnight. Faster charging only matters when you need a large top-up in a narrow window.
Does a 7kW charger still need Energex device management in Queensland?
Not for new installs from 1 October 2026. Energex says the requirement for single-phase chargers over 20 A to be a managed connection was withdrawn on that date, and new applications for the managed options have stopped. You can still choose to put a dedicated charger on an eligible controlled load tariff, subject to your retailer’s rules.
Not sure which your home can support? Call us. We check the switchboard and tell you what’s worth installing.