In short
For most homes a 7.4 kW single-phase charger is enough, adding about 40 km per hour of charging and filling a 50 kWh battery in about 7 hours, within the off-peak period. With three-phase supply and a car that accepts it, 11 kW cuts the time. 22 kW only helps if the car accepts that power on AC, which is uncommon.
Indicative times
Simplified calculation without losses: in practice it takes somewhat longer, and charging slows near 100 %. If the car’s on-board charger accepts less power than the wall charger, the car’s limit applies.
| Power | Supply | Charge 0 to 100 % | Km added per hour |
|---|---|---|---|
| 3.7 kW | Single-phase, 16 A | About 14 hours | About 22 km |
| 7.4 kW | Single-phase, 32 A | About 7 hours | About 44 km |
| 11 kW | Three-phase, 16 A | About 4.5 hours | About 65 km |
| 22 kW | Three-phase, 32 A | About 2.5 hours | About 130 km |
How to choose
- Work out your daily mileage: for 50 km a day, a couple of hours at 7.4 kW is enough.
- Check your car’s maximum AC charging power in its specifications.
- Check whether your supply is single or three-phase.
- If contracted power is tight, choose a charger with dynamic load management.
- Think ahead: a three-phase or adjustable charger will suit your next car.