Is it worth installing a 22kW home charging station?

If your home has three-phase power and your vehicle supports high-power AC charging, a 22kW charger can significantly reduce charging time. However, for most homes with single-phase power and vehicles with a charging power limit of 7kW or 11kW, installing a 22kW charger often does not result in actual speed improvements and instead increases equipment and renovation costs.

Understanding charging power, charging current, and home wiring conditions before making a decision can help you avoid unnecessary expenses.

How long does 22kW charging take?

Charging speed directly impacts the convenience of vehicle use. If you frequently need to recharge quickly, the charging speed of 22kW can be very appealing.

Under ideal conditions, a 22kW charging station can fully charge a vehicle with a moderate battery capacity in approximately 2–4 hours, while a 7kW device may take 4–8 hours. However, note that this speed depends on the maximum AC charging power supported by the vehicle's onboard charger. If the vehicle only supports 7kW AC, even switching to a 22kW charging station will not reduce the charging time.

How many amperes does 22kW charging require?

The formula for calculating charging power is: Power (kW) = Voltage (V) × Current (A) × Number of phases.

Using the common 230V voltage as an example, a 22kW three-phase charger requires approximately 32A of current per phase. A single-phase setup cannot achieve 22kW; upgrading to three-phase power is necessary for safe operation.

The core difference lies in charging speed and requirements for the power system.

7kW: Suitable for most households and vehicle models, with low installation costs and moderate charging speed

22kW: Requires three-phase power, charges 2-3 times faster, but the vehicle must support high-power AC charging 

Can a 7kW charging cable be connected to a 22kW charging station?

It can be physically connected, but the charging power will be limited by the cable's current-carrying capacity. For example, a 7kW-rated cable typically only supports a single-phase 32A current, so even when plugged into a 22kW charging station, the power will not exceed 7kW.

Which vehicle models support 22kW AC charging?

Currently, many models on the market still have a maximum AC power of 7kW or 11kW. Only some European brands and high-end electric vehicles support 22kW AC charging. Before installation, consult the vehicle manual or specifications to confirm the maximum AC charging power.

What size circuit breaker is required for a 22kW charging station?

Three-phase 22kW equipment typically requires a 32A circuit breaker per phase. In some regions, electrical codes recommend using a 40A circuit breaker to allow for safety margins. Installation must be performed by a qualified electrician to ensure that the wiring and protective devices comply with local standards.

Summary

If your home has three-phase power, your vehicle supports high-power AC charging, and you have frequent fast-charging needs, a 22kW charging station can enhance driving efficiency. However, for most residential users, a 7kW charging station is sufficient for daily use, offering lower installation costs, higher compatibility, and no need for significant modifications to the home electrical system.