Home EV Charger Guide: Wallbox Installation, 11 vs 22 kW and Costs

Socket, 11 kW or 22 kW: the options compared

The figures assume the usual European 230 V per phase. Wikipedia gives 3.68 kW for a Schuko socket at 230 V and 16 A, and 7.4 kW for single-phase charging at 32 A.

Why the car decides the charging speed

The wallbox does not charge the battery directly. On AC charging, it supplies power to the car's on-board charger, which converts it to DC for the battery. That charger has its own limit. ADAC's rule is simple: if the on-board charger supports up to 16 A on one, two or three phases, an 11 kW wallbox is fully sufficient. Only a 32 A on-board charger makes a 22 kW wallbox worth considering.

A car with a single-phase on-board charger cannot use all three phases of an 11 kW wallbox. Check the AC charging power in the car's specifications before choosing. You can find the battery size and other data for each model on our electric cars pages.

How long home charging takes

Charging time is roughly the energy you need divided by the charging power, which is the formula ADAC uses. The table applies it; real sessions take longer because of charging losses. ADAC gives 5 to 8 hours as typical for a full charge at 11 kW.

The pattern is clear. With 11 kW, almost any car is full by morning. A 22 kW wallbox saves time mainly for people with very high daily mileage or several cars sharing one charger. ADAC points out that 11 kW is gentler on the battery, while 22 kW has slightly lower charging losses because sessions are shorter.

What a wallbox costs

ADAC's figures for the unit:

ADAC says the price depends mainly on the manufacturer and the features, not on the charging power.

Installation is often the larger part. ADAC's installation service for single-family houses listed three typical packages in 2026:

Digging work and a new meter cabinet are extra. ADAC also notes that if the property's total power demand exceeds 30 kW, the grid operator charges a connection contribution, about €500 on average (ADAC, 2025). To see how a wallbox changes the cost of running an electric car, add it to the purchase costs in our cost of ownership calculator.

Installation step by step

1. Check your supply. Find out whether the house has a three-phase connection and enough spare capacity. ADAC offers a video check for €89 or an on-site check for €199 (2026); any electrician can do the same assessment.
2. Choose the wallbox to match the car. For most cars, an 11 kW unit. Decide on a fixed (tethered) cable or a socket for your own cable.
3. Get a quote from a qualified electrician. In Germany only a qualified electrician may install and commission a wallbox; self-installation is not allowed.
4. Notify the grid operator. The electrician usually does this, but confirm it is in the quote. The grid operator is not the same company as your electricity supplier.
5. Install the protection devices. ADAC lists protection against DC fault currents above 6 mA and AC fault currents above 30 mA as mandatory. Many wallboxes have the DC protection built in.
6. Commission and test. The installer sets the maximum current, the app and any load management.

Rules in Germany: notification, approval and grid control

Rules on home chargers are set nationally, so check with your local grid operator or electrician if you live elsewhere. Germany is a well-documented example:

• Every wallbox must be notified to the grid operator before installation, whatever its power. This has applied since March 2019 under the Low Voltage Connection Ordinance (NAV), and also covers mobile chargers on adapters. Notification is free.
• Above 11 kW, approval is needed. The grid operator must respond within two months; after approval you have four months to install. A 22 kW wallbox limited to 11 kW usually needs no approval.
• Controllable charging since 2024. New wallboxes above 4.2 kW installed since 1 January 2024 must be controllable by the grid operator, which may reduce them to 4.2 kW for short periods in an emergency. In return, the grid operator may not refuse or delay the connection because of possible grid overload.
• Unreported wallboxes can lead to claims for damages and to the power being cut off, ADAC warns.

Tenants need the landlord's consent before installing a wallbox. In flats owned by several parties, ADAC says the owners' association can no longer block a charging point for an owner's parking space under the WEMoG law, although the other owners still have a say in how it is installed.

Charging from a normal socket

A portable charger plugged into a household socket is useful when travelling or as a backup. For daily charging, ADAC says it is not to be recommended. Even at the socket's maximum of about 3.7 kW, adding 40 kWh takes almost 11 hours, and many evenings are shorter than that.

Note that in Germany the notification duty also covers mobile chargers used with adapters. If you plan to rely on a socket for a while, have an electrician check the circuit first and use the charger supplied or approved by the car maker.