A wallbox charges over dwell time, not in minutes.

It hangs on the wall of a garage, in an underground car park or at a depot. Where there is no wall, a pedestal carries it. In size and weight it sits close to a consumer unit. A qualified electrician wires it to a dedicated circuit.

Alternating current is AC. In this case the charger sits inside the vehicle and turns the supply into the direct current the battery needs. The wallbox releases the current, watches the circuit and measures what passes through. How much the car draws is up to the car.

The usual ratings are 3.7 kW single-phase, 11 kW three-phase and 22 kW three-phase. In Germany 11 kW is the norm, and anything above it needs the grid operator’s approval. A car with a 60 kWh battery fills overnight at 11 kW. Many vehicles accept only single-phase or 11 kW anyway.

In Europe a wallbox carries a Type 2 socket or a fixed Type 2 cable. The socket is more flexible, the fixed cable more convenient. Either fits every electric car sold in Europe. A card reader comes as standard on wallboxes meant for several users.

The rapid charger at the motorway services works with direct current, DC. Its charger sits in the pillar and feeds the battery directly. It delivers 50 to 400 kW and does in twenty minutes what a wallbox needs hours for. Hardware and grid connection cost many times as much, frequently including a transformer of their own.

Wherever vehicles stand for a long time, a wallbox is enough. Underground car parks, depots and staff car parks are its territory. Dwell time does the charging, not power. Ten wallboxes still cost less than a single rapid charger.