Connecting a wallbox in Prague: what the grid operator needs

Why anyone cares

From the grid's point of view a charger is a large appliance. An 11 kW wallbox draws roughly as much as an electric cooker at full tilt. The distribution operator needs to know it exists so the load in your street adds up.

In Prague and the surrounding area the operator is PREdistribuce. Note this is not your electricity supplier — you choose and change the supplier, the distribution operator comes with your address.

Three scenarios, you are in one of them

1. The existing main breaker is enough

The most common case for houses with reasonable headroom. The wallbox is fitted, its output is set so it stays under the existing breaker, and the operator simply gets a notification by e-mail. No application, no waiting for approval.

2. The main breaker needs raising

If the main breaker is small and charging would trip it, you file a request to change the reserved capacity. The operator assesses it and issues a statement, and your monthly standing charge changes too — it scales with breaker size. The wallbox notification is then filled in during the technician's visit.

This decides a monthly cost for years ahead, so it is worth checking whether the increase is genuinely needed. Often it is not.

3. The tariff changes as well

If you want cheaper charging, you switch to the tariff intended for electric vehicles. It can be arranged together with the step above. We cover it separately in the article on tariff D 27d.

How to often avoid raising the breaker

• Set the wallbox to a lower output. A car charging at 7.4 kW instead of 11 kW finishes overnight just the same — the difference is between "done at two" and "done at four".
• Dynamic load management. The charger measures the whole house and backs off when you switch the oven on, so the breaker cannot trip.
• Charge at night, when the house draws little else.

Dynamic load management is also usually a condition of the grant, so it pays off twice.

What we do

At the site visit we look at the consumer unit, read the main breaker rating and work out what it will carry. Then we tell you straight which of the three scenarios applies and what it means in time and money. We handle the operator paperwork.