How can grid signals and prices steer charging?

When the grid operator may step in

Germany offers a concrete example. Non-public charge points of more than 4.2 kW connected at low voltage and put into operation since 1 January 2024 count as controllable devices.¹ When the grid is at risk of overload, the grid operator may reduce their power temporarily, but each device keeps a minimum of 4.2 kW.² Behind an energy management system, the minimum is set for the whole group, with a simultaneity factor.³

Capacity forecasts

Instead of a signal at the last minute, a grid operator or site owner can send a forecast. The Open Smart Charging Protocol, OSCP, was designed for this: it communicates the available capacity to the charging operator's backend, including a 24-hour prediction, so charging can be planned within it.⁵ OSCP 2.0 was released in 2020; the Open Charge Alliance no longer actively develops it.⁶

Prices that move charging

A price can steer too. EU law requires that customers with a smart meter can conclude a dynamic electricity price contract, at least with every supplier that has more than 200,000 customers.⁷ With prices that change by the hour, a controller can move charging into cheap hours, often at night or when the sun shines, as long as every car is full by its departure.

How charging fits into the power system as a whole is the subject of Energy and grid integration.