How can grid operators limit charging?
The transformer reaches its limit. A signal from the distribution operator reaches the wallboxes in the street.
For forty minutes, every controlled wallbox drops to a guaranteed minimum. Then the signal ends.
The questionWhen may a grid operator step in, and what is the driver still guaranteed?
A worked example: Germany
In Germany, non-public charge points above 4.2 kW at low voltage that went into operation since 1 January 2024 count as controllable devices. When an overload threatens, the distribution operator may reduce their power for a time, but each device directly controlled keeps at least 4.2 kW. Behind an energy management system, several devices share a minimum calculated with a simultaneity factor.
The calculation is shown in Load management, stop 06.
- Marketprice per quarter hour
- Supplierdynamic contract
- Carcharges when cheap
- Transformernear its limit
- Grid operatorcontrol signal
- Wallboxdown to the minimum
In the German rules, a grid operator's reduction takes priority over market-based control where they conflict.
Flexibility as a service
Beyond direct control, EU law opens the markets for congestion management to small devices: RED III asks Member States to let electric cars and home batteries take part, also through . A grid operator can then buy flexibility instead of ordering it.
Check your understanding
3 questions. Answer all of them to complete this stop. Each answer explains itself.
In Germany, which newly installed charge points count as controllable devices since 2024?
The rules cover non-public charge points above 4.2 kW at low voltage; public charge points are excluded.
What has priority when a grid signal and a market signal conflict, in the German rules?
The rules require the operator to give the grid operator's reduction priority over conflicting market-based control.
How can a grid operator use flexibility without ordering it?
RED III opens congestion management and flexibility markets to small devices, also via aggregation.
- Aggregator A company that pools many small devices, such as cars and home batteries, so they can take part in electricity markets. Stop 02 Glossary
- Bundesnetzagentur: BK6-22-300, Annex 1, sections 2.4 and 4.5. https://www.bundesnetzagentur.de/DE/Beschlusskammern/1_GZ/BK6-GZ/2022/BK6-22-300/Beschluss/BK6-22-300_Beschluss_Anlage1.pdf?__blob=publicationFile&v=1. Checked 09 Oct 2026.
- Bundesnetzagentur: BK6-22-300, Annex 1, sections 2.4 and 4.5. https://www.bundesnetzagentur.de/DE/Beschlusskammern/1_GZ/BK6-GZ/2022/BK6-22-300/Beschluss/BK6-22-300_Beschluss_Anlage1.pdf?__blob=publicationFile&v=1. Checked 09 Oct 2026.
- Bundesnetzagentur: BK6-22-300, Annex 1, sections 2.4 and 4.5. https://www.bundesnetzagentur.de/DE/Beschlusskammern/1_GZ/BK6-GZ/2022/BK6-22-300/Beschluss/BK6-22-300_Beschluss_Anlage1.pdf?__blob=publicationFile&v=1. Checked 09 Oct 2026.
- Bundesnetzagentur: BK6-22-300, Annex 1, sections 2.4 and 4.5. https://www.bundesnetzagentur.de/DE/Beschlusskammern/1_GZ/BK6-GZ/2022/BK6-22-300/Beschluss/BK6-22-300_Beschluss_Anlage1.pdf?__blob=publicationFile&v=1. Checked 09 Oct 2026.
- EUR-Lex: Directive (EU) 2023/2413 (RED III), Article 20a inserted into Directive (EU) 2018/2001. https://eur-lex.europa.eu/eli/dir/2023/2413/oj. Checked 09 Oct 2026. © European Union, reused under Commission Decision 2011/833/EU.