Why do some chargers share power between plugs?
Charger 1 has 300 kW and two outlets. A car at 15% takes 225 kW. A second car connects to the other outlet.
The first car's power drops, the second starts at about 120 kW. Ten minutes later the first car is at 70% and takes much less.
The questionHow does one charger divide its power, and who decides?
A composed example of one charger and four moments of one morning.
A car takes full power only for part of a session; as the battery fills, the power falls (see the charging curve). The national charging study for Germany models it that way: the highest power at about 30% , falling steadily towards 100%. With sharing, power that one car no longer needs goes to the next car, and a second car can start right away instead of waiting for a free charger.
Who decides
The charger's controller divides the power between its outlets within the charger's total. calls this load balancing within the charge point: the charger works with a fixed limit and sets the schedule for each connector. On top of that, the backend can set a limit for the whole charger, for example when the grid connection is shared with other chargers. According to ADAC, most stations simply halve the power when two cars are connected, and more and more distribute it dynamically by need; this charger does the latter. That is , the subject of its own path.
Check your understanding
3 questions. Answer all of them to complete this stop. Each answer explains itself.
As a battery fills, it takes less power. Power it no longer needs can serve the second car.
Each car reports what it can take, the controller allocates. A site or backend limit can cap the charger as a whole.
At 70%, car A is in the falling part of its charging curve. The power it releases goes to car B.
- OCPP Open Charge Point Protocol: the open protocol between a charger and its operator's backend. EV charging fundamentals, stop 03 Glossary
- Load management Shares a site's grid connection between the cars charging at the same time. EV charging fundamentals, stop 04 Glossary
- State of charge How full the battery is right now, in percent; not to be confused with the state of health. eMobility and EV basics, stop 02 Glossary
- Nationale Leitstelle Ladeinfrastruktur and Reiner Lemoine Institut: Ladeinfrastruktur nach 2025/2030: Szenarien für den Markthochlauf, new edition 2024, section 2.2.1: the charging curve used in the model. https://reiner-lemoine-institut.de/wp-content/uploads/2024/06/Studie_Ladeinfrastruktur-2025-2030_Neuauflage-2024.pdf. Checked 13 Oct 2026.
- Open Charge Alliance: OCPP 1.6 edition 2 (2017), section 3.13.4 Smart Charging Use Cases: load balancing within a charge point, and section 3.13.3: ChargePointMaxProfile for the whole charge point; free download. https://openchargealliance.org/download-ocpp/. Checked 13 Oct 2026.
- Open Charge Alliance: OCPP 1.6 edition 2 (2017), section 3.13.4 Smart Charging Use Cases: load balancing within a charge point, and section 3.13.3: ChargePointMaxProfile for the whole charge point; free download. https://openchargealliance.org/download-ocpp/. Checked 13 Oct 2026.
- ADAC: Noch schneller Schnellladen, press release, 7 August 2025: power split between two cars at one station. https://presse.adac.de/meldungen/adac-ev/technik/noch-schneller-schnellladen.html. Checked 13 Oct 2026.