Koeberg Unit 1 returns to service in South Africa

Eskom has confirmed that Unit 1 of the Koeberg Nuclear Power Station has returned to service and is synchronized to the national electricity grid. The unit was previously shut down following an electrical disturbance on 16 October 2026.

The disturbance occurred during testing activities related to the planned maintenance outage of Unit 2. An investigation revealed that a conservative protection relay setting caused the system to exceed predefined tolerance limits, triggering the automatic opening of the unit’s 400 kV and 24 kV breakers. Eskom stated that the protection system operated as designed to ensure the safe shutdown of the plant and emphasized that there was no impact on nuclear safety.

While Unit 1 is now stable and operational, Unit 2 remains offline for its scheduled maintenance programme.