Koeberg Unit 2 passes its 10-year leak test. When is it back?
Eskom says Koeberg Unit 2 passed its Integrated Leak Rate Test, the 10 yearly check that the reactor containment is sealed. Maintenance continues before it returns to service, with no date given.
Koeberg's Unit 2 has passed its Integrated Leak Rate Test, the check that the reactor's containment building is still sealed and strong, Eskom said on Tuesday, 10 November 2026. An independent, internationally recognised utility confirmed the unit met all the acceptance criteria (Eskom).
Unit 2 isn't back online yet. Eskom said its outage and maintenance work will continue as planned before it returns to service, and it did not give a date (Eskom).
What is the Integrated Leak Rate Test?
It is a mandatory regulatory test done every 10 years. The containment building is pressurised to the level expected in an accident to check that it is leak tight and can hold in radioactive material (Eskom). The containment is one of the station's most important safety barriers (Eskom).
Why does it matter?
The National Nuclear Regulator (NNR) approved a 20 year operating licence extension for Unit 2 on 6 November 2025, and Eskom says passing the test supports that long term operation (NNR; Eskom). The licence extension came just days before the old licence was due to expire on 9 November 2025 (The Citizen).
Eskom generation head Bheki Nxumalo said Koeberg delivers "some of the lowest cost per unit of energy across our fleet" (Engineering News).
Has Unit 1 done the same test?
Yes. Unit 1 passed the same test in July 2025, during its Outage 127, and Eskom says it continues to run safely (Eskom; Eskom).
What has the regulator said about the outage?
The NNR's Koeberg page says it told Eskom to suspend all radiography work during the Unit 2 maintenance window, known as Outage 227, after recurring radiography incidents created a risk of uncontrolled worker exposure. The suspension was later lifted (NNR).
Key dates
| Event | Date |
|---|---|
| Unit 1 passes leak rate test | July 2025 |
| NNR approves 20 year licence for Unit 2 | 6 November 2025 |
| Unit 2 passes leak rate test | Announced 10 November 2026 |
| Unit 2 return to service | No date given |
FAQ
Is Koeberg Unit 2 back online?
Not yet. Eskom said outage and maintenance work on Unit 2 continues as planned before it returns to service, and it gave no date.
How often is the Koeberg leak rate test done?
Every 10 years. It is a mandatory regulatory test of the containment building.
How long can Koeberg Unit 2 operate?
The National Nuclear Regulator approved a 20 year long term operation licence for Unit 2 on 6 November 2025.