Eskom’s Koeberg unit hits 99.4% output after yearlong run   

South Africa’s state-owned power utility, Eskom Holdings SOC Ltd., announced that Unit 2 of Koeberg Nuclear Power Station achieved a near-perfect run of 365 consecutive days of uninterrupted power generation following significant technical upgrades.

The unit maintained an average energy availability factor of 99.4%, delivering roughly 946 megawatts to the South African national grid. 

The milestone underscores the strategic role of Koeberg Nuclear Power Station in bolstering electricity supply in the Cape Town region.

By reducing dependency on coal-fired plants from northern provinces, the facility helps stabilize the grid and limits exposure to power disruptions. “Nuclear power provides low-emission electricity while keeping generation costs stable,” the utility said.

Grid stability and maintenance 

Following a comprehensive overhaul, including the replacement of steam generators, Unit 2 returned to service on Dec. 30, 2024, and has operated continuously since March 9, 2025. Eskom’s Group Executive for Generation, Bheki Nxumalo, credited the achievement to the skill of engineers, operators, and support staff. 

Unit 2 is projected to operate for 412 days before scheduled maintenance on 26 April 2026. While this falls short of the 454-day record set in 2022, Eskom said it demonstrates progress in reducing unplanned outages. The maintenance is crucial for protecting recent investments and ensuring reliability for the next 20 years.

Eskom noted that the steady output directly benefits households and businesses, easing grid pressure. The performance coincides with approximately 300 days without load shedding this year, reflecting improved generation and regional energy stability.

Strategic role of Koeberg 

Eskom, wholly owned by the South African government, operates across generation, transmission and distribution, and also trades power within the Southern African Development Community. 

As Africa’s only nuclear power station, Koeberg Nuclear Power Station remains a critical component of South Africa’s energy mix. Its pressurized water reactor and high-capacity turbines deliver baseload power, complementing renewable and coal-fired sources.

The facility also sits within a 3,000-hectare nature reserve, home to diverse wildlife, reinforcing Eskom’s commitment to environmental stewardship.

Leadership driving operational excellence 

Under CEO Dan Leseja Marokane, Eskom has focused on operational efficiency and strategic turnarounds. With nearly 30 years leading large-scale operations across energy, manufacturing, and resources, Marokane has overseen R100 billion ($5.82 billion) procurement budgets and capital expenditures of R60 billion ($3.5 billion) annually. 

His leadership has been central to Eskom achieving 300 days without load shedding, strengthening grid reliability, and supporting economic activity across South Africa.