South Africa’s nuclear history is rich and as the country ramps up its ‘just energy transition’, nuclear looks like a solid option when moving away from coal-generated power.

Last year South Africa shut down Koeberg unit 2 for maintenance, Koeberg is a central figure in South Africa’s nuclear history and future. The power station proves that nuclear power is a viable solution to coal, its two units have reliably provided power to the Western Cape since 1984.

During February 2025 South Africa opened its nuclear programme to bids from Russia and Iran, a controversial move amidst tensions with the United States. A report by BizNews says that nuclear power still looks unlikely for South Africa due to time and cost constraints. Despite this, the South African National Energy Development Institute (SANEDI) still argues that nuclear is the best move for large generation competing with coal.

Here is a closer look into the nuclear power in South Africa (source: World Nuclear Association):

A brief history

1944: USA and UK requested forecasts from South Africa on its potential to supply mineable uranium. This led to the formation of the Uranium Committee in 1945, and, in 1948, the Atomic Energy Board (AEB) was formally established to oversee uranium production and trade. 

1959:  The government approved the creation of a domestic nuclear industry and planning began the next year on building a research reactor, in cooperation with the US Atoms for Peace programme.

1961: The Pelindaba site –  South Africa’s main nuclear research centre – near Pretoria  was established

1984-1985: The Koeberg plant was built by Framatome and commissioned. The Koeberg plant is owned and operated by ESKOM.

Why are the nuclear reactors in Cape Town?

South Africa’s main coal reserves are concentrated in Mpumalanga in the northeast, while much of the load is on the coast near Cape Town and Durban. Moving either coal or electricity long distance is inefficient, so it was decided in the mid-1970s to build some 1800 MWe of nuclear capacity at Koeberg near Cape Town.

Electricity generation in South Africa

• Total Generation (2021): 244 TWh
• Generation Mix:
  • Coal: 210 TWh (86%)
  • Nuclear: 12.4 TWh (5%)
  • Wind: 8.4 TWh (3%)
  • Hydro: 6.8 TWh (3%)
  • Solar: 6.7 TWh (3%)
• Total Consumption: 193 TWh
• Per Capita Consumption: ~3300 kWh (2021)
• Eskom’s Role:
  • Provides 95% of South Africa’s electricity
  • Supplies 40% of Africa’s total electricity
• Installed Capacity (2022):7 GWe
  • Coal-fired stations: 39.8 GWe
• Nuclear Capacity: 1840-1860 MWe since 1986

Proposed Nuclear Expansion: Two 1200 MWe units at Duynefontein or Thyspun.

Uranium in South Africa

• Main Source: By-product of gold and copper mining
• Key Players and Operations:
  • Nufcor and AngloGold Ashanti: Peak 6,000 tU/year (1960), now ~200 tU/year.
  • Cooke and Ezulwini (Sibanye Gold): Peaked at 69 tU (2014), now stockpiled.
  • West Rand Tailings (Sibanye): 38,190 tU in reserves.
  • Beatrix (Sibanye Gold): 4,490 tU reserves.
  • Buffelsfontein & Vaal River: Peaked at 532 tU (2013).
  • Shiva/Dominion Reefs: 51,000 tU, auctioned in 2019.
  • Karoo Project: 21,930 tU, abandoned (2018).
  • Namakwa/Henkries: Explored since 1979, no significant development.
• Challenges and Trends:
  • Declining production (582 tU in 2011 → 200 tU in 2022).
  • Economic constraints leading to mine closures.
  • Environmental concerns (acid mine drainage, radionuclide pollution).

Waste management and decommissioning

• Regulatory Framework:
  • 2008 National Radioactive Waste Disposal Institute Act: Established NRWDI (2014).
• Waste Disposal Facilities:
  • Vaalputs Repository (since 1986): Low & intermediate-level waste from Koeberg.
  • Pelindaba: Additional waste from hospitals, industry, and Necsa.
• Used Fuel Management:
  • Koeberg stores used fuel on-site.
  • 2015: Holtec contracted to supply HI-STAR 100 casks (for transport & storage).
  • 2008: Eskom planned to reprocess fuel overseas for MOX fuel.

Research and development

• Necsa Overview:
  • Established in 1999 from AEC.
  • Focuses on nuclear energy, radiation research, and materials processing.
• Safari-1 Research Reactor:
  • 20 MWt reactor at Pelindaba.
  • Supplies 25% of the world’s Mo-99 (medical isotopes).
  • Converted from HEU to LEU (2009-10).
  • Multipurpose Reactor approved (2021) to replace Safari-1.
• Klydon Corporation:
  • Develops Aerodynamic Separation Process (ASP) for isotope separation.
  • Focus on uranium enrichment, silicon-28, zirconium-90.
• Pebble Bed Modular Reactor (PBMR):
  • Developed 1993-2010 as a high-temperature gas-cooled reactor (HTR).
  • 244 billion ($1.3 billion) invested by government, Eskom, and others.
  • 400 MWt Brayton cycle → later revised to 200 MWt (80 MWe) steam cycle.
  • Halted (2010) due to lack of investors, high costs, and deadline failures.
• PBMR Legacy & Future Reactor Development:
  • 2013: US funding application for 165 MWe HTR.
  • 2016: Eskom revived PBMR research for simplified design & process heat use.
  • New 150 MWe Advanced HTR:
    • 50 MWe pilot plant (mid-2020s), full-scale (2030s).
    • Concrete pressure vessel, helium coolant, pebbled fuel, molten salt circuit.
    • Gas turbine (40%) + steam cycle (60%) = 60% efficiency.
  • Steenkampskraal Thorium Limited (STL Nuclear) and HTMR:
    • Developing HTMR-100 (35 MWe / 100 MWt) for electricity and process heat.
    • Derived from Jülich and PBMR designs, uses thorium-based fuel cycle.
    • Variants: HTMR-30 (10 MWe) & microreactor (10 MWt).

Did you know? South Africa is the only country to develop nuclear weapons and voluntarily give them up!

In 1993, President Frederik Willem de Klerk announced that six nuclear weapons and a seventh uncompleted one had been dismantled. In 1995, the International Atomic Energy Agency (IAEA) was able to declare that it was satisfied all materials were accounted for and the weapons programme had been terminated and dismantled.