by Dr Tristen Taylor

Located 30 km north of Cape Town, the Koeberg nuclear power plant is almost at the end of its 40- year designed lifespan.

South Africa’s state owned electricity company wants to extend the plant’s life for another 20 years and has submitted its safety case to the nuclear regulator. At the end of 2022, Eskom released into the public domain a highly redacted version of that safety case. In March 2022, the International Atomic Energy Agency recommended a series of necessary improvements at Koeberg in order for the plant to be considered safe. Eskom seems to have downplayed or ignored key IAEA findings. This paper argues that the safety of Koeberg cannot be assured and the only reasonable course of action is to shut down Koeberg permanently.

Koeberg is South Africa’s only nuclear plant and its 1.8 GW generation potential is a key part of Eskom’s ability to provide power to the nation. The 100% state-owned electricity company is in trouble. Constant blackouts (loadshedding) plague the country for up to 12 hours a day. Eskom’s energy availability factor was around 90% in the 1990s. Today, the energy availability factor hovers around 54%, meaning that nearly half of its total nominal generation capacity of 46,446 MW is offline.1 It is also important to note that the electricity penetration rate has gone up from about 37% in 1994 to over 92% today.


Before civilian nuclear reactors, there were nuclear weapons. During the 1940s, the USA with assistance from Great Britain and Canada developed two atomic bombs, the Manhattan Project, in a climate of uttermost secrecy. The American government, military, intelligence services and the scientists themselves were understandably dedicated to preventing both Nazi Germany and the Soviet Union from first knowing about and then gaining critical information about the programme. Precisely because nuclear weapons were born in a culture of secrecy, a reluctance to full disclosure exists in the civilian nuclear industry: the apartheid government was extremely secretive about both Koeberg and its nuclear weapons. However, secrecy and withholding data are distinct, unnecessary and potentially catastrophic safety risks. In Lessons of Chernobyl: The Cultural Causes of the Meltdown, the Russian nuclear physicist Sergei Kapitz points out that the initial efforts to develop nuclear power were achieved under the military. Only later were nuclear plants transferred over to civilian control. Kapitz states of that transfer: Little institutional experience had accumulated through the developing years of the nuclear industry, and there was virtually no transfer of knowledge from those operating submarine reactors or producing plutonium to the civilian sector...The obsessive secrecy of the nuclear industry created a dangerous isolation. At the heart of a nuclear plant, within the reactor itself, is an inherently unstable process. The splitting of uranium-235 isotopes in a light-water reactor like Koeberg (breeder reactors use different isotopes) produces an incredible amount of energy and starts a powerful force. Once criticality is achieved the atoms will continue to split to the point of meltdown unless the reaction is controlled.

Control is achieved, primarily, through the use of control rods, made of neutron absorbing elements like boron, inserted into the reactor core to slow down the reaction or stop it completely. Water is both used to cool the reactor down and to generate the steam that drives a turbine which then produces electricity. In order to split atoms reliably and safely, nuclear plants have and will continue to become increasingly complex. Each nuclear accident, large or small, brings about a learning that is incorporated into existing and new plants. The first nuclear accident was in May 1945 at Los Alamos, the site of America’s nuclear weapons programme. Out of a total of an estimated 174 accidents8 from 1947 to 2014, six were reactor core meltdowns and 24 were major accidents. The total number of reactors providing electricity to the grid ever built, including those under construction, is 667.9 Accidents involving either partial or complete meltdowns are:

1952: Chalk River, Idaho, USA. Partial meltdown. 1969: Lucens, Vaud, Switzerland. Partial meltdown. 1978: Three Mile Island, Pennsylvania, USA. Partial meltdown. 1986: Chernobyl, Kiev Oblast, USSR. Complete meltdown. 1989: Saint-Laurent, Saint-Laurent-Nouan, France. Partial meltdown. 2011: Fukushima, Fukushima Prefecture, Japan. Complete meltdown.

Learnings from accidents, increased regulatory oversight and advancements within the nuclear industry itself have resulted in new reactors, such as the European Pressurised Reactor (EPR). These modern reactors are more complicated than their predecessors: better redundancies and greater defence in depth against meltdown, malfunctions, leaks, electrical faults, cracks in containment vessels, improved early warning systems and core catchers. Put another way, there is no regulator anywhere in the world today that would approve the building of a new nuclear plant of the same design as Koeberg. The French CP1 900 PWR series, to which Koeberg belongs, is simply less safe than modern nuclear plants. To be clear, Koeberg is not of the same design as Chernobyl or Fukushima and as such one cannot and should not directly compare the plants. However, this does still mean that a major accident could happen: the causes and chain of events leading up to such an accident would be, due to the design and type of reactor, different at Koeberg. Such a major accident would require the evacuation of people around Koeberg.

Read full Paper on rosalux.co.za.