Nuclear energy is back on the table in South Africa, but it is not likely to look like the sort of large-scale, conventional plant-build programme that was mooted under the tainted nuclear procurement programme of the Jacob Zuma presidency.
In a media briefing last week, Minister of Energy and Electricity Kgosientsho Ramokgopa stressed that nuclear energy would be a crucial part of South Africa’s energy mix and that activity was under way to re-energise the country’s nuclear capacities.
He was specifically referring to small modular reactors (SMRs), not conventional large reactors like the Koeberg Nuclear Power Station.
Despite concerns about environmental impacts, high initial costs, regulatory hurdles and public scepticism, “what we have accepted is that SMRs are the future”, said Ramokgopa on 20 November.
“There’s about 50 to 60 different SMR technologies that are at different stages of concept. I think it’s only the Chinese that are advanced. We know that we’ve got the capability and in fact, the genesis of the current generation of small modular reactors is the PBMR [pebble bed modular reactor]. We have sunk over 10 billion, 12 billion rands into that programme [and then] abandoned it for reasons that were explained at the time.”
“We think that we need to exploit our skills, exploit the accumulated knowledge with regards to nuclear technology over a period of time and that’s the case we're making to Cabinet,” he said at the time.
According to the International Atomic Energy Agency (IAEA), SMRs refer to small and medium reactors.
“Typically, they are defined as facilities with a power output of up to 700MW. SMRs represent an attractive option for countries with limited financial resources, small electricity grids, or for those which are looking for scalable and flexible nuclear installations,” the agency explains.
(Source: A Vargas / IAEA)
Key to their appeal is their flexibility. The modular aspect of this design allows for additional modules in accordance with demand and is much less location-dependent than hydroelectric or fossil-fuelled power stations or even conventional water-cooled nuclear power stations.
In the South African context, they are appealing for their relatively lower cost, faster deployment and safer designs compared with conventional nuclear power plants.
South Africa’s turn to nuclear
Nuclear energy is getting renewed attention in South Africa as Ramokgopa’s department puts the finishing touches to the soon-to-be-published Integrated Resource Plan 2024 (IRP 2024).
The IRP is South Africa’s roadmap for electricity generation strategy, outlining how the country will meet its energy needs while balancing economic, environmental and social considerations. Nuclear energy, with its ability to generate uninterrupted, greenhouse gas emission-free electricity, is increasingly being looked to complement an increase in variable renewable energy generation.
Read more: ‘Exponential renewables increase’ expected in SA’s revised energy blueprint
South Africa has several favourable factors that would validate the pursuit of new nuclear energy. The fuel used in a nuclear power plant is uranium dioxide and South Africa is one of the top uranium-producing countries in the world. Uranium occurs naturally in the gold-bearing rocks of the Witwatersrand and the copper-bearing ores of the Phalaborwa complex, and is found in relatively smaller concentrations elsewhere in the country.
Important to note, especially as it relates to the country’s interrelated climate action and energy security ambitions, is that 1kg of uranium supplies the same amount of energy as almost three million kilograms of coal.
Burning coal for electricity generation is the single-biggest cause of global warming worldwide and Eskom’s overwhelming dependence on this fossil fuel is largely why South Africa is one of the most carbon-intensive economies in the world per capita with all its attendant deleterious impacts.
Moreover, PBMRs are a specific type of SMR that, at one point, South African experts led the development of globally.
The development of PBMR technology in South Africa began in earnest in the late 1990s. The concept was inspired by earlier designs from Germany, particularly from research conducted at the Jülich Research Center.
According to the IAEA, the PBMR was identified by Eskom as a “leading option” for the installation of new generating capacity. Unlike Koeberg which uses two pressurised water reactors, PBMRs use “inert gases” such as helium to transfer heat away from the reactor core, which enhances efficiency and safety. The PBMR design also has inherent safety mechanisms that reduce reactor power automatically if temperatures rise too high, minimising the risk of overheating or meltdown.
Put differently, a pebble bed modular reactor is “a steel pressure vessel which holds the enriched uranium dioxide fuel encapsulated in graphite spheres. The system is cooled with helium and heat is converted into electricity through a turbine.”
These spherical fuel “pebbles” are machined to a uniform diameter of 60mm, each containing about 9g of uranium. The core of the reactor contains about 360,000 of these fuel spheres and the total uranium in one fuel load is 2.5 metric tonnes. The total mass of a fuel pebble is 210g.
Source: PBMR
In 1999, Eskom established PBMR (Pty) Ltd to advance the technology, with significant investments from various stakeholders including British Nuclear Fuels and Westinghouse. By 2010, the South African government announced it would cease funding for the PBMR project due to a lack of viable customers or investors, leading to significant staff reductions and ultimately halting development efforts.
As a result, by 2010, PBMR Ltd had effectively ceased operations. The project entered a phase of “care and maintenance” to protect its intellectual property, marking a significant setback for South Africa’s ambitions in advanced nuclear technology.
Opportunities for South Africa
Of late, SMRs are receiving much more attention in an increasingly energy-hungry, electrified and climate-conscious world and South Africa has not been blind to these developments. In the middle of November, the Nuclear Energy Corporation of South Africa (Necsa) said that it would sign memorandums of understanding with the China National Nuclear Corporation (CNNC) and Korea Electric Power Corporation (KEPCO).
Necsa told Daily Maverick that “KEPCO collaborations are on project development, construction, operation and maintenance, localisation, state-of-the-art nuclear technology, research and development on new nuclear plant technologies like small modular reactors” and that “a letter of intent signed with CNNC includes forming partnerships in research and development of fuel technologies for nuclear research and power reactors, localisation of some elements of fuel fabrication operations, supply of equipment and services for nuclear power plant and research reactor infrastructure ageing management and capacity building of personnel in the nuclear energy sector”.
At Wednesday’s briefing Ramokgopa said the memorandums were “important in the context of resuscitation of the nuclear programme in the country”.
That resuscitation hasn’t been finalised yet.
In a report tabled before Parliament’s portfolio committee on electricity and energy in September, it was noted that Necsa acknowledged that the transfer of the PBMR from Eskom to Necsa “has not been finalised yet” and that Necsa is “looking forward to resuscitating the technology and taking it forward”.
“Necsa stated that one of their key strategies is positioning itself for energy generation with small modular reactors and the PBMR is one of those. However, according to Necsa, the country has lost some ground with this technology, and it would thus make more sense to identify a partner, to take this technology further – but this partner must not be prescriptive in what the country wants to do,” the report reads.
At the briefing Ramakgopa said: “We know that the Americans are going full steam in relation to SMR technology. We’re beginning to see that a lot of tech companies are investing in companies that are exploring this SMR for purposes of powering their data centres. So that’s the future. So the future is clearly mapped out and the question about the role and place of SMR has been answered.
“So we think that there is vast opportunity."
“We see this not just [as] technology, but we see this as how we can be able to diversify the economy of our country, building on existing and known capabilities of the country.”
Bertha Dlamini, founding president of African Women in Energy and Power, also shared her thoughts with Daily Maverick.
Asked what role she saw SMRs playing in South Africa’s energy mix, particularly in addressing challenges like energy poverty and grid instability, Dlamini explained that as South Africa accelerates the integration of renewable energy sources into its energy system, “it is crucial for Eskom and licensed municipalities responsible for electricity distribution to comprehend the significant role that small modular reactors can play in addressing the intermittency of these sources”.
Read more: SA’s grid transformation — Eskom’s R112bn plan for electricity ‘freeways’ as future generation heads to Cape provinces
“SMRs offer several key advantages in this context: they possess load-following capabilities to compensate for fluctuations in renewable energy output, can be paired with renewables to create efficient hybrid energy systems, contribute to grid stability in the face of increasing electricity demand, aid in decarbonising the energy mix, and provide flexibility in terms of installation locations,” Dlamini said.
“By leveraging these attributes, SMRs can effectively complement renewable energy sources, ensuring a more reliable, stable and sustainable power supply for South Africa’s evolving energy landscape.” DM
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