Independent nuclear expert Tom Blees, who is president of US-based nongovernmental organisation the Science Council for Global Initiatives, believes that the South African government should leave room in its procurement programme for emerging reactor designs, rather than committing the full 9 600 MW designated for nuclear to established systems.

Blees, who visited South Africa in late October at the invitation of Nuclear Africa, is a strong nuclear advocate, arguing that the technology offers the best chance for meeting the world’s growing energy needs without further accelerating climate change. The transition from fossil-based energy should be accelerated, but he does not believe that renewable-energy systems will ever deliver reliable, cost-effective electricity.

In an interview with Engineering News Online, Blees empathised with South Africa’s reticence in pioneering new reactor designs. However, he said domestic policymakers needed to keep themselves informed about nuclear developments, as there was a strong likelihood of fast reactors and molten-salt systems being commercialised in the coming few years.

South Africa had yet to formally launch its nuclear procurement programme, but has signed intergovernmental agreements with a number of nuclear-vendor countries, the majority of which are expected to offer their latest pressurised water reactor (PWR) designs.

There is still widespread concern about the potential cost of the new nuclear programme and the country’s ability to construct and manage the proposed fleet for some six reactors. South Africa currently has one nuclear power station, the 1 800 MW Koeberg power station, in the Western Cape, which comprises two reactors of the PWR design.

“I would try to not commit to all 9 600 MW from one company, since there are some very promising designs that might be ready in less than five years and could be safer and faster to build, and much less expensive,” Blees said.

“I would strongly urge building the type of reactors that most nuclear physicists and engineers would say we'll be using in the future, which is fast reactors, and more specifically, metal-fueled fast reactors.”

Blees listed several alternatives to the PWR reactors, including Rosatom’s BN system, which is a sodium-cooled fast breeder reactor; and the Economic Simplified Boiling Water Reactor, the Advanced Boiling Water Reactor and the Power Reactor Innovative Small Module (Prism) being promoted by GE Hitachi Nuclear Energy.

Prism, which is the commercial-scale version of the Integral Fast Reactor, developed under the aegis of the US Department of Energy, was the “best reactor that's never been built” and the UK was said to be considering building two such reactors to dispose of their plutonium inventory.

Blees also pointed to strides being made by a company called Thorcon, which plans to use modern shipbuilding techniques to mass-produce modular molten-salt reactor systems.

“So, I would try to avoid committing to starting construction on any nuclear plant beyond 2019 or 2020. Perhaps the most logical approach would be to commit to a small number of plants now and retain an option on future orders, in case none of the new mass-producible designs pan out.”

Therefore, it might be necessary, in the near term, to consider other Generation 3 or 3+ designs that could be built relatively quickly in light of South Africa’s electricity generation shortfalls, particularly to plug the gap that could arise from the mid-2020s, when some coal-fired generation capacity would be retired.

“But reactor choice is a critical decision and will be with South Africa for a century,” Blees said, expressing concern that domestic decision-makers might not be fully aware of some of the options.

He is less bullish, though, on the prospects for fusion, asserting that it’s “an incredibly difficult [technology], and it's useless to consider when planning energy policy”.

“If somebody figures out how to do it for producing commercial power, every country's energy policy will be transformed. But we certainly can't just sit immobile and wait for it,” Blees said, quipping that fusion “is just around the corner, and always will be”.

When deciding on nuclear, South Africa should consider both price and the pace of building the first several plants.

“A component of that would be establishing licensing regulations that will allow for the construction of nuclear plants without interruption once they're started. If such regulations can be established, you should be able to get from breaking ground to power production in about four years or maybe even less.”

It would be “counterproductive and unnecessary” for South Africa to develop its own design certification process, which would add years to the process.

“I believe this is a very important issue to be solved immediately in order to realistically assess the best options and allow for construction to begin as soon as possible.”