The year 2008 is set to be a significant year for the South African nuclear industry. This year will see the optimisation of the South African Nuclear Energy Corporation (Necsa) Safari-1 research reactor, as well as its conversion to use low enriched uranium (LEU) fuel in place of its current highly enriched uranium (HEU) fuel.

In addition, the construction of a second research reactor, Safari-2, will be an option that will be discussed with government. Further, Necsa’s wholly owned subsidiary company, NTP Radioisotopes will be diversifying its activities to include fuel testing for the country’s innovative fourth-generation nuclear power technology, the pebble-bed modular reactor (PBMR), which is cate- gorised as a high-temperature reactor.

PBMR (Pty) Ltd itself hopes that this year will see it secure important regulatory approvals and able to authorise the start of construction of major components for its demonstration power plant. The company is also in negotiations with prospective new shareholders.

Meanwhile, in the course of this year, State-owned electricity utility Eskom hopes to select and sign a letter of intent with a preferred bidder for the construction of a new, third-generation, pressurised water reactor (PWR).

The competitors for the programme to build this new PWR, which will be the country’s first new nuclear power station in more than 20 years, are Areva of France and Westinghouse of the US, part of Japan’s Toshiba group.

This year will also be the first full year of existence for the new Nuclear Industry Association of South Africa (Niasa), established late in 2007.

CONVERSION TO LOW ENRICHED URANIUM
Regarding Safari-1, its current main activity is the production of radioisotopes for nuclear medicine, most notably radiotherapy against cancer.

“At the moment, Safari-1 is running at pretty much full capacity,” explains Necsa CEO Dr Rob Adam. “Some optimisation is possible, in terms of core space allocation, and we have decided to do this. The process should take a matter of months. Optimisation will not involve any extra costs – there are no capital costs involved at all; it just requires computational work and man hours.

“The conversion of the reactor to use LEU instead of HEU should be done by the middle of this year,” he adds. There is a global trend to convert research reactors from HEU to LEU, because the former can be used in the construction of nuclear weapons and the latter cannot.

The HEU used by Safari-1 is 90% enriched, whereas its replacement, LEU, will be 20% enriched. An enrichment of 90% is effectively weapons grade, while an enrichment of 20% is very far from weapons grade (getting from 20% to 90% is neither easy nor cheap).

This will have long-term cost implications for Necsa. At present, it fuels its reactor from its own stockpile of HEU, paid for long ago.

After conversion, it will have to buy LEU on the international market. “This will involve extra costs for us of a couple of million rand a year,” he reveals. “The existing HEU will be used in the production of radio-isotopes, so it won’t be wasted.”

ANOTHER REACTOR?
“However, even with optimisation, if we want NTP to grow, we either have to think of another reactor, or of diversifying into higher-value products,” elucidates Adam. “Concerning another reactor, there are two approaches available – either we use an existing reactor, in another country, which is not fully utilised, or we build a new reactor. We’re looking at both options.”

Necsa does not have the funding to build a new reactor, so the finance would have to come from the State. “We are having discussions with government on this, but they are still in the preliminary stages,” he reports.

A problem is that the advances in nuclear physics are such that reactors are now little needed for pure research, the focus today being on gigantic particle accelerators. On the other hand, a lot of applied research can still be done with research reactors. And then there is their essential role in the production of radioisotopes.

At the moment, these are made using HEU. “LEU can be used to make radioisotopes, but it doesn’t have the efficiencies of HEU,” he points out. “Getting to a situation in which LEU matches the efficiencies of HEU is a ‘Holy Grail’ and an important area of research and development.”

Safari-1 and NTP will continue to produce radioisotopes, but less efficiently. The bulk of the production is of the Molybdenum-99 isotope, which accounts for 66% of NTP’s revenue. “We will still manufacture the same amount of Molybdenum-99, but we also want to grow into other areas, producing other isotopes,” says Adam. “But these alternatives each have much smaller markets – they’re niche products.”

Necsa also cooperates with science council iThemba Laboratories for Accelerator Based Sciences, which also produces isotopes, because reactors and accelerators produce different types of radioisotopes and so the two agencies complement each other.

The possibility of using another country’s reactor involves a different type of product, called p-doped silicon, which is used in the transistor, semiconductor, and microchip industries. Currently, NTP produces some 25 t/y of p-doped silicon with Safari-1, and this accounts for some 20% of its revenue.

P-doped silicon is produced outside the reactor core. A block of silicon is placed in the path of a beam of neutrons produced by the reactor; the silicon absorbs these neutrons, creating heavier isotopes of silicon within the block. These then decay into phosphorus. The result is an accurately known concentration of phosphorus in the silicon, over a uniform gradient.

“It is this that we can do with foreign reactors,” highlights Adam. “We have had some discussions with Egypt in this regard, but they are still preliminary at this stage.”

Egypt has two research reactors, the ET-RR-1 and ET-RR-2, both located in Egypt’s Atomic Energy Authority complex, at Inshas, some 60 km from Cairo. ET-RR-1 is a 2-MW Russian-designed and -built reactor which first entered service in 1961 but which was renovated during the 1980s. The ET-RR-2 is a 22-MW reactor and entered service in the late 1990s; it was designed and built by Argentinian company Invap in a project that also involved the transfer of technology and expertise from Argentina to Egypt.

A new area for Necsa diversification will be opened with the development this year of South Africa’s biosciences strategy.

“We’re looking at the interface between the biosciences and nuclear sciences,” he reports. “We’re working with the Medical Research Council and several universities on this. We have a high-powered team to advise on what products we should diversify into.”

QUO VADIS THE PBMR
This year is also set to be significant for the PBMR, which is so called because of its spherical fuel elements, each some 60 mm in diameter and inevitably nicknamed pebbles, composed of uranium dioxide coated by silicon carbide. “It will certainly be a very impor-tant year in terms of us getting closer to site,” affirms PBMR CEO Jaco Kriek. (The demonstration PBMR will be situated at Koeberg.) The company is advancing on two main fronts: the reactor itself, and the fuel supply for it.

Concerning the reactor, there are two major regulatory approvals which the company is focusing on and hopes to get this year. “The first of these is the construc- tion licence from the National Nuclear Regulator (NNR),” says Kriek. “This involves the submission of a safety analysis report to the NNR, and getting it will allow us to start activities on site. The other major approval we’re going to focus on heavily this year is a favourable record of decision for our environmental-impact assessment (EIA) for the Koeberg site.”

Then there is the manufacture of key components for the reactor. The company needs the prior approval of both Eskom and NNR before it can authorise the suppliers to start production. Both the regulator and the utility need to be assured of the quality and safety of each and every vital component. “We hope to receive approval to start fabrication of the reactor pressure vessel, which will be made in Spain, during the first quarter of this year,” he reports. “It will take three years to fabricate and so, if we start within the next three months, it should be delivered in 2011.”

Similarly, the company hopes to receive, later this year, the authorisation to allow Mitsubishi Heavy Industries (MHI) in Japan to start producing forgings for the turbine casings for the PBMR. MHI has already started making forgings for the reactor core barrel, permission for this having been obtained last year.

“Other key components are the graphite blocks for the reactor core structure,” he points out. “We expect to start baking the graphite blocks within a few months; the machining shop for the PBMR’s graphite has already been commissioned, and this will machine the graphite blocks to the corrrect shapes for the core structure.” All these graphite oper-ations are located in Germany.

Regarding the fuel supply, last year, PBMR received a successful record of decision for its planned fuel plant at Pelindaba. “This year the focus is on finalising the safety case and on winning the other regulatory approvals for the Pelindaba fuel plant.

“Subject to receiving the requisite licence from the NNR, we will commission a commercial coater plant to coat the fuel spheres for the PBMR,” explains Kriek. “The resulting fuel spheres will then be tested in Russia and the Netherlands.”

The coater plant is already functional, but not yet with the LEU that will power the reactor. And before any actual fuel is produced, there will be preliminary tests using depleted uranium.

“We also want to start procurement of components for the fuel plant – this will also be an important focus for this year, but it will be done in close cooperation with the NNR and with all the oversight required from the NNR,” he adds. The company is also hopeful that this year will see the start of a feasibility study for the PBMR in a process heat application for extracting oil from tar sands in Canada.

Concerning possible new shareholders in PBMR, he reveals, “There are formal discussions with two companies, one local, one foreign, about them taking equity stakes in our company, but we don’t expect finalisation this year.” These talks are taking place in parallel, and one of these companies is expected to start a due diligence on PBMR within the next few months. These talks are being handled by the Department of Public Enterprises, as the State is currently the main (but not only) shareholder in the company. “The hope is that both these companies will take equity and give us a complete set of partners,” he avers.

Another major focus for this year is the attraction and retention of skills. “We’re considering setting up a nuclear academy to recruit people into this industry and train them in its requirements,” he states. “The nuclear industry really is different and needs a different mindset.”

ESKOM BANKING ON NUCLEAR
As mentioned earlier, Areva and Westinghouse are in competition to build the new Eskom PWR, in a programme that will cost more than R100-billion. “We are hoping to get the design done some time in 2008,” Eskom nuclear stakeholder management senior manager Tony Stott told Engineering News last year. This will be followed, in 2009, by the submission of an EIA.

“We are going to have to start getting the EIA process and the commercial negotiations running parallel,” he said. “We are hoping to have construction starting at the end of 2010. It’s optimistic, and it’s an ambitious programme, but certainly that is what we would like.” The new PWR would have a capacity of between 3 200 MW and 3 300 MW, and it is expected to take at least six years to build.

Currently, the country’s only nuclear power plant, Koeberg (which has two reactors), has a nominal capacity of 1 930 MW and contri-butes about 5% of the country’s electricity. Koeberg was built by the French. Westinghouse is a shareholder in PBMR.

The new PWR will be only the first in a programme of new nuclear plants, which should include both PBMRs and additional PWRs – Eskom’s aim is to have 20 000 MW of nuclear generating capacity by 2025, which should amount to 30% of the utility’s total generating capacity by that date.

CONSOLIDATING GAINS
“This year will be a consolidation phase for Niasa,” affirms Adam, who is also the chairman of the association’s board.

“We’ve done the set-up stuff, we have a membership list, membership fees and we elected a new board, replacing the interim one.” (One of the new board members is Engineering News columnist Dr Kelvin Kemm.)

“We felt that the nuclear industry was very small in South Africa and a bit fragmented,” explains Kriek (PBMR being a founding member of the association). “We felt that we should get this industry together in terms of skills, creating a platform, instead of different companies trying to speak for the industry.”

The association is intended to improve communications within the industry and to provide an efficient mechanism for the development of a common strategy. “It will be a common platform for the whole industry to engage with stakeholders,

Parliament, and to develop the public’s understanding of the industry,” adds Adam. “Niasa seeks to assist the government in developing its strategy, and to develop the issue of public communications by the industry as a whole.”

“It will communicate for the whole industry, and express the challenges we all face,” agrees Kriek. “Every country with a nuclear industry has such an association.”

BUILDING REGULATORY CAPACITY
“It’s an exciting time to be in the industry,” enthuses Adam.

“There are also big challenges, such as finding, developing, and maintaining skills, and ensuring the capacitation of the National Nuclear Regulator – you can’t build the industry without building the regulator as well. The industry can’t poach people from the regulator.”

“Climate change puts nuclear up there as an important option to supply energy while combatting global warming,” highlights Kriek.

Because of its dependence on coal-fired power stations for electricity, South Africa is one of the world’s worst emitters of carbon.

Last year, Eskom CEO Jacob Maroga admitted that, if Eskom were a country, it would be the twenty-fifth-worst carbon emitting State in the world. “The time is right for nuclear and particularly for the PBMR,” asserts Kriek. “It is not as if energy was still cheap and plentiful.”