South Africa perfects pocket reactor

Michael Dynes

A scaled down reactor developed in South Africa could open the door for a new export market for safer PBMR technology

South Africa renounced its nuclear military programme in the run-up to black majority rule in 1994. It did not, however, renounce the nuclear technology that it had laboured on for years to perfect.

Instead, its legions of scientists and technical experts were quietly redeployed to a civilian nuclear programme, known as the pebble bed modular reactor (PBMR), which it has been working on ever since, and which is shortly expected to begin bearing fruit.

Taking a German design from the 1950s, which uses nuclear fuel spheres (pebbles) rather than rods, and is cooled with helium gas rather than water, the PBMR is widely regarded as inherently safer than conventional pressurised water reactors (PWRs) as it is fuelled continuously, eliminating the need for refuelling shutdowns.

South Africa's PBMR, known as a pocket reactor because it can fit into a three story building, is approaching the end of its design phase, and the first pilot project is due to be constructed near Cape Town, alongside the existing Koeberg nuclear power plant, around 2012.

Each reactor would be capable of generating around 165 mega watts (MW), and as many as ten reactors can be linked together, sharing a common control unit, enabling each power plant to generate up to 1,650 MW - enough to provide sufficient electricity to power an average-sized town.

The South African government has ploughed more than $700 million into the scheme in the expectation that the project would help meet the country's burgeoning demand for electricity, and provide a potentially lucrative export market for South African designed and built power stations. That was before mounting concerns about climate change put a huge premium on the generation of carbon-free electricity.

Now that the pocket nuclear reactor is approaching commercialisation, countries from both the developed and developing world are queuing up to express interest in acquiring South Africa's home grown nuclear technology. The US, Russia, China, India, Singapore, Algeria, and scores of power hungry developing countries, are monitoring the project's progress closely.

In March this year China, which has its own PBMR programme, signed a cooperation agreement with South Africa, in which both parties have agreed to "cooperate in areas of common interest". Stripped of the diplomatic jargon that invariably hides the real meaning of such agreements, China and South Africa can be expected to exchange the scientific know-how needed to help accelerate commercial rollout of PBMR technology, backed up with Chinese cash.

Interest in PBMR designs is likely to increase substantially in the years ahead as pressure mounts on both developed and developing countries to reduce their greenhouse gas emissions, forcing them to look to nuclear power as a commercially viable alternative to coal and oil as a provider of baseload generating capacity.

With the Three Mile Island/Chernobyl-era of stagnation in the nuclear power industry rapidly coming to an end, South Africa is positioning itself to capitalise on the opportunities presented by the revival of the nuclear power industry throughout the world. Soon it may not only be South African coal which keeps the lights burning, but South African power stations too.