In the current political and commercial climate electricity companies generally do not like to make a big thing of their involvement with nuclear projects.
Eskom, the South African state-owned power company, and one of the world¹s largest utilities, is however a notable exception. Click on the Eskom website (eskom.co.za) and the first thing that catches your eye is a prominent reference to the pebble bed modular reactor (PBMR) development programme that Eskom is spearheading, and a link to the pebble bed modular reactor¹s own site (pbmr.co.za).
With the signing up of PECO Energy to the programme (see this month¹s news) the current phase of the project is fully funded. PECO is putting up $7.5 million, corresponding to around 10 per cent of the total, while a couple of months ago BNFL put in $16 million, giving it a 20 per cent share. Eskom itself is contributing around 30 per cent, with the South African Industrial Development Corporation and a black empowerment entity taking on the rest of the funding. Compared with the costs of actually building a plant the sums are relatively small. But for a development project these are significant numbers, and suggest a high degree of commitment. The current funding, which would appear to amount to something approaching $80 million or its equivalent, should allow completion of a detailed feasibility study, allowing a firm decision to be made on whether to proceed to a demonstration plant. The current phase of the project, which was given the go ahead by the South African government in April, will also include an environmental impact assessment and what is described as a ³public participation process.²
The shareholders will evaluate the project at various stages and it will also be subject to a series of milestone reviews by the South African government. According to Eskom, preliminary construction activities could ³commence by the second half of 2001², with first criticality about three years later and commercial operation about 2005. This would seem to be an optimistic timetable and the project will do well to survive the process of restructuring now underway in the South African electricity business.
Nevertheless, the Eskom PBMR, which is a high temperature helium-cooled reactor using a direct cycle gas turbine (as described in Modern Power Systems, May 1998), has a number of attractive features that make it well worth pursuing. For one thing Eskom is taking a very hard line on costs. The whole project is driven not by nuclear romanticism but by the need for cost effective electricity generation close to load centres rather than near coal mines, where most of Eskom¹s current generation capacity is located. The low costs derive from, amongst other things, the passive inherent safety achievable in a small high temperature reactor, simplicity, short lead times, modular construction and anticipated serial production. The unit size is very small by nuclear standards, a mere 110 MWe. But the idea is to put several modules together to achieve the required total power – up to ten to give an installed capacity of 1100 MWe, for example. There is no physical process in the reactor that could lead to an event with offsite consequences and the microstructure of the fuel balls themselves constitutes the containment.
Overall the designers of the PBMR are aiming to get away from the expense, complexity and long lead times that have tended to dog nuclear projects. In July, for example, Brazil¹s Angra 2 went critical for the first time. But the original order for this plant was placed as long ago as 1976 and site work has been going on for 20 years. Admittedly there are particular reasons why the project has been delayed, but this kind of thing does not exactly create confidence in potential investors.
If the PBMR proves successful it has the potential to radically alter the way nuclear power is perceived globally. It could turn out to be ³disruptive technology² to use a currently fashionable piece of jargon. And this in turn could have major environmental benefits. It seems undeniable that nuclear power, properly executed, could be very helpful in addressing the issue of climate change – emitting as it does essentially no greenhouse or acid rain gases. No less an environmentalist than James Lovelock, originator of the highly influential Gaia hypothesis, has been a long time and ardent supporter of nuclear energy and reaffirms his views in a new book.* Nevertheless it remains to be seen how much nuclear power will figure, if at all, at the forthcoming COP 6 climate change conference to be held in The Hague (see p9) in November.
A ³positive list² of project types recently proposed by the EU for inclusion under the Clean Development Mechanism emphasises renewables, energy efficiency and demand side management but studiously avoids nuclear projects as these are considered ³controversial² and therefore may not be included in the CDM as currently formulated. France, it so happens, is currently president of the EU. With a more than
75 per cent dependence on nuclear energy, to say nothing of a substantial and order-starved domestic nuclear industry, the French would like to see nuclear power depicted in a more positive light in these
deliberations – as would, presumably, South Africa, with its reawakened interest in nuclear power through
the PBMR
The Eskom PMBR project has been dismissed in some circles as yet another nuclear ³white elephant². But this is far from the case. The pebble bed modular reactor is a technology with tremendous promise whose potential deserves to be fully explored. With funding now in place for the Eskom project this can now be done thoroughly and effectively. The outcome of this process could prove decisive in shaping the future development of nuclear energy.
* Homage to Gaia: Life of an independent scientist, Oxford University Press.