Selection and evaluation of nuclear fuel cycle strategies. Technical and economic aspects

The original choices of thermal reactors and fuel cycles were largely determined by specific national circumstances and by experience and facilities acquired from defence-related programmes. These led to the development of LWRs in the USA and to the natural uranium/gas/graphite system in the United Kingdom and France, while Canada selected the HWR. Most countries with nuclear power programmes saw the plutonium-fuelled fast reactor, with its breeding potential, as the means to ensure that exhaustion of economic uranium resources would not prematurely curtail the contribution of nuclear power to world energy supplies. Fuel reprocessing was essential to this fuel cycle or indeed to other recycling options to make better use of the available uranium; it was also favoured for waste management reasons. Early expectations of nuclear power growth suggested that a transition from thermal to fast reactors would occur during the present century but the urgency has been reduced by world economic recession, slower increases in nuclear capacity and the continued availability of supplies of low-priced uranium. Reprocessing costs have risen and economics of scale favour large plants, which are therefore most likely to be built in countries with substantial thermal reactor capacities; these countries will be able to provide reprocessing services to others. As the ultimate strategic need for fast reactors has not been reduced by this slowdown it is important to continue the development and demonstration of fast-reactor technology and the associated fuel cycles. Uncertainties in future fuel prices mean that it could be advantageous to introduce fast reactors as soon as they become an economic, although not necessarily the most economic, choice. Notably, fast reactors may be installed initially when and where they become economic compared to coal-fired generation, in order to lay the foundation for more rapid expansion when economic break-even with thermal reactors occurs. (author)