The French Liquid-Metal Fast Breeder Reactor Program

Abstract

In any operating nuclear reactor, new fissile isotopes are formed by transmutation of fertile isotopes even as fissile isotopes are consumed. In slow-neutron, or ''thermal'' reactors, which are the backbone of nuclear programs throughout the world today, more fissile isotopes are consumed than are reproduced. The fuel therefore rapidly loses its usefulness and must be removed, even though it contains a substantial portion of untransformed fertile isotopes. Fast-neutron reactors, however, have a neutron balance that is particularly conducive to greater production than consumption of fissile isotopes. This is the so-called ''breeding'' phenomenon. This property, while remarkable, is by no means miraculous. It is simply the consequence of the numerical values of the nuclear properties of heavy nuclides; this has been known since the earliest fission experiments. What gives the breeding phenomenon such appeal today is that the reactors that use it can make a crucial contribution to the problem of world energy supply in the long term. The preceding considerations provide a glimpse of the fast-neutron reactor's attractiveness in long-term energy planning for a country like France, one of the most industrialized countries in the world yet one of the poorest in fossil resources. This theme is developed first bymore » demonstrating that breeder reactors can make an essential contribution to France's energy independence, then by describing the country's technical experience and the industrial organization it has implemented in this area, and finally by discussing the difficulties that remain to be resolved and the future prospects for this type of reactor in France.« less