PLENTIFUL ENERGY

Figure 1-11. Rendering of the EBR-II Plant and its Fuel Cycle Facility
The downside was the fact that the metal fuel used by EBR-II was not at all
satisfactory. It would not withstand even reasonably lengthy irradiation in the
reactor. A uranium alloy, it swelled substantially under irradiation, and it would
burst its steel cladding if left in the reactor more than a few months. In fact, it was
just this problem that was the pressing reason for providing the reactor with an
onsite processing facility at all. The fact that fuel would have a short life was
accepted and provided for. After its short irradiation time, it was taken out of the
reactor and simply melted. Melting itself partly purified the new fuel. It released the
fission product gases and a chemical reaction with the melt-vessel extracted more of
the fission products, though many were left. It was a crude beginning for
processing, but it did work. Importantly, it introduced the thought that onsite
processing might be simple, feasible and desirable.
Nonetheless, a much longer irradiation life was going to be necessary if there
was to be a successful scale-up to commercial size. This would have been a feature
of EBR-III, the reactor that never was. In the sweeping political changes of the mid
1960s, the most important immediate technical change was to discard metal in favor
of oxide fuel. When problems with metallic fuel burnup became evident in the early
1960s, General Electric led the way in advocating a move to oxide fuel for fast
reactors. The experience with oxide in the thermal reactors that were then starting to
commercialize had been favorable, and it seemed natural to move in that direction.
It was known that oxide would withstand irradiations of considerable length, and, as
a further incentive, the very high melting point was thought to be favorable for
safety.
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