Some countries, most notably France, currently use a
closed fuel cycle in which plutonium is separated from the
spent fuel and a mixture of plutonium and uranium oxides is
subsequently burned again. A longer-term option could involve
recycling all the transuranics (plutonium is one example
of a transuranic element), perhaps in a so-called fast reactor.
In this approach, nearly all the very long lived components of
the waste are eliminated, thereby transforming the nuclear
waste debate. Substantial research and development is needed,
however, to work through daunting technical and economic
challenges to making this scheme work.
Recycling waste for reuse in a closed cycle might seem like
a no-brainer: less raw material is used for the same total power
output, and the problem of long-term storage of waste is
alleviated because a smaller amount of radioactive material
must be stored for many thousands of years. Nevertheless, we
believe that an open cycle is to be preferred over the next several
decades. First, the recycled fuel is more expensive than the
original uranium. Second, there appears to be ample uranium
at reasonable cost to sustain the tripling in global nuclear power
generation that we envisage with a once-through fuel cycle
for the entire lifetime of the nuclear fl eet (about 40 to 50 years
for each plant). Third, the environmental benefi t for long-term
waste storage is offset by near-term risks to the environment
from the complex and highly dangerous reprocessing and fuelfabrication
operations. Finally, the reprocessing that occurs in
a closed fuel cycle produces plutonium that can be diverted for
use in nuclear weapons.