The FuTure oF nuclear Fuel cycle - MIT Energy Initiative

Appendix E — Status of Fuel Cycle
Technologies
The existing fuel cycle technology reflects historical fuel cycle goals and the technology
available at the time. From the 1960s through the early 70’s, the expectations for nuclear
power growth were high and uranium resources were thought to be extremely limited
which resulted in (1) the assumption that the LWR technology was a transition technology
because of inefficient use of uranium, (2) LWR SNF would be reprocessed and recycled
back into LWRs for a limited time, and (3) there would be a rapid transition to a closed fuel
cycle where all SNF would be reprocessed and recycled into high-conversion-ratio sodiumcooled
fast reactors. LWR SNF pools at reactor sites were designed to store inventories of
SNF for a few years before being sent to reprocessing facilities to recovery the fissile materials
for reuse. Later in the decade, concerns regarding proliferation surfaced during the
Ford/Carter era that resulted in a policy decision not to process SNF for recycle of plutonium,
causing the abandonment of the Barnwell reprocessing plant for recovery of plutonium
from LWR SNF. This decision was reinforced by economic factors (better LWR fuels, low
uranium prices, higher-than-expected costs of SNF recycle, and high cost of fast reactors)
that made once-through LWR fuel cycles more attractive. The LWR became the preferred
reactor in most of the world. Slow growth in nuclear power stopped RD&D on fast reactors
in the United States. The once-through LWR fuel cycle evolved as the U.S. reference fuel
cycle technology.
onCe-throuGh Fuel CyCle teChnoloGy
The historical goals for improved once-through LWR fuel cycles have been driven by either
improving short-term economics or nonproliferation characteristics of the fuel. The
last major program was in the 1970s to increase the burnup of LWR fuel that improved
economics (lower fuel fabrication costs, less frequent refueling of reactors, and less SNF for
disposal) and improved nonproliferation characteristics (higher radiation levels associated
with SNF and less plutonium per unit of energy produced). There has been limited work
on more advanced LWR fuels (SiC clad, new fuel matrix materials) that could have major
benefits in terms of reactor safety (larger safety margins) and waste management (better
waste form)—but not the sustained effort required to commercialize a new fuel. There are
several recent developments.
p High-temperature reactor fuel. In the last several years a reliable high-temperature reactor
fuel has been developed—a major step toward developing a commercial high-temperature
reactor that most likely will operate on a once-through fuel cycle.
appendix e: Status of Fuel cycle Technologies 229