- Nuclear Energy
- Expert Workshop Series
A critical element of closed nuclear fuel cycles is the fast neutron reactor. Although fast reactor technology has been in existence since the dawn of commercial nuclear power, its deployment has been obstructed by various political, economic, and technical factors. Nevertheless, the theoretical benefits of fast reactors—enhanced passive safety, increased utilization of uranium resources, improved energy security, and dramatic reductions in the volume and radiotoxicity of waste streams—have kept the technology as a potential option for the future of nuclear energy throughout the world. A major point of contention regarding the prospects of fast reactors is the scarcity of uranium resources: while some argue that uranium reserves will remain plentiful for the foreseeable future, others argue that given even modest projections for global nuclear power, the depletion of viable uranium mines is highly likely and thus, more expensive methods of extraction will eventually be necessary. In the latter scenario, a shift to fast reactors and recycling would eliminate the nuclear industry’s dependence on abundant supplies of economically extractable uranium. Other issues that must be considered regarding the deployment of fast reactors are nonproliferation, repository availability, and economic viability. Although the debate persists, given the possible advantages of a fast reactor economy, there is general consensus that R&D into the technology should be continued.
In both the US and the Republic of Korea, the fast reactor has been a point of interest for nuclear R&D projects. Korea’s pyroprocessing-fast reactor fuel cycle R&D efforts have long been underway, particularly as the country faces acute energy security and nuclear waste management issues. Although the once through fuel cycle is currently more viable economically and the potential costs of pyroprocessing and fast reactors remain highly uncertain, approximate evaluations of Korea’s future fuel cycle options generally lead to the conclusion that the critical variable will be the cost of repository space; surging costs of repository storage, a plausible outcome given the Korean government’s difficulties in repository siting, could potentially offset the higher costs of a closed fuel cycle. Within the US Department of Energy, fast reactor R&D has focused on the development of higher strength and more temperature-resistant materials and advanced energy conversion systems, such as the supercritical CO2Brayton Cycle—advances in these areas could significantly lower the costs of fast reactors, thereby facilitating the eventual deployment of this technology. As the US has no definite commitment at present to utilize fast reactor technologies, US fast reactor R&D will likely hinge on international collaborative arrangements and public-private partnerships.