Used Fuel
Advanced Fuel-Cycle Technologies Hold Promise for Used Fuel Management Program March 2010 Key Points
The growing need for low-carbon nuclear energy has led to a reassessment of the nation’s long-term used fuel management program, including renewed interest in advanced reprocessing and recycling of used nuclear fuel, advanced fuel fabrication, and development of new reactor designs that could further minimize byproducts of the uranium fuel cycle.
The federal government and industry should pursue research into advanced recycling and reactor technologies as well as development of existing technologies. However, no advanced technology will preclude the need for a federal geologic repository for the ultimate byproducts of recycling used nuclear fuel.
In the interim period, storage of used reactor fuel at volunteer locations would enable safe and secure management of the used fuel until recycling facilities are available.
The expected growth of nuclear energy in the United States and around the world is a key driver behind development of advanced fuel-cycle technologies. Any decision to pursue advanced fuel cycles must consider the economic and nonproliferation factors associated with recycling uranium fuel.
The nuclear energy industry supports continued funding of DOE’s Advanced Fuel Cycle Initiative. The mission of the initiative is to develop fuel-cycle technologies that will meet the need for economic and sustained nuclear energy production while satisfying requirements for a controlled nuclear materials management system.
Industry Supports Integrated Used Fuel Management Strategy The nuclear energy industry supports a three-pronged, integrated used fuel management strategy that includes:
centralized interim storage
research, development, commercial demonstration and deployment of technologies to reprocess and recycle uranium fuel
development of a permanent disposal facility.
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Used fuel storage at nuclear plant sites is safe and secure. However, consolidated interim storage sites at volunteer locations would enable the movement of used fuel from both operating and decommissioned nuclear plants before recycling facilities begin operating. Preferably, interim storage sites would be at locations where nuclear fuel recycling facilities would be developed. The industry supports the development of advanced nuclear fuel cycles, which will take decades to complete. The pursuit of this longer-term objective needs to begin in the near term; however, these activities must not compromise the federal government’s obligation under the Nuclear Waste Policy Act to manage used commercial reactor fuel. At the direction of Congress, DOE pursued development of a permanent disposal facility for used nuclear fuel at Yucca Mountain, Nev. The department applied to the U.S. Nuclear Regulatory Commission in 2008 for a license to build the facility. However, the Obama administration concluded that the Yucca Mountain project is unworkable and should be terminated. In January, DOE announced the formation of a blue ribbon commission to make recommendations concerning the management of used nuclear fuel and highlevel radioactive waste. The commission’s interim report is expected within 18 months and its final report in 24 months. Evaluating Closing the Fuel Cycle for the Long Term The United States, for economic and other reasons, does not recycle used nuclear fuel. Commercial reactor fuel remains in the reactor for three or four years. Under current U.S. policy, that fuel then is to be removed for disposal in a specially designed repository, despite the fact that some 95 percent of usable energy remains in the fuel. However, other nations such as France, Japan and the United Kingdom use a fuel cycle in which used reactor fuel is reprocessed and recycled into new fuel for reactors. Ultimately, the remaining byproducts will be sent to a repository for disposal. Recycling of used fuel has the potential to reduce the need for new uranium supply and enrichment services. It also has the potential to provide greater utilization of a geological repository and lower the risk to the biosphere from the high-level radioactive material stored there. In the United States, reprocessing and recycling would entail the following:
establishing the policy and regulatory requirements for recycling facilities developing advanced used fuel recycling techniques deploying new fuel designs in existing reactors developing advanced reactors to extract additional energy from the recycled fuel and further reduce the volume, heat and radiotoxicity of byproducts in the fuel developing a federal repository.
Development of these new technologies will take time. It is appropriate that the federal government begin to vigorously pursue development of these technologies under programs such as DOE’s Advanced Fuel Cycle Initiative. Advanced fuel-cycle technologies cannot eliminate all of the byproducts in used nuclear fuel. Moreover, the systems eventually developed may not have the capacity to recycle all the commercial used fuel ever generated. The United States still will need a federal repository for disposal of these byproducts and for any unreprocessed used nuclear fuel. Repository disposal also is needed for the high-level radioactive waste created by the federal government from its defense programs. Most of this material is stored temporarily in Idaho, South Carolina and Washington.
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Advanced fuel cycle technologies would capture the unused energy remaining in uranium fuel after a single “once-through” cycle in a reactor and would greatly reduce the volume, heat and toxicity of radioactive byproducts for repository disposal. Since 2006, DOE has been working with volunteer communities studying the possibility of hosting advanced fuel-cycle facilities. DOE in 2008 published a draft environmental impact statement for potential recycling and fast reactor sites. In addition, DOE provided grants to four industrial consortia to propose business plans for the development and commercial demonstration of advanced fuel-cycle facilities. These plans include preliminary designs, costs and financing requirements. Looking to the Future Today’s reprocessing technology—known as PUREX—makes it possible to recycle and reuse the uranium and plutonium from used nuclear fuel. The remaining waste products are mainly unusable fission products, which are mixed with glass for disposal as high-level radioactive waste in a process known as vitrification. The uranium and plutonium separated from used reactor fuel by PUREX reprocessing can be recycled as mixed oxide fuel. France and the United Kingdom use this process in a safe and proliferation-resistant manner. The PUREX process produces plutonium that is stored under strict security and safeguards as provided in internationally agreed protocols. Japan is building a reprocessing facility that uses a modified PUREX process that mixes uranium with the plutonium product. The new facility is scheduled to start operating by the end of 2010. Advanced reprocessing systems do not separate plutonium; rather, they keep uranium, plutonium and other usable elements together, while separating radioactive byproducts that have no energy value. One such process, called UREX+, extracts the fission products from used fuel, leaving the remaining plutonium mixed with uranium and other elements. These uranium isotopes are extracted with the plutonium and recycled as fuel for advanced reactors. UREX+ produces high-level radioactive waste requiring disposal. Although proven in laboratories, UREX+ is not yet commercially proven. The French are developing a process called COEX, which extracts uranium and plutonium together. In the United States, the Department of Energy also is developing other processes, such as “pyroprocessing,” that use metallurgical technology. The private sector is proposing other processes to accomplish the same goal. Finally, a new generation of liquid metal-cooled and fast reactor technologies could provide nuclear fuel cycle services, such as breeding new fuel and consuming recycled nuclear waste as fuel. They could support government-sponsored nonproliferation efforts by consuming material from former nuclear weapons, thus eliminating them as a threat. These reactors are expected to be available after 2020. Conclusion The industry believes that to realize fully the long-term benefits of nuclear energy, the United States and other nations must develop advanced fuel-cycle technologies that will supply recycled fuel when it is appropriate to do so, while reducing the amount of radioactive byproducts requiring disposal in a specially designed repository.
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