United States Nuclear Regulatory Commission - Protecting People and the Environment
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Advanced Non-Light Water Reactors and Small Modular Reactors

Reactor designers are developing a number of advanced non light-water reactor (LWR) and light-water small modular reactor (SMR) designs employing innovative solutions to technical nuclear power issues. These designs could be used for generating electricity in isolated areas or producing high-temperature process heat for industrial purposes. In addition, some utilities are considering licensing SMR designs using the 10 CFR Part 52 combined license (COL) or early site permit (ESP) processes. The U.S. Nuclear Regulatory Commission (NRC) expects to receive applications for staff review and approval of SMR-related 10 CFR Part 52 applications over the next few years.

The NRC has developed its current regulations on the basis of experience gained over the past 40 years from the design and operation of large LWR facilities. Now, to facilitate the licensing of new reactor designs that differ from the current generation of large LWR facilities, the NRC staff seeks to resolve key safety and licensing issues and develop a regulatory infrastructure to support licensing review of these unique reactor designs. Toward that end, the staff has identified several potential policy and technical issues associated with licensing SMR and non-LWR designs. The current status of these issues may be found in the series of related Commission documents that span from 2001-2016. Although the more recent Commission documents are focused on SMRs, NRC staff recognizes that many of these issues could apply to advanced non-LWR designs in the future. The staff has assembled a list that describes the most recent SMR and Advanced Non-LWR Technical and Policy Issues, provides an updated status, and links to all pertinent references. The staff has also assembled a list of stakeholder position papers identifying stakeholder documents that communicate opinions to the staff on technical or policy issues. Additionally, the NRC's Office of Nuclear Regulatory Research has engaged in an extensive program focusing on nine key areas of anticipatory and confirmatory research in support of licensing reviews for advanced reactors. The NRC also interacts with its international regulatory counterparts to share information.

Advanced Non-Light Water Reactors

In August 2012, the NRC provided to Congress a requested report addressing advanced reactor licensing. The report addresses the NRC's overall strategy for, and approach to, preparing for the licensing of advanced reactors including advanced non-LWR reactors. The report addresses licensing applications anticipated over the next two decades, as well as potential licensing activity beyond that time. It focuses on the licensing of nuclear reactor facilities for commercial use and illustrates regulatory challenges that may occur if various advanced reactors and advanced non-LWR reactor initiatives evolve into licensing applications.

In 2015, the NRC and the U.S. Department of Energy (DOE) began co-hosting a series of Advanced Non-LWR Workshops. The first workshop was held on September 1-2, 2015 and included presentations and discussions on roles and responsibilities of the NRC and DOE, previous experience licensing non-LWR designs, critical gaps and needs in research and development that need to be addressed, and suggestions for improvements in the licensing of non-LWR designs. The second workshop was held on June 7-8, 2016 and focused on exchanging information from NRC, DOE, industry and included presentations and discussions on strategies for advanced non-LWR reactor development and deployment, recent initiatives; and advanced non-light water reactor fuel development, qualification, and challenges.

Prior to the June workshop, the NRC issued a "Vision and Strategy for Safely Achieving Effective and Efficient Non-Light Water Reactor Mission Readiness." As the NRC prepares to review and regulate a new generation of advanced non-light water reactors, a coherent vision and strategy is needed to assure NRC readiness to efficiently and effectively conduct its mission for these technologies. The vision and strategy described in this report, once executed, will achieve the goal of assuring NRC readiness to effectively and efficiently review and regulate advanced non-LWRs.

The table below provides information on previous and current activities regarding advanced non-LWRs.

Design Application Type Applicant
Next Generation Nuclear Plant (NGNP) Design Certification/
Construction Permit
U.S. Department of Energy, Idaho National Laboratory, NGNP Industry Alliance
Advanced Non-LWR Activities N/A N/A

Small Modular Reactors

The August 2012, Report to Congress also addressed the current and future activities related to SMRs. The report identified SMRs as the technology requiring near term readiness activities.

The NRC has engaged in varying degrees of pre-application activities with several SMR designers over the past several years. The NRC expects to receive a design certification application from NuScale Power, LLC in the second half of 2016.

Below is a summary of the reactor designers and a potential license applicant with whom the NRC has engaged with in pre-application activities.

Design Application Type Applicant
NuScale Design Certification NuScale Power, LLC
BWXT mPower™ Design Certification BWXT mPower, Inc.
SMR-160 Construction Permit/
Operating License
SMR Inventec, LLC, a Holtec International Company
Clinch River Site
Roane County, Tennessee
Early Site Permit Tennessee Valley Authority (TVA)
Page Last Reviewed/Updated Thursday, July 28, 2016