NRC Proposes Accelerated Licensing Pathway for DOE and DOW Authorized Reactor Designs
The NRC issued a proposed rule on April 2, 2026, to amend 10 Code of Federal Regulations (CFR) Parts 50 and 53 that would streamline the commercial licensing process for reactor designs that have previously been authorized and tested under prior DOE or DOW programs.[1] The rule builds upon the interagency coordination framework already established by the October 2025 Addendum No. 9 to the DOE-NRC Memorandum of Understanding on Nuclear Energy Innovation[2] and the NRC’s guidance (Guidance) issued on December 8, 2025. The Guidance enables future NRC license applicants to receive licensing efficiency benefits from prior DOE authorizations for certain reactor designs that (1) have been tested and (2) have demonstrated the ability to function safely, in part through voluntary preapplication engagement with NRC staff. The proposed rule, in turn, provides the regulatory pathway through which applicants can formally reference both DOE and DOW authorizations, making the information-sharing and technical coordination contemplated by the Memorandum of Understanding (MoU) directly actionable.
Section 50.43(e) provides two options for license applicants to demonstrate how newer reactor designs accomplish their safety functions. The proposed rule would add a third option, allowing an applicant to reference a prior DOE or DOW authorization and successful testing and demonstration of the authorized design as a means of satisfying NRC requirements. Applicants utilizing this pathway would be required to identify how the attributes of the prior authorization satisfy NRC regulations and address any changes to the design, functionality, associated hazards, siting information, or underlying safety assumptions from those considered in the prior authorization. This amendment would apply across Part 50 and Part 52.
For the Part 53 risk-informed, technology-inclusive framework, the NRC proposes to revise § 53.440(a)(1) to explicitly accommodate the option for applicants to reference a prior DOE or DOW authorization to demonstrate that design features meet the functional design criteria required by §§ 53.410 and 53.420. Applicants would need to identify how aspects of the prior authorization satisfy applicable NRC regulations and consider interdependent effects throughout the commercial nuclear plant and the range of conditions under which design features must function throughout the plant’s lifetime. Publicly available guidance documents will be issued to support implementation of these pathways.
From August to December 2025, the DOE identified four federal sites for rapid AI data center and energy development.[3] For each solicitation, DOE focused on three configurations of project proposals: Integrated Data Center and Energy Projects, Phased Integrated AI Data Center and Energy Projects, and Energy Infrastructure Projects.[4] Each solicitation expresses a preference for innovative energy technology, including nuclear and geothermal technologies, for potential generation sources and requires that new sources be incorporated either directly into the project design or indirectly through a partnership between the AI data center operators and new energy generators.
Siting a nuclear demonstration project at one of these locations provides a “triple win” for FOAK nuclear developers:
The proposed rule’s explicit inclusion of DOW authorizations is a major signal for the microreactor and small modular reactor (SMR) markets. Under Section 91(b) of the Atomic Energy Act, the DOW can authorize reactors for military use outside of the traditional NRC process. Current DOW requests for information (RFI) and solicitations that could serve as the “Reference Design” for future commercial NRC applications include:
For data center developers, the “regulatory sandbox” provided by DOE and DOW land is the most viable path to achieving the 2027-2030 deployment timelines required for next-generation AI clusters. The benefits of the proposed rule include:
By aligning a pilot project with a current DOE or DOW solicitation, developers can essentially “offload” the initial technical and regulatory risk to a federal mission, using the resulting authorized data as a shortcut through the NRC’s Part 50 or Part 53 commercial frameworks.
In March 2026, the DOE successfully demonstrated the use of Gordian AI (built on Microsoft Azure) to convert a DOE safety document into an NRC-ready license application in just 24 hours. This rule makes such AI tools far more effective. Because the rule explicitly allows applicants to “reference” prior authorizations, AI can be used to map the DOE data directly to NRC requirements, reducing the manual “translation” burden that traditionally takes months.
The NRC’s proposed rule represents a significant step toward reducing duplicative regulatory review for reactor designs that have already been tested and authorized by DOE or DOW. By codifying a third pathway for demonstrating safety function compliance, the rule could meaningfully accelerate the commercial deployment of advanced nuclear technologies when both the administration and industry are seeking to expand domestic nuclear energy capacity.
The ultimate impact of the rule, however, will depend on the content and timing of the NRC’s forthcoming guidance documents, the extent to which applicants can demonstrate alignment between prior authorizations and NRC requirements, and any modifications made during the final rulemaking process. The public comment period closes May 4, 2026. This is a critical window for developers to ensure that the forthcoming NRC guidance documents are sufficiently flexible to account for the unique data generated during DOE demonstration phases.
Endnotes
[1] NRC notes that the proposed regulatory text for this limited scope rulemaking would continue to use the title, “Department of Defense,” to avoid creating inconsistencies with or causing confusion in the NRC’s existing regulations.
[2] Addendum No. 9 provides the operational mechanisms for NRC technical staff to observe DOE's authorization reviews and gain firsthand familiarity with the demonstration reactor technologies being tested under DOE jurisdiction. It also establishes processes for sharing documented safety analyses, technical data, and other information generated during DOE's review process so that it can be leveraged in future NRC licensing activities.
[3] Our November 25, 2025, Update delves into all aspects of these solicitations.
[4] In each case, the DOE solicitation states, “The Lease Agreement with the Government is for the purposes of designing, financing, permitting, developing, constructing, installing, owning, maintaining, operating, and decommissioning AI data center and energy generation infrastructure (the Project) including, but not limited to: data center facilities with specialized Information Technology equipment; associated cooling facilities; energy supply infrastructure; transmission and storage infrastructure; and other ancillary facilities and equipment reasonably required for the installation, maintenance, operation, decommissioning, and site restoration/remediation of AI data center and energy generation facilities including such conduits, lines, wiring, electrical systems, interconnection facilities, and other ancillary facilities and equipment reasonably required for the installation, maintenance, operation, decommissioning and site restoration of an energy generation facility given the available real property described herein.”
[5] Air Force SMR RFI (2026): Department of the Air Force, Request for Information: Small/Micro/Modular Reactor Technologies, FA8240-26-R-3001 (Mar. 19, 2026).
[6] Janus Program: U.S. Army & Department of Energy, Announcement of the Janus Program for Commercial Microreactor Deployment (Oct. 14, 2025).
[7] Army announces next steps on Janus Program for next-generation nuclear energy. Nine installations were identified as potential locations for projects, including Fort Benning, Fort Bragg, Fort Campbell, Fort Drum, Fort Hood, Fort Wainwright, Holston Army Ammunition Plant, Joint Base Lewis-McChord, and Redstone Arsenal.
[8] U.S. Dep’t of Energy, Department of Defense Breaks Ground on Project Pele Microreactor (Sept. 24, 2024); Nuclear Reg. Comm’n, Project Pele Overview: Mobile Nuclear Power For Future DoD Needs, INL advances Department of War’s Project Pele demonstration microreactor with first TRISO fuel delivery (Dec. 2, 2025).
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