DOE Microreactors Nearing Criticality While NRC Clears the Commercial Path
News Rundown: Summaries for every major nuclear headline
While there aren’t as many reactor design and development headlines to go over, those that we do have for this issue are some of the most significant of this year. Other great headlines are coming from the fuel and supply chain, along with multiple reports of ongoing efforts at the NRC to clear as much debris from the path as possible to fast track the deployment of commercial nuclear plants.
Reactor Design and Development
Nuclear Startup Antares Wins Key Approval Through DOE Program
Antares has achieved the most significant regulatory milestone of a microreactor program to date. They received approval from the DOE for their Documented Safety Analysis (DSA) for their Mark-0 demonstration reactor. This is the first company to receive one of the final approvals prior to reactor startup, making them the most regulatory-advanced project under the DOE’s Reactor Pilot Program.
Antares provided their own version of the flowpath to criticality that can be found in DOE Standard 1271 (DOE STD-1271).
The reactor has been constructed at Idaho National Laboratory and is on schedule to be taken critical by July 4th. The few remaining steps before the reactor startup include a couple additional audits and program evaluations, and the establishment of the Joint Test Group which is a consortium of representatives from the involved parties that will be responsible for overseeing the safe approach to criticality.
Multiple companies are hot on the heels of Antares, with several at the previous step after recently receiving approval for their Preliminary DSAs (PDSA), and some that are sitting on recent NSDAs awaiting return of their PDSA’s. (I spelled “Kaleidos” wrong... sorry, Radiant)
An approved DSA is not achieved until a reactor has been fully constructed and any changes in the reactor design from the previously approved version in the Preliminary DSA (PDSA) have been reviewed and verified for safety. Antares has been in coordination with the government for multiple years and has been one of the leading examples of what is possible when utilizing the alternative licensing pathways outside of the NRC.
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Construction license application submitted for Poland’s first nuclear plant
40,000 pages of technical and environmental factors, quality assurance programs, security classifications, and emergency management systems were submitted to Polish nuclear regulators for the construction of three AP-1000s in Poland. This massive project is years in the making with initial construction activities already underway. Construction is expected to begin in 2028 with the first reactor expected to be operational in 2036.
We have to also point out this wild survey that is cited within the linked article:
“A public opinion poll commissioned by Poland’s Ministry of Energy in late 2025 indicated that support for nuclear energy is strong among Poles. According to the survey, 92 percent of respondents support nuclear power for their nation, and about 80 percent would accept a nuclear power plant near their homes. Only 5 percent oppose nuclear power, and 3 percent are undecided on the issue.“
Buckley SFB, Malmstrom AFB selected for Advanced Nuclear Power for Installations program
Most of our readers have probably long forgotten about this program, so let’s briefly review all the military nuclear efforts that are currently underway:
The Air Force initiative to deploy a microreactor pilot at Eielson Air Force Base in Alaska. This project has some roots all the way back in 2017 and chose Oklo’s Aurora reactor as the vendor. Target for taking the reactor operational is 2028.
Project Pele resides within the Department of Defense’s Strategic Capabilities Office and was started back in 2018. BWXT was chosen as the lead vendor for the design, and the reactor is currently being constructed.
The Advanced Nuclear Power for Installations (ANPI) program under the Defense Innovation Unit (DIU), Army, and Air Force, was announced in 2024 with a vendor selection announced in the summer of 2025.
Eight companies were selected: Antares, BWXT, General Atomics, Kairos, Oklo, Radiant, Westinghouse, and X-energy.
Updates since the program was announced have been relatively scarce. But Radiant and X-energy have announced (link and link) advancements in their agreements with the ANPI program to deploy reactors at various military installations.
The above headline is the only other real announcement we’ve seen with the program, which briefly mentions two of these selected deployment sites, one of them being a Space Force base in Colorado and the other an Air Force base in Montana.
The Air Force has another one-off initiative, this one in coordination with Nano Nuclear at Joint Base Anacostia-Bolling base in Washington, DC. There aren’t any timelines out for this project yet, still in the initial stages.
The last one is Project Janus, which is anticipated to release its initial selection of vendors as early as this month, as alluded to by the project manager in recent interviews. Janus is led by the Army with the intention of developing and iterating microreactor designs for faster commercialization, while the Army also benefits from new resilient power options.
We will also note that there are other initiatives that have yet to fully develop, such as the Navy looking to deploy reactors at naval bases (link).
AMPERA, Scorpio team up for maritime microreactors
AMPERA has partnered with Scorpio to develop maritime applications for their subcritical thorium reactor design. Scorpio brings with them a $10 million investment in AMPERA, along with a wealth of experience in the shipping industry, having a fleet of product tankers under their control. As we’ve mentioned in the past, maritime nuclear outside of the military is likely to face the strongest headwinds in the world of regulations. Host nations may be hesitant to allow nuclear-powered ships that do not operate under strict military programs to dock in their ports without some kind of international agreement.
Looking through AMPERA’s website, the technology seems to be rather novel at almost every single stage:
The TRISO fuel uses thorium instead of uranium
The reactor core is a sphere instead of a cylinder
The neutron flux is externally provided to sustain subcritical operations
And the steam turbine is instead driven by subcritical carbon dioxide
The company states they submitted a letter to the NRC in February detailing their intention to begin the pre-application process.
Fuel, Manufacturing, and Services
Urenco USA Reaches Half-Way Point of Current U.S. Capacity Expansion
We already provided a very thorough breakdown on the nuts and bolts of what some of the verbiage in this explanation means, which can be found here if you’re looking to read up on it. The excerpt of focus is:
The amount of work needed to enrich uranium is measured in SWU. The commercial fleet in the US requires roughly 15 million SWU per year to operate. From the most recent data available, about 3-4 million units of that annual US SWU demand is imported from Russia.
Urenco is halfway through its capacity expansion effort at its uranium enrichment facility in New Mexico. So far, 350,000 SWU of new capacity has been installed over the past year with another 350,000 SWU to go. In this announcement, though, Urenco specified that they intend “to further expand the New Mexico plant’s capacity by up to 2.1 million SWU in the future, based on the needs of its customers and supported by their long-term contracts.”
As they also mentioned in the press release, the driving factor for the expansion is to support the transition away from Russian imports.
EnergySolutions To Be Acquired By Energy Capital Partners (ECP)
Nuclear services firm EnergySolutions is going to be re-acquired by ECP in a transaction scheduled to close later this year. ECP originally purchased EnergySolutions back in 2013 and sold their portion of the company to TriArtisan Capital Advisors in 2022. EnergySolutions is one of the major private nuclear industry companies with work across the nuclear lifecycle, similar to some of the work done by companies like Holtec, Perma-Fix, Amentum, AECOM, and Fluor.
The company coordinates major facility maintenance, modifications, operations, and decommissioning. The company has worked on major projects such as decommissioning the Zion Nuclear Power Station in Illinois, the San Onofre Nuclear Generating Station in California, and the La Crosse plant in Wisconsin.
Project Omega and INL to further investigate UNF recycling with ARPA-E award
Project Omega has received an Advanced Research Projects Agency-Energy (ARPA-E) contract to partner with Idaho National Laboratory on advancing the recycling of used nuclear fuel (UNF). The funding will support kilogram-scale prototype testing of novel inert anodes in a molten salt electrochemical reduction process. The idea is to recover valuable isotopes and actinides for potential use as nuclear batteries or medical applications from UNF while generating engineering data to move toward a pilot-scale processing facility.
UNF consists of the fuel assemblies removed from reactors after they have produced power. The US currently stores tens of thousands of tons of this material at reactor sites with no commercial recycling pathway in place (yet). Project Omega’s nonaqueous method uses electricity in a molten salt bath to break down the fuel electrochemically, avoiding the large volumes of radioactive wastewater created by traditional solvent-based approaches. It also achieves high-purity separations without isolating pure plutonium, which lowers proliferation risks and draws on industrial metal-refining techniques.
Deep Isolation Nuclear Selected for ARPA-E SCALEUP Award to Advance Universal Canister System and Deep Borehole Disposal
Deep Isolation been selected for the DOE’s ARPA-E SCALEUP Ready program, one of only two projects to receive federal backing from a pool of up to $40 million. The other company was Lithios, which will advance a lithium extraction process to produce lithium from low-grade US brine to reduce import reliance.
The award will fund full-scale field testing and regulatory validation of the company’s Universal Canister System at a nonradioactive commercial pilot project in Cameron, Texas. The company is working with some of the biggest names in the industry on the project including Westinghouse, NEC International, Halliburton, Occlusion Nuclear, and Amentum. Westinghouse is taking a leading role in the partnership working with Deep Isolation to secure certification from the NRC to utilize the UCS to transport spent fuel from their eVinci microreactor. This would be on top of the report we shared in our previous rundown detailing the study between Deep Isolation and Oklo for spent fuel from recycling processes.
Zirconium Market Size to Hit USD 4.15 Billion by 2035, Driven by Demand from Ceramics and Nuclear Applications | Report by SNS Insider
The zirconium market is projected to grow from $2.16 billion in 2025 to $4.15 billion by 2035 at a compound annual growth rate of 6.82 percent, according to a new report. While ceramics for tiles and sanitaryware still account for the largest share of demand today, nuclear applications stand out as the fastest-growing segment with an expected CAGR (compound annual growth rate) above 10 percent. This surge stems from the need for zirconium alloy tubing that forms the cladding around uranium fuel pellets inside reactor cores. These tubes must let neutrons flow freely to maintain the fission chain reaction while withstanding extreme heat, pressure, and corrosion from reactor coolant. For anyone new to the topic, zirconium cladding acts like a tough, neutron-transparent shield that keeps radioactive fission products safely contained during decades of power production.
Calvert Cliffs Refueling Outage Delivers Close to $90 Million in Upgrades and Provides Powerful Boost to the Local Economy
This might be the most wholesome press release we have ever read for a nuclear-related industry update. Constellation describes the impact of their routine refueling period for one of the reactors at their Calvert Cliffs plant in Maryland. The press release initially details the $90 million in equipment upgrades, but then spends the majority of the time talking about the positive impact on the local community from the 1,500 workers brought in for about a month to complete the refueling and upkeep period:
Every room at the local hotels are filled
$30,000 raised from the visiting workforce for local charities
Local restaurants extend their hours to enjoy the massive support
Constellation also notes the $21 million in annual property tax contributed to the state by the power plant and the 1.7 gigawatts of electricity provided, which supports over 1.3 million households.
Tennessee Positions Oak Ridge to Lead Nation’s Next Era of Nuclear Energy
Governor Bill Lee announced the state submitted a detailed proposal to the US Department of Energy to host a Nuclear Lifecycle Innovation Campus at Oak Ridge. This initiative would create a dedicated federal site for full-cycle nuclear development, covering everything from fuel production and enrichment to advanced reactor testing and recycling of used fuel. The proposal leans on Oak Ridge National Laboratory and the Y-12 National Security Complex, along with more than 230 nuclear companies in the area, to position Tennessee as the national leader in the next phase of nuclear energy.
Tennessee already stands out with the TVA’s selection for a $400 million federal award to build the nation’s first SMR (a GVH BWRX-300) at the Clinch River site and up to $40 billion in additional funding for manufacturing those units.
Several other states are advancing comparable proposals in direct response to the same DOE request. Nebraska submitted its own bid for a lifecycle campus, Virginia is implementing a five-year strategic plan through its Virginia Innovative Nuclear Hub to drive advanced reactor deployment and workforce development, and Idaho, Utah, and Wyoming are collaborating on regional nuclear hubs with their own campus bids and MOUs.
Policy, Regulation, and Industry
NRC approves Diablo Canyon license renewal, extension
The NRC has approved PG&E’s application to extend the operating licenses for Diablo Canyon’s two pressurized water reactors by 20 years. This clears the federal regulatory hurdle and allows Unit 1 to run until November 2044 and Unit 2 until August 2045, provided the California Legislature approves operations past 2030. Diablo Canyon is the state’s lone operating nuclear facility and supplies about 9 percent of California’s total electricity along with 17 percent of its zero-carbon power, making the decision a direct boost to grid reliability as demand grows and the state pursues its 100-percent clean-energy goal by 2045.
A license renewal is the NRC’s thorough safety and environmental review process that lets a nuclear plant continue running safely beyond its original 40-year license period. The agency examined PG&E’s submissions, consulted other agencies, reviewed public comments, and issued a final Environmental Impact Statement concluding that continued operation would have only a minimal effect. This follows earlier state actions that first kept the plant open through 2030 after it had been slated for closure in 2024 and 2025, underscoring how policy makers now view existing nuclear assets as essential bridges in the clean-energy transition.
NRC Reviews of Reactor Designs Previously Authorized by U.S. Department of Energy or Department of War
The NRC published a proposed rule this week that would allow reactor developers to reference safety authorizations previously granted by the Department of Energy or Department of War for demonstration reactors when applying for commercial NRC licenses. Rather than requiring a complete re-evaluation of designs already tested and proven under government oversight, the NRC would focus its review on any differences or additional risks introduced in the commercial application. This change would amend regulations in existing licensing pathways, creating a new explicit pathway for applicants to demonstrate that their reactor designs can perform required safety functions by pointing back to prior DOE or DOW approvals and test data.
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Terra Innovatum Highlights Accelerating Progress Towards NRC Construction Permit and Expanding Commercial Opportunities in Updated Investor Presentation Ahead of ROTH Conference
The company released a fancy new slideshow presentation for one of their upcoming investor conferences. We’re only looking to highlight the one section related to reactor regulations:
There are two primary pathways for earning a commercial license to operate a nuclear reactor in the United States: Part 50 and Part 52. Just last month, the NRC finally released Part 53, a more technology and size agnostic licensing path, which allows for little to no exceptions to be required to license some of the more advanced reactors in development today.
This slide from Terra’s presentation discusses a fourth licensing path that we might see later this year: Part 57. This pathway appears to be directly tailored to microreactors such as the SOLO reactor being developed by Terra.
NRC Receives Westinghouse Application to Update AP1000 Design Certification
Westinghouse submitted Revision 20 of its AP1000 Design Control Document to the NRC, formally establishing the as-built Vogtle Unit 4 as the standard reference plant for all future deployments. This update incorporates lessons learned from the construction and operation of Vogtle Units 3 and 4. The Design Control Document serves as the comprehensive technical blueprint that outlines every aspect of the reactor’s safety systems, structures, and performance requirements, allowing the NRC to certify the design for licensing new projects. Westinghouse is aligning the certified design with a fully operating unit rather than the original theoretical version.
Separately, the NRC’s recent decision to sunset the Aircraft Impact Assessment rule provides additional opportunity for design optimization in future AP1000 projects.
Introduced after the 9/11 attacks, the requirement mandated evaluations and modifications to protect against a large commercial aircraft strike, which led to reinforced features such as extra shielding in the containment structure. With enforcement of this rule ending, Westinghouse could potentially eliminate or simplify elements added solely for compliance, lowering material use and construction expenses while preserving the reactor’s core safety margins. Combined with the Vogtle-based update, these regulatory shifts position the AP1000 for even faster rollout.
Gov. Sherrill signs bill to end de facto moratorium on new nuclear plants
New Jersey Governor Mikie Sherrill signed legislation that ends a decades-old moratorium on new nuclear power plants in the state by updating permitting rules under the Coastal Area Facility Review Act. The old requirement forced developers to prove they had a permanent federal disposal site for high-level radioactive waste, but no such site exists in the US. It was intentionally worded in a way that made it look like the anti-nuclear activists were still allowing a path for nuclear to be constructed, while they were at the same time blocking the development of any permanent storage facility.
The new law lets projects move forward if they propose a safe, on-site storage or disposal method that meets NRC safety standards. Gov Sherrill announced the change at the Hope Creek Nuclear Generating Station in Salem County and simultaneously launched a state Nuclear Task Force to explore further opportunities.
Existing nuclear plants operated by PSEG already supply about 40% of the state’s in-state electricity generation as New Jersey joins a growing list of states that have recently repealed or loosened similar anti-nuclear policies. Illinois fully repealed its longstanding moratorium in 2025, becoming the first of two states to act this year. California introduced a bill last month to repeal its own 50-year ban, while lawmakers in a handful of other states are actively considering comparable steps.
Something Missing?
Looking for the other major headlines announced this week? Well, they’re probably covered in our other bi-weekly report, the Nuclear Sector Newsletter, that focuses on the publicly-traded side of the nuclear industry. It’s $10/month for coverage of all the public nuclear companies and comes with coverage for quarterly earnings and major announcements. Don’t forget the huge trove of these reports we’ve stacked up for our subscribers to read through as well!
You’ll find all the major announcements from the core nuclear companies: Cameco, BWXT, Mirion Technologies, Graham Corp, Oklo, NuScale, Nano Nuclear, Terra Innovatum, Terrestrial Energy, Hadron Energy, Centrus Energy, Silex Systems, and Lightbridge.
Coverage is also included for all the nuclear-related headlines coming from 30 nuclear-adjacent companies such as Constellation, Vistra, GE Vernova, Rolls-Royce, Curtiss-Wright, Flowserve, Solstice Materials, ASPI, Energy Fuels, Fluor, Amentum, and Fermi.