- INL is Microreactor Central for Testing Designs and Fuels
- Serial Deployment of SMRs Will Bring Down Their Costs
- Newcleo and Denieli to Use Nuclear Energy to Produce “Green Steel”
- Newcleo Plans MOX Fuel Center for Its Advanced Reactor
- Thorizon Secures €20M to Advance Molten Salt Reactor Development
- Rostom has Eight RITM-200 Reactors in Production
INL is Microreactor Central for Testing Designs & Fuels
A scan of multiple announcements by companies developing microreactors, e.g., less than 20 MW of electrical generation capacity, shows that nine of them, so far, have developed or are in the process of developing arrangements with the Idaho National Laboratory (INL) to test their designs and, for some, also the fuels for their reactors.
As the nation’s nuclear energy research laboratory, INL is working with developers, private industry, regulators, to develop, demonstrate, test, and validate a new generation of microreactors so they can be made available to customers.
As part of its research mission, INL is also helping to develop new fuels for microreactor designs. Many of these advanced designs also require higher concentrations of U-235 than the fuel used in the current fleet of operating light water commercial reactors. The new generation of microreactors under development is focused on key design principles which are that they are simple to use, easy to transport and set up, and can go years without having to be refueled.
One of the reasons for the significant interest in microreactors is anticipated lower costs to build and operate them. The costs for these new generation microreactors are still uncertain, although it is anticipated that microreactors can be cost competitive for niche applications such as high-resilience needs, including military applications, remote and geographically difficult locations, e.g., mining and remote communities, and disaster relief. Also, data centers are inking nonbinding MOUs with microreactor developers based on long-term plans to decarbonize the power supplies for their operations.
Competitive Costs of Power from Microreactors
A recent report by the Nuclear Energy Institute: “Cost Competitiveness of Micro-Reactors for Remote Markets,” estimates the cost to generate electricity from the first microreactor will be between $0.14/kWh and $0.41/kWh. In some remote Alaskan areas that are dependent upon diesel generators, electricity prices are more than $1/kWh.
Future costs are estimated to decrease to between $0.09/kWh and $0.33/kWh. Costs are expected to decrease after demonstration, licensing and initial deployment and will depend on the location and type of owner, whether private or public. If one more of these developers can generate enough demand to build their reactors in “fleet mode” via factory production, the costs could come down even further.
Which Microreactors Are Expected to Test Designs and/or Fuels at INL?
A short list, which is incomplete, includes in no particular order, Project Pele, Aalo & MARVEL, eVinci, Radiant, Mobile Nuclear, and Nano Nuclear. Here are snapshots of these projects and their work at the Idaho lab. There are many moving pieces for each of these microreactor developers. This post contains highlights of recent milestones for each of them.
Project Pele: In September 2024 the DOD broke ground on the Project Pele transportable microreactor project at Idaho National Laboratory, which could become one of the first advanced reactors to operate in the United States as early as 2026. DoD is planning to design, build, and demonstrate a transportable high-temperature gas reactor that will operate at the lab’s Critical Infrastructure Test Range Complex.
The reactor will be manufactured by BWX Technologies and connected to INL’s microgrid producing 1 to 5 MW of electrical power.
According to DOD, the prototype reactor facility will be transported in 20-foot shipping containers and tested at the lab. They then plan to transport the reactor module by truck for placement at the complex during the 2026 timeframe to conduct safety reviews and initial planning and testing.
Oklo: In February 2025 Lightbridge Corporation (Nasdaq: LTBR), announced the signing of a Memorandum of Understanding (MOU) with Oklo Inc. (NYSE: OKLO) to conduct a feasibility study for co-locating a Lightbridge Commercial-scale Fuel Fabrication Facility at Oklo’s proposed commercial fuel fabrication facility and to explore opportunities for collaboration in recycling nuclear waste. Oklo plans to license, build, and operate the facility on a site at at the Idaho National Laboratory, located on the Arco desert 25 miles west of Idaho Falls, ID.
In November 2024 Oklo checked off a significant milestone in its path forward toward building a first of a kind micro reactor on a site at the Idaho National Laboratory. This was the environmental review processes of the Department of Energy (DOE) and the Idaho National Laboratory required for construction of the firm’s first micro reactor on the federal site. It is targeting its first deployment at INL in 2027.
Aalo: In December 2024 DOE identified a piece of land at Idaho National Laboratory (INL) as a potential site for Aalo Atomics to build a new experimental reactor facility. The new facility will be used to advance the company’s commercial Aalo-1 microreactor design that the company hopes to deploy before the end of the decade. It plans to submit to the NRC a combined construction and operating license application (COLA) for the project in 2026.
Aalo Atomics is developing a 10 MW sodium-cooled microreactor inspired by DOE’s MARVEL microreactor design which in October 2023 achieved 90 percent final design, a key step that will allow the project to move forward with fabrication and construction.
In May 2024 Aalo announced it had completed its conceptual design of the Aalo-1 – a factory-fabricated 10 MWe sodium-cooled microreactor that uses uranium zirconium hydride (UZrH) fuel elements.
The Austin, Texas-based company is working to optimize the reactor for mass manufacturing and plans to use existing commercial supply chains to deliver clean, low-cost heat to power everything from data centers to industrial facilities.
MARVEL Microreactor: Now in the fabrication stage on the Arco desert 25 miles west of Idaho Falls, ID, MARVEL (short for Microreactor Applications Research Validation and Evaluation) is a distinctive test platform that will aid a rapidly growing nuclear industry as the world searches for dependable low-carbon energy sources. MARVEL will help advanced nuclear developers in several key ways:
- Provide experience with design, start-up, operation and eventual decommissioning of a new reactor, one of the first built at INL in five decades;
- Development and demonstration of key technologies for microreactor development;
- Testing of key operation functions of a microreactor; and
- Enabling nuclear developers to test microreactor applications and access data to refine their designs on the path to commercialization.
eVinci: In September 2024 Westinghouse Electric Company completed the front-end engineering and experiment design (FEEED) phase to test a prototype of its eVinci microreactor at Idaho National Laboratory. The FEEED process is intended to support developers in design and planning for the fabrication, construction, and potential testing of fueled reactor experiments at the DOME test bed operated by the National Reactor Innovation Center (NRIC).
The commercial heat-pipe cooled microreactor is designed to produce 5 MW of electricity on sites as small as two acres of land and will operate for 8 or more years before refueling. The eVinci microreactor is expected to support broad applications ranging from powering remote communities to mining operations and data centers.
Radiant Industries: In November 2024 Radiant Industries completed the front-end engineering and experiment design phase (FEED) to test a prototype of its Kaleidos microreactor at Idaho National Laboratory. The FEEED process supports developers in designing and planning for the fabrication, construction, and potential testing of fueled reactor experiments at the DOME microreactor test bed.
Radiant was competitively selected last year to complete the FEEED process, which includes developing a detailed schedule, budget, design, and test plan for the experiment, as well as a detailed preliminary safety report on its design to ensure safe operations during testing.
The high-temperature gas-cooled reactor (HTGR) is designed to produce 1.2 MW of electricity and operate for 5 or more years before refueling.
The Kaleidos microreactor is expected to support broad applications ranging from replacing diesel generators in remote areas, to providing backup power to hospitals, military installations, and data centers.
MobileNuclear Energy, LLC: In March 2025 MobileNuclear Energy LLC (MNE) announced that it has entered into a Cooperative Research and Development Agreement (CRADA) with Battelle Energy Alliance, LLC (BEA), the operator and manager of the U.S. Department of Energy’s Idaho National Laboratory (INL).
Under this CRADA, INL will support MNE across key aspects of reactor development, demonstration, and deployment. The collaboration will focus on reactor design, testing, safety validation, licensing support, advanced computational modeling, fuel qualification, and commissioning activities. INL’s support will be provided through the National Reactor Innovation Center (NRIC), BEA staff, and other specialized INL facilities.
According to a company supplied list of specifications, the Mobile Power Module (MPM) comes with an integrated turbine-generator produces and 1 MW thermal energy and 350 kW electrical power. Add-on modules integrate with the MPM to provide atmospheric water generation, heating/cooling, hydrogen-based fuel production, EV charging, and other mission-tailored capabilities. MPM and add-on modules are equivalent in size to a 20′ ISO shipping container.
Nano Nuclear: The company has asked the INL to complete reviews of two of its conceptual designs for microreactors. In 2023 a panel of INL scientists and engineers completed a pre-conceptual design review of NANO Nuclear’s “ODIN” low-pressure coolant microreactor design.
In September 2024 Nano Nuclear announced it will collaborate with Idaho National Laboratory to evaluate the heat exchanger design of Zeus, a modular microreactor, through computational modeling and sensitivity analysis via a GAIN Voucher.
GAIN voucher recipients do not receive direct financial awards. Vouchers provide funding to DOE laboratories to help businesses overcome critical technological and commercialization challenges. All awardees are responsible for a minimum 20 percent cost share, which could be an in-kind contribution.
In December 2024 Nano Nuclear signed an MOU with DOE to establish a framework for the collaboration between NANO Nuclear and the DOE to evaluate the feasibility of siting, construction, commissioning, operation and decommissioning of the Company’s ‘ZEUS’ and ‘ODIN’ experimental microreactors at the Idaho National Laboratory (INL).
The company describes its technology offerings in technical development are “ZEUS”, a solid core battery reactor, and “ODIN”, a low-pressure coolant reactor, each representing advanced developments in clean energy solutions that are portable, on-demand capable, advanced nuclear microreactors.
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Serial Deployment of SMRs Will Bring Down Their Costs
- Alphabet, Google’s corporate parent, says the firm’s partnership with Kairos power to build seven advanced reactors to power the search engine’s data center is a key project for the firm.
(NucNet) Google parent company Alphabet is seeking to reduce the cost of constructing new nuclear reactors by deploying a series of small modular reactors (SMRs) through its partnership with developer Kairos Power, according to a recent media statement bt Alphabet’s president and chief investment officer Ruth Porat.
Google and Kairos Power announced a deal in October 2024 that would see the tech company buying power generated by seven reactors to be built by Kairos, a seven-year-old California-based startup.
The agreement targets adding 500 MW of nuclear power starting at the end of the decade, the companies said. The first reactor could be online by 2030 and additional reactors by 2035. The units for Google will include a single 50-MW reactor, with three subsequent power plants that would each have two 75-MW reactors.
Kairos is developing advanced fluoride salt-cooled high-temperature reactor (KP-FHR) technology. Construction of Hermes 1, a pilot 35-MWt version of the KP-HFR, began in July at the Oak Ridge site after a construction permit was issued in December 2023.
In November 2024, Kairos received greenlight from the Nuclear Regulatory Commission to proceed with construction of the two-unit Hermes 2 facility. It will be the first electricity-generating Generation IV plant to be approved in the US and will build on learnings from the Hermes 1 demonstrator.
Alphabet’s Porat was quoted by CNBC as telling the CERAWeek conference in Houston, US, that the public and private sectors should move “as soon as possible” to build a series of new plants that replicate the construction process to drive down costs.
“If we don’t start now in a focused way and replicate a number of them, which is why the Kairos multi tranche is an important kind of proof point, we’re not going to be able to drive down the cost curve,” Porat said.
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Newcleo and Denieli to Use Nuclear Energy to Produce “Green Steel”
- Companies have signed a Memorandum of Understanding to explore the integration of newcleo’s LFR technology with Danieli’s Green Steel Technology and Plants.
- Agreement lays the groundwork to decarbonize steel production through combined electricity and heat from nuclear energy.
Italy’s Danieli & C. Officine Meccaniche S.p.A., a world-leader in iron and steel making plants, and Newcleo SA, the nuclear energy innovator, the nuclear energy innovator, have signed a Memorandum of Understanding (MOU) to explore the integration of newcleo’s Lead-cooled Fast Reactors (LFR) with Danieli’s steelmaking technology to make a further step in combining the production of green steel with nuclear energy production.
By leveraging the distinctive capability of LFRs to provide a combination of electricity and high temperature heat, the companies will focus on developing potential integrated solutions where Newcleo’s innovative LFRs provide both the electricity and high-temperature heat required to feed some of the Danieli Technologies processes for green steel production.
The initiative aligns with the Danieli vision of providing high quality green steel and has the potential to contribute to steelmaking in Europe. The agreement could lead to energy supply solutions across the iron and steel value chain, including in applications linked to the Danieli Digital Melter and possibly the production of Green Hydrogen to power Danieli’s Energiron Direct Reduction Technology to produce metallic iron.
The understanding comes at a defining moment for the European steelmaking and manufacturing industry as demonstrated by the EU Commission’s Strategic Dialogue on the Future of the Steel sector and the Clean Industrial Deal adopted in February, where the EU Commission took bold action to help energy-intensive industries lower their energy costs while also creating markets for low carbon and pledging over €100 billion in support of EU-made clean manufacturing.
The Commission also pledged to accelerate the development and deployment of small modular reactors (SMRs), recognizing their integral contribution to Europe’s competitiveness in global markets and decarbonization strategies.
Recently, the Italian government has taken concrete steps towards the reintroduction of nuclear energy in its energy mix. In this context, these agreements will generate future opportunities for the Italian and European industry to access clean energy at competitive and stable costs over the long term, allowing the continent to deliver on its net zero pledges while maintaining its competitive edge in the global scenario.
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Newcleo Plans MOX Fuel Center for Its Advanced Reactor
(WNN) Reactor developer Newcleo has acquired a site in Chusclan in the Gard department in southern France on which it will build an R&D innovation and training center supporting the development of its future fuel assembly manufacturing facility in France.
Newcleo said the FASTER (Fuel process Assembly Storage Training and Enhanced Reality) center, which will not store or handle any radioactive materials, will play a key role in its strategy to close the nuclear fuel cycle.
FASTER will host: dedicated spaces for testing engineering solutions and maintenance, including office areas; advanced training facilities, featuring rooms equipped for virtual and augmented reality, simulators, and a training workshop with real production equipment; and development and qualification workshops designed to test and optimize manufacturing processes using cutting-edge technologies, such as 3D printing, within a high-tech environment dedicated to innovation and precision engineering. The FASTER centre will be developed in collaboration with leading Italian design company Pininfarina
Newcleo plans to directly invest in a mixed uranium/plutonium oxide (MOX) plant to fuel its small modular lead-cooled fast reactors. In June 2022, the company announced it had contracted France’s Orano for feasibility studies on the establishment of a MOX production plant.
According to Paris-headquartered Newcleo’s delivery roadmap, the first non-nuclear pre-cursor prototype of its reactor is expected to be ready by 2026 in Italy, the first reactor operational in France by the end of 2031, while the final investment decision for the first commercial power plant is expected around 2029.
Newcleo said its first-of-a-kind 30 MWe lead-cooled fast reactor will “serve as an industrial demonstrator, a showcase for Newcleo’s technology, and contribute to the development of the nuclear sector in France”.
Last month, Newcleo announced it had started the land acquisition process for its demonstration LFR-AS-30 small modular reactor in Indre-et-Loire in the Chinon Vienne et Loire community of municipalities in western France.
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Thorizon Secures €20M to Advance Molten Salt Reactor Development
Deep-tech startup Thorizon, pioneering molten salt reactor technology, has secured €20 million in funding to accelerate the development of its advanced small modular reactor, Thorizon One. This includes €16 million as the first tranche of its Series A round, led by the Dutch National Promotional Institution, Invest-NL, backed by an InvestEU guarantee from the European Commission for the research part, with strong backing from Positron Ventures, PDENH, and Impuls Zeeland. All of Thorizon’s existing shareholders have reinforced their commitment in this investment round.
Thorizon recently secured an additional €4 million grant from the Dutch Province of Noord-Brabant in consortium with VDL Groep and Demcon. The recent investments follow an earlier €10 million grant from the France 2030 Innovative Reactor Program of the French government in 2024. In total, including its first equity round, Thorizon has raised €42.5 million to drive the commercialization of its innovative reactor technology.
This funding milestone brings Thorizon halfway to its Series A target, with a focus on attracting European investors to strengthen Europe’s energy security and leadership in nuclear innovation. The capital will drive the prototyping and demonstration of Thorizon One’s groundbreaking “cartridge” fuel system, designed to safely and cost-effectively generate power by recycling nuclear waste. Additionally, Thorizon will finalize the reactor’s basic design, advance licensing, and prototype key components as it progresses toward starting construction in 2030.
With this funding, Thorizon is advancing the development of the Thorizon One, a next-generation reactor that overcomes all traditional reservations against nuclear energy. The Thorizon One is engineered to deliver carbon-free energy while repurposing long-lived nuclear waste as fuel. Its modular design and innovative cartridge-based fuel system provide a scalable pathway to a circular nuclear economy. By harnessing molten salt technology, Thorizon is developing reactors that are inherently safe, cost-efficient, and faster to deploy than conventional nuclear plants—offering a practical solution to Europe’s clean energy transition.
Thorizon has laid a strong foundation for advancing its molten salt reactor technology, securing funding through equity and grants while building a team of 50 engineers across Amsterdam and Lyon. It has forged key partnerships with Orano for fuel development, Tractebel for engineering, and VDL Groep for prototyping, while collaborating with EPZ for early operator input, and with EDF on R&D.
Dutch and French nuclear regulators have initiated a joint preparatory review of the Thorizon One design, and the company is conducting pre-feasibility studies at three nuclear-designated sites in France and the Benelux, targeting construction by 2030.
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Rostom has Eight RITM-200 Reactors in Production
(WNN) Russia’s Rosatom has begun assembling the RITM-200 reactor vessel for the Leningrad nuclear-powered icebreaker, bringing the total number of RITM reactor units currently being produced at its ZIO-Podolsk plant to eight.
The RITM-200 is a pressurized water reactor with a thermal capacity of 175 MW, which converts to 30 MW at the propellers. It is 7.3 meters high with a diameter of 3.3 meters and an integral layout which its manufacturers say means it is lighter, more compact and 25 MW more powerful than previous generations used on nuclear-powered icebreakers. The service life is 40 years.
As of March 2025 there are 8 RITM type reactors are under construction at different stages (for floating power units and for icebreakers). Project 22220 icebreaker each uses 2 of RITM-200 reactors
The new generation of Russian nuclear-powered icebreakers – the Project 22220 vessels – each feature two RITM-200 reactors and the ZIO-Podolsk plant, part of Rosatom’s machine-building division, has already manufactured 10 of them for the icebreakers Arktika, Sibir, Ural, Yakutia and Chukotka.
The RITM-200 reactors, having demonstrated their suitability for Arctic conditions, are also going to be used in floating power plants which are being built to supply electricity for a large industrial consumer in Chukotka. Another project will use the RITM-200N as part of a land-based small modular reactor nuclear power plant in Yakutia. There is also an agreement for six such reactors in Uzbekistan.
The nuclear-powered icerbreakers are a key part of Russia’s plan to develop the Northern Sea Route, the shipping lane along its north coast, which can cut the distance and speed for shipping goods by sea from northern Europe to Asia.
Rosatom’s proposed floating nuclear power plants, with power capacities of 100 MW and 106 MW, have been designed using reactors based on the RITM-200 ones used in the icebreaker fleet. Under a contract signed in 2021, Rosatom’s Machine Engineering Division is supplying four floating power units, each with a capacity of up to 106 MW of electric power, for the Baimsky Mining and Processing Plant. Three of the FPUs will be primary units, while the fourth will serve as a backup and the project is designed to be the first “serial” reference for floating power units and the world’s first experience in electrification using a floating power unit for mineral extraction projects.
The nuclear power plant agreement with Uzbekistan is for a six-unit small modular reactor project featuring the 55 MW RITM-200N, adapted from that used in the icebreakers. The Yakutia plant, which was granted a construction license in April 2023 and which has a commissioning target of 2028, is also due to feature one or two RITM-200N 55 MW reactors, with a service life of 60 years and a five-year refueling schedule. The proposed RITM-400 is an 80 MW pressurized water reactor and is an option for a 320 MW four-SMR plant in Norilsk.
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