Three nuclear start-ups all focused on lead-cooled fast reactor technologies – France-based newcleo, US-based Oklo and Sweden’s Blykalla – have announced a joint agreement to develop advanced fuel fabrication and manufacturing infrastructure in the United States. Subject to customary approvals, newcleo plans to invest up to $2bn via a newcleo-affiliated investment vehicle. Blykalla, which formed a strategic partnership with Oklo earlier in October, is also considering co-investing in the same projects, and procuring fuel related services from the projects.

The investments aim to span multiple projects under US oversight, foster transatlantic cooperation that enhances energy security, and focus on creating a robust and resilient fuel ecosystem. Specific projects and investment amounts will be detailed in forthcoming definitive agreements.

The partnership includes co-investment into, and co-location of, fuel fabrication facilities and could include repurposing surplus plutonium in a manner consistent with established US safety and security requirements.

“Fissioning surplus plutonium is the best way to eliminate a legacy liability while creating an abundant near-term fuel source. It can accelerate the deployment of multiple gigawatts of advanced reactors and serve as a bridge fuel until uranium enrichment and recycling scale up,” said Jacob DeWitte, co-founder and CEO of Oklo.

“This strategic partnership proves that energy independence relies on advanced fuels and promotes an integrated closed-loop fuel cycle. Newcleo and its partners are ready to add value to the transatlantic cooperation in providing clean, safe and secure energy. The agreement proves that the US and Europe can lead in this sector,” said Stefano Buono, founder and CEO of newcleo.

“By channeling large-scale transatlantic investments into the American advanced nuclear industry, the partnership exemplifies newcleo’s and Blykalla’s interest in the US market and supports the domestic expansion of Oklo’s fuel and fast-reactor technologies. Partnerships like this show how allied collaboration can strengthen energy innovation, leadership, and dominance in the United States,” says the press release announcing the partnership.

“This agreement to implement newcleo’s advanced fuel expertise into Oklo’s powerhouses and invest $2 billion into American infrastructure and advanced fuel solutions is yet another win for President Donald J Trump’s American Energy Dominance Agenda,” said Secretary of the Interior and Chairman of the US National Energy Dominance Council Doug Burgum. “This administration is committed to enhancing energy security, creating more American jobs, and ensuring that the United States remains at the forefront of global energy production and innovation, and I’m honoured to support today’s announcement to advance these goals.”

Oklo is developing fast fission power plants to deliver clean, reliable, and affordable energy at scale, establishing a domestic supply chain for critical radioisotopes, and advancing nuclear fuel recycling to convert nuclear waste into clean energy. Oklo was the first to receive a site use permit from the Department of Energy (DOE) for a commercial advanced fission plant, was awarded fuel from Idaho National Laboratory (INL), and submitted the first custom combined license application for an advanced reactor to the Nuclear Regulatory Commission. Oklo is also developing advanced fuel recycling technologies in collaboration with DOE and National Laboratories.

Newcleo is working to design, build, and operate Gen-IV Advanced Modular Reactors (AMRs) that are cooled by liquid lead and fuelled by reprocessed nuclear waste. With over 100 partnerships and collaborations across the nuclear industry, the growth of the newcleo group is supported through targeted acquisition of key companies.

Blykalla is the Swedish developer of advanced SMRs, commercialising lead-cooled fast reactors for industrial use. The SEALER technology is a compact 55 MWe unit designed to offer a safe, efficient, and scalable power solution.

Oklo says it is on track to bring its first plant online at INL before the end of the decade. Blykalla plans to achieve criticality for its first SEALER reactor by 2030 and begin serial production in the 2030s. According to newcleo’s delivery roadmap, its first lead-cooled fast reactor is expected to be operational in France by the end of 2031.

These targets may prove to be over ambitious. Currently, the only operating liquid metal-cooled fast reactors are in Russia, using sodium as the coolant. Russia is also constructing the world’s first ever lead-cooled SMR (Brest-OD-300). This reactor is based on decades of complex research and development supported by the entire Russian nuclear industry. It is due to begin operation in 2029. By contrast, the fast reactor technologies of Oklo, newcleo and Blykalla are still in the design stage.

Frequently asked questions

  • What are the regulatory and licensing challenges for lead-cooled fast reactors (LCFRs) in the US?

    • The NRC is developing new regulatory frameworks specifically for advanced reactor technologies, including non-light-water reactors (non-LWRs) like lead-cooled fast reactors. In particular, Regulatory Guide 1.232, published in April 2018, offers guidance for non-LWR reactor applicants to align principal design criteria with existing licensing rules. • Further reforms are underway through 10 CFR Part 53, the proposed Risk-Informed, Technology-Inclusive Regulatory Framework for Advanced Reactors. Part 53 aims to provide voluntary, performance-based regulatory pathways for new commercial advanced reactors – including LCFRs – and is expected to be finalised by end of 2027. • Licensing challenges also include proving robust safety in several areas unique to LCFRs: preventing lead solidification, handling lead corrosion in structural materials, mitigating toxicity risks, and designing effective monitoring in an opaque, liquid-metal environment. According to The National Academies’ report, material durability, coolant handling, and environmental regulation (e.g. lead toxicity under EPA rules) are nontrivial hurdles.

  • How will the supply chain for lead, manufacturing, and fuel-fabrication be established or scaled in practice?

    • Sourcing and producing high-integrity structural materials that can resist high-temperature corrosion by lead is essential. LCFRs require specialised steels and alloys; newcleo’s research includes advanced alloys (e.g. Fe-10Cr-4Al-RE) that are being developed to address lead corrosion. • Fuel fabrication: The partnership among newcleo, Oklo, and Blykalla intends to build US-based facilities for advanced fuel fabrication, possibly including MOX or plutonium‐containing fuels under strict oversight. These would need production of components, safety qualification of performance, transport, and secure handling. • Repurposing surplus plutonium: The U.S. has about 52.7 metric tonnes declared excess to military needs; some of this is planned for use as reactor fuel, while some is immobilized. The supply chain would involve converting that material to safe fuel forms (which might include MOX or fast‐reactor‐compatible forms) under rigorous security and regulatory oversight.

  • What are the projected timelines and milestones for each company’s LCFR and fuel infrastructure projects?

    Oklo has a site use permit from the Department of Energy to build its first commercial advanced fission plant (Aurora) at Idaho National Laboratory (INL). It plans the first commercial advanced reactor “before the end of the decade” or by 2030. Blykalla targets first criticality of its SEALER reactor (55 MWe lead-cooled fast reactor) by 2030, with serial production in the 2030s. Meanwhle newcleo aims for its first lead-cooled fast reactor to be operational in France by end of 2031. It is committing up to US$2bn toward fuel‐fabrication and infrastructure in the US, with specifics still being finalised.