The partnership is the first international example under the UKAEA’s flagship LIBRTI program
As The Fusion Report covers the maturing of the commercial fusion industry, the growth in the number of cooperative ventures, especially international ones, in the development of fusion systems is very encouraging. An example of this is the United Kingdom Atomic Energy Authority (UKAEA) Lithium Breeding Tritium Innovation (LIBRTI) Program. Yesterday, Commonwealth Fusion Systems (CFS) became the first international partner of the LIBRTI Program to test new tritium blanket technologies for use in its Affordable Robust Compact (ARC) fusion machine, currently under construction in Chesterfield, Virginia. The purpose of the partnership is to verify that tritium production and extraction technologies works in a realistic at-scale engineering mockup. The LIBRTI facility, to be built at UKAEA’s Culham UK campus, will include a neutron source from Shine Technologies, another fusion technology partner. Below is the joint press release from CFS and UKAEA.
CFS Named First International Partner in UKAEA’s LIBRTI Program
Oxford, United Kingdom (July 1, 2026) – The UK Atomic Energy Authority (UKAEA) today announced that Commonwealth Fusion Systems (CFS), the largest fusion energy company, will be the first international company to participate in UKAEA’s flagship Lithium Breeding Tritium Innovation program (LIBRTI).
LIBRTI is a £220 million UK government initiative that aims to demonstrate net tritium production – a vital capability for commercializing fusion energy that means fusion power plants can produce enough of this fuel component to cover their own use.
The program is creating a first-of-a-kind technology facility at UKAEA’s Culham Campus following the recent acquisition of a high-flux neutron source.
In a fusion power plant, a blanket is the region where neutrons from the fusion process strike lithium atoms that then turn into tritium, a form of hydrogen used as fusion fuel. The production technique is called breeding, and the new LIBRTI facility will enable industry partners to develop and verify their blanket technologies in fusion environments representative of full-scale machines.
CFS is a private company based in Devens, Massachusetts, that spun out of the Massachusetts Institute of Technology (MIT) in 2018. The company has raised more than US$3 billion in private capital, making it the best-funded fusion energy company globally. CFS is currently building its SPARC fusion demonstration machine and expects to generate electricity from its first ARC fusion power plant in Virginia in the United States in the early 2030s.
CFS and UKAEA will work together, designing the experimental setup, developing testing protocols, and conducting experiments at the LIBRTI facility. CFS will build the test articles to be used in the first investigations.
Tim Bestwick, CEO, UKAEA, said: “The UK Fusion Strategy emphasises the UK’s position as a leader in fusion research while recognizing the value of continued global collaboration.”
Amanda Quadling, Senior Responsible Officer, LIBRTI, said: “Welcoming CFS is a defining moment for LIBRTI. Their participation adds momentum to our own efforts and accelerates the global pathway to demonstrated fusion powerplant scale technology.”
Brandon Sorbom, Co-founder and Chief Science Officer, CFS, said: “LIBRTI’s specialized testing capabilities will allow us to demonstrate net tritium production and increase confidence in our ARC blanket system design. Through this collaboration, CFS will gain hands-on experience engineering and building blanket systems directly representative of our commercial fusion power plant. We’re thrilled to partner with UKAEA and the LIBRTI team as an early user.”
Heena Mutha, Director of Fuel Cycle and Blanket Technology, CFS, said: “It’s an incredible moment for the fusion industry that we’re building the capability to investigate the performance of blankets in a fusion-relevant environment. We look forward to this collaboration with the UKAEA and LIBRTI.”
Conclusion: Why This Collaboration is Important to Fusion
The game of commercial fusion energy development can be viewed as the pursuit of a number of different approaches all leading to the same result: that being the conversion of fusion fuel (typically deuterium-tritium, or D-T) into energy. While there may be a number of different approaches to fusion, there are also a number of components that are common across the various different approaches; tritium blankets are one of those components. Because of the complexity of fusion machines, teaming with other companies in the fusion industry to develop the required support technologies makes a lot of sense. Expect to hear more announcements of collaborations in this and other relevant areas over the next few months and years as we approach the deployment of working first-of-a-kind fusion machines.
