Unity-2 System Rendering.
Construction of the world’s first fully integrated, commercially relevant fusion fuel cycle – UNITY-2 is underway at Chalk River Laboratories (CRL), led by a joint venture between CNL and Kyoto Fusioneering Ltd (KF). The bright minds behind this industry leading project have joined forces to bring the proof of concept to life, establishing a fully integrated test platform for internal and external partners to see first-hand, validate, stress-test and evolve fit for purpose capabilities of UNITY-2 as a fueling system for fusion deployment globally. Various proponents of the technologies have demonstrated the fusion process in varying degrees of success at the lab scale. With each passing year the numbers are improving, fusion is sustained for longer periods*, the energy produced is closer to a net gain. However, until one key challenge is unlocked, the goal of limitless clean energy remains out of reach. That challenge is the availability of tritium fuel, a key ingredient to a self-sustaining fusion fuel cycle.
| *Fun fact: The longest sustained fusion reaction was achieved by the WEST tokamak in France on February 12, 2025, which maintained a plasma for 1,337 seconds (approximately 22 minutes). |
Today, fusion reaction demonstration units rely on their facilities’ available inventory of tritium fuel, a scarce and limited resource. Once a test facility’s tritium has been used up, which happens quickly when the test loop is in operation, the fusion reaction cannot be maintained. Sustaining fusion beyond a few minutes will require the reactors to produce, or breed, tritium at a rate which is greater than what is used within the reaction itself and ultimately bring that tritium back into the fusion cycle. This is where UNITY-2 comes into the equation.
The global tritium availability in the civilian sector is currently to the order of tens of kilograms (e.g. approximately 30 kg, decaying) with current production only a few kilograms per year. The requirement for a 1,000 MWe (≈1 GW) fusion reactor is typically projected at approximately 50–60 kg of tritium per year. Given this scale gap, relying on the supply chain for provision of this fuel is not an option, hence the importance of breeding and tritium conservation.
The CNL and KF joint venture, Fusion Fuel Cycles Inc. (FFC), is working to demonstrate a continuous fuel cycle loop via the UNITY-2 test facility. In this demonstration, a simulation of deuterium, tritium and helium gases, including selective extraction, recycling and purification of fusion fuel at reactor-like conditions will occur. The test facility will create the conditions for fusion fuel operation, establishing a continuous fuel source that returns the tritium within the test loop, allowing for fusion to be sustained for longer, eliminating the barrier that currently stands in the way of fusion reactors achieving limitless clean energy.
This system is particularly interesting to scientists because it will allow for the injection of different combinations of chemical compositions along with the tritium gas, enabling a wide range of handling technologies to be tweaked while exploring the impact of various contaminants in the process.
“Our facility here at CRL is globally unique,” explains Bryden Klein, the UNITY-2 operations representative and supervisor. “With financial support and by leveraging assets owned by AECL, UNITY-2 will combine unique expertise of both venture partners together into one powerhouse facility. Kyoto Fusioneering brings a distinct distribution in lead-lithium breeding proficiency and CNL offers world-class tritium handling, clean-up, storage, and balancing technology. This is exciting because together as FFC, we will leverage our existing licence and house the largest civilian inventory of tritium in the world. This gives CNL a unique advantage and allows us to manage the materials needed to operate UNITY-2 right here on site.”
Over the last few weeks, FFC has strengthened the future of its capstone project, through a US $20 million, ten-year strategic investment from General Atomics (GA). This long-term commitment will enable FFC to demonstrate the performance of UNITY-2’s critical components and subsystems, accelerating their advancement in technology readiness levels (TRLs) toward commercial deployment. More recently still, FCC secured a CA $20-million loan from the Japan Bank for International Cooperation (JBIC), and Mitsubishi UFJ Financial Group Ltd (MUFG Bank). This loan in addition to the investment from GA will ensure the global fusion industry continues to grow and that tritium fuel cycle technologies can be tested, proven, and deployed at scale in real time.
Contracting and decommissioning teams have been hard at work preparing the site for the transition that will enable FFC to leverage the existing infrastructure. To prepare for this, on-site teams have been facilitating site safe intrusive sampling, planning and retrieval, in collaboration with waste categorization and operations teams.
Decommissioning personnel retrieve samples from a cryogenic system cold box alongside a radiation protection technician monitoring for contamination.
Taking a sneak peek inside, and specifically into the tower, you will find the decommissioning teams collecting samples for contamination analysis prior to the CECEUD’s dismantling and removal. Meanwhile on the outside, trailers are being erected by trade crews as a homebase within the protected side of site for these crews and engineering teams alike to move ahead on the project.
Decommissioning personnel collecting samples from existing systems.
As pre-construction and design planning progress, purchase orders for equipment and fabrication are beginning to come together as part of the larger installation process. The dismantling vendors and fabrication teams, both here at CRL and external partner teams, are preparing for these future steps in the process, including the development of pressure vessels and other common equipment that will be needed to complete the facility.
“The facility licencing aligns with the project scope and will enable us to move the project ahead in real time,” shares Todd Tallon, project supervisor overseeing planning and execution efforts. “We’re thrilled to be trending on-track with the dismantling phase and look forward to skid installations beginning next summer.”
With strategic investment from GA and additional financial commitments secured, FFC has strengthened the funding base for UNITY-2 to the already committed parent funding from CNL/AECL and Kyotofusioneering. As site preparations near completion, the project is transitioning from design into active construction, with work already underway this fall and expected to kick into high gear in late 2025. Commissioning of the UNITY-2 is anticipated in late 2026 with hiring for the project expected to begin shortly after to support commissioning and eventual operational activities in late 2026 and early 2027.
