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2026 Nuclear Energy Conference & Expo (NECX)
August 24–27, 2026
Dallas, TX|Hilton Anatole
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Latest News
Antares achieves zero-power criticality at INL
Leveraging more than $140 million in private capital fundraising, over 322,000 square feet of operational manufacturing space, and multifaceted partnerships with the Departments of Energy and Defense, reactor start-up Antares has become the first company involved in the Reactor Pilot Program to achieve zero-power fueled criticality—a full month ahead of the July 4 deadline set by President Trump’s Executive Order 14301.
This milestone, announced yesterday, was achieved with the company’s Mark-0: a sodium heat-pipe-cooled, TRISO-fueled microreactor. The Mark-0 is a forerunner to the company’s flagship design, which it calls the R1. For Antares, this development represents a key validation of its reactor physics, control systems, and supply chain.
Colin Baus, Hugh Boniface, Ian Castillo, Amir Dashliborun, Christian Day, Takashi Ino, Minoru Jimma, Daiki Kikuchi, Mitch King, Satoshi Konishi, Yoshifumi Kume, Suneui Lee, Nobuo Maki, Yoshinao Matsunaga, John McGrady, Kyosuke Namba, Louis Neumann, Yuhei Nozoe, Richard Pearson, Donald Ryland, Jonas Schwenzer, Stephen Strickwerda, Sam Suppiah, Tim Teichmann, Bibake Uppal, Todd Whitehorne, Tomoya Yokoi
Fusion Science and Technology | Volume 82 | Number 1 | January-February 2026 | Pages 357-372
Research Article | doi.org/10.1080/15361055.2025.2481362
Articles are hosted by Taylor and Francis Online.
UNITY-2 (UNique Integrated Testing facilitY) is a facility designed to replicate the architecture of the deuterium-tritium fuel cycle of a fusion pilot plant (FFP) on a smaller scale. The facility will operate continuously at a steady-state flow rate of 2.3 Pa m3 s−1 using gas puffing, and will allow for the injection of fuel pellets for shorter periods with up to 27.5 Pa m3 s−1. UNITY-2 will demonstrate a fully integrated deuterium-tritium fuel cycle using a license for up to 30 g of tritium at Chalk River Laboratories, therefore reducing the risk of producing a FFP on a decadal timeframe. Its novelty, relative to past and planned fuel cycle experimental demonstrations, lies in the continuous and fully integrated operation, an inner fuel cycle that includes a direct internal recycling loop, an inner and outer loop, and a breeder cycle based on lithium lead coolant. UNITY-2 has a full suite of detritiation systems to demonstrate as low as reasonably achievable releases. Following the successful integrated operation, the technology readiness will reach a maturity to be applied to FFPs.