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2026 Nuclear Energy Conference & Expo (NECX)
August 24–27, 2026
Dallas, TX|Hilton Anatole
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May 2026
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.
Jack W. Fletcher, Ethan E. Peterson, Jason R. Trelewicz, Lance L. Snead
Fusion Science and Technology | Volume 82 | Number 4 | May 2026 | Pages 901-916
Research Article | doi.org/10.1080/15361055.2025.2514910
Articles are hosted by Taylor and Francis Online.
We present the process and results of neutronics-driven shielding design using metal and ceramic matrix metal hydride neutron shields within the context of compact, high-power tokamaks. In particular, hafnium hydrides were considered within a matrix of stainless steel or magnesium oxide and contrasted with established and novel fast neutron shielding materials. These shielding materials are found to substantially increase the lifetime of toroidal field magnets made of high-temperature superconductors by a factor of up to 14.5. Specifically, a stainless steel–20% HfH1.7 thermal shield and outer neutron shield, paired with an inner tungsten carbide (WC) shield and toroidal field magnet case and winding pack both doped with 40% HfH1.7 by volume, were found to achieve a 93.1% reduction in peak fast neutron flux to high-temperature superconductor tapes. Simultaneously, this configuration reduced the total mass (and cost) of the neutron shield, as well as the nuclear heating rate of the magnet coil, in comparison to monolithic shields of WC and boron carbide.