Aalo Atomics achieves criticality on July 4

July 6, 2026, 3:04PMNuclear News
Aalo Atomics employees during criticality testing. (Image: Aalo Atomics)

Executive Order 14301 set an ambitious goal for at least three test reactors to achieve criticality by July 4. Two private companies participating in the Department of Energy’s Reactor Pilot Program—Antares and Valar Atomics—reached this stage earlier in June, and Deployable Energy—participating in the DOE's Nuclear Energy Launch Pad—became the third last week.

In the last few weeks, reports indicated that Aalo would be next, reaching criticality at Idaho National Laboratory with a low-enriched uranium–fueled, sodium-cooled reactor on or near the target date set forth by President Trump’s EO 14301. In the early hours of July 4, Aalo’s critical test reactor—a full-scale zero-power version of its planned 10-MWe Aalo-X—did just that, becoming the fourth DOE-authorized reactor to hit the milestone.

Profile published on head of MARVEL project at Idaho National Laboratory

May 12, 2022, 7:03AMANS Nuclear Cafe
Idaho National Laboratory nuclear engineer Yasir Arafat (Photo: INL)

From refugee in Bangladesh to top nuclear engineer at Idaho National Laboratory, ANS member Yasir Arafat has led quite an interesting life, as described in a recent online profile written by Donna Kemp Spangler for the INL website. Arafat is leading the development of the Department of Energy’s Microreactor Applications Research Validation and EvaLuation (MARVEL) project at INL. The profile notes that MARVEL, which Arafat envisioned soon after joining INL in 2019, is scheduled to be “built and demonstrated at INL’s Transient Reactor Test Facility and connected to the world’s first nuclear microgrid within two years.”