The Nuclear Regulatory Commission (NRC) has formally begun its review of the construction permit application for an advanced microreactor at the University of Illinois Urbana-Champaign. 

The announcement marks the transition from the agency’s acceptance review to the substantive technical evaluation of NANO Nuclear’s KRONOS design.

This step carries more weight than the initial filing. Submitting an application demonstrates readiness on paper; the NRC’s decision to open a full review confirms the submission meets the threshold for detailed scrutiny. 

For a first-of-a-kind microreactor project, clearing that gate is a concrete regulatory advance.

We've tracked the Illinois project closely, including the construction permit application submission itself, described at the time as a defining moment for commercial microreactor deployment. Earlier coverage in October 2025 detailed the start of drilling and site preparation work with the university. 

We've also detailed other updates from the company including their recent MOU with Supermicro and progress with their high-assay low enriched uranium (HALEU) transportation package.

The KRONOS effort is also not occurring in isolation. Other advanced reactor programs have recorded measurable NRC milestones in recent months with TerraPower’s Natrium reactor in Wyoming receiving its construction permit and X-energy achieving a notable environmental clearance for its four-unit Xe-100 project at Dow’s Seadrift site in Texas.