The U.S. small modular reactor sector is moving from design toward construction, with several developers advancing through the Nuclear Regulatory Commission's licensing pipeline. TerraPower's Natrium design is the most advanced new build under NRC review, with a construction permit application being actively evaluated for its 345-megawatt demonstration plant in Kemmerer, Wyoming, where site work began in 2024.
NuScale Power remains the only SMR with full NRC design certification, having secured approval for its US460 design built around 77-megawatt modules. Kairos Power received a construction permit for its Hermes test reactor in Oak Ridge, Tennessee, and Oklo obtained NRC approval of the principal design criteria for its Aurora powerhouse, breaking ground at Idaho National Laboratory in September 2025. NANO Nuclear's KRONOS microreactor construction permit application was formally accepted for a proposed deployment at the University of Illinois Urbana-Champaign.
Commercial momentum is building alongside the regulatory progress. NuScale revealed a partnership with ENTRA1 Energy and the Tennessee Valley Authority for a 6-gigawatt SMR deployment program, while Google signed a corporate power purchase agreement with Kairos Power tied to the Hermes 2 project, which aims to supply power to the TVA system by 2030. Analysts expect the first wave of new U.S. SMRs to reach operation in the 2029 to 2032 window.
Source: American Nuclear Society - https://www.ans.org/news/article-6073/nrc-accepts-terrapowers-smr-construction-permit/