Particle.news
Download on the App Store

Oklo Groves Reactor Reaches First Criticality

Groves’ start-up moves Oklo into hands-on reactor operations and begins a year-long commissioning phase that the company says will underpin isotope sales and larger power projects.

Overview

  • The Groves isotope test reactor reached first criticality on Wednesday, giving Oklo operational data and proving its ability to build and run a low-power reactor from greenfield land to a controlled chain reaction in under a year.
  • Oklo will spend roughly the next 12 months completing hands-on commissioning at Groves while it expects initial isotope sales to begin from its Idaho radiochemistry lab in early 2027.
  • The company closed Q2 with about $3.0 billion in cash and marketable securities, including roughly $1.9 billion raised through at-the-market programs, and raised its 2026 operating cash-use guidance to $120M–$150M and PP&E plans to $400M–$500M to accelerate procurement.
  • Oklo has bolstered its supply chain by acquiring ARMEC and Creative Engineers to internalize reactor components and signed a non-binding LOI with Centrus that could supply HALEU for up to five Aurora units starting in 2029.
  • Oklo says DOE approval of a preliminary safety analysis helps planning for Aurora-INL, but commercial Aurora power deployments still depend on separate NRC licensing, confirmed HALEU deliveries and large-scale project financing with a company target of commercial start in 2028.