4 Apr 2025

Canada authorises construction of one BWRX-300 small modular reactor at Darlington

Energy and storage
AI illustration · Illustrative scene, not a photograph of the specific device or experiment.

What was demonstrated

On 4 April 2025 the Canadian Nuclear Safety Commission (CNSC) issued Ontario Power Generation Inc. a power reactor construction licence for one GE Hitachi BWRX-300 at the Darlington New Nuclear Project site in Clarington, Ontario. The licence is valid until 31 March 2035. The CNSC project page describes the BWRX-300 as a 300 MWe, water-cooled, natural circulation small modular reactor, and the project as covering up to four new reactors. This is a licence decision, not an operating result. The sources reviewed report no construction progress and no operating record at the site.

Why it matters

This is a regulatory step, not a demonstration of the reactor running. It shows a national regulator authorising construction of one BWRX-300 at a named Canadian site. The sources reviewed do not say whether the decision will shape how other SMR projects are assessed.

Caveats

  • The licence covers construction of one unit. The project page describes up to four reactors at the site, but the sources reviewed do not say how further units would be licensed.
  • The licence is for construction, so there is no operating record for the BWRX-300 at this site.
  • The news release says the licence carries four facility-specific licence conditions. The sources reviewed do not describe their content. Cost and schedule figures are not given in the sources reviewed.

Technology profiles

Sources

  1. government report
    Commission authorizes Ontario Power Generation Inc. to construct 1 BWRX-300 reactor at the Darlington New Nuclear Project site
    Canadian Nuclear Safety Commission, 4 Apr 2025.
  2. government report
    Darlington New Nuclear Project
    Canadian Nuclear Safety Commission, 25 Aug 2026.

Last reviewed 21 Oct 2026.