# Ontario approves construction of the first of four BWRX-300 small reactors at Darlington

Canonical page: https://technooptimist.io/stories/ontario-approves-construction-of-the-first-of-four-bwrx-300-small-d03a3cbc
Date: 8 May 2025
About: [Ontario Power Generation](https://technooptimist.io/companies/ontario-power-generation.md) · [Darlington New Nuclear Project](https://technooptimist.io/energy/darlington-new-nuclear.md)
Original source: https://world-nuclear-news.org/articles/opg-gets-go-ahead-to-build-first-smr-in-canada

Ontario's government cleared OPG to build the first of four 300 MW BWRX-300 reactors at Darlington, after the nuclear regulator issued a licence to construct in April. The whole four-unit project is budgeted at C$20.9 billion, with the first unit due in service in 2030; it is expected to be the first SMR running in a G7 country.

## Key facts

- Budget C$20.9 billion for four units; first unit C$6.1 billion plus C$1.6 billion of shared systems.
- First unit in service targeted for 2030.
- 80% of spending is meant to go to Ontario companies.

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