Construction of Four Small Modular Reactors at Darlington will amount to an estimated cost of $21 billion.
Construction on the first of four Small Modular Reactors (SMRs) at Ontario Power Generation's (OPG) Darlington Nuclear Generating Station, located east of Toronto, is expected to begin by the end of 2025. This marks a significant milestone for Ontario as it becomes North America's pioneering SMR construction site.
The initial reactor at the Darlington site should be up and running by the end of 2029, according to energy officials. The Canadian Nuclear Safety Commission (CNSC) has given the green light for OPG to build up to four General Electric Hitachi BWRX-300 SMRs at the site, with a combined capacity of up to 4,800 MW for the Ontario electricity grid.
The first reactor is anticipated to produce power for approximately 1.2 million homes, generating 1,200 megawatts of power. The project is expected to create 18,000 jobs, including 3,700 highly skilled positions, primarily for Ontario-based companies.
These companies will benefit from 80% of the spending on the entire project, as they provide the skilled workers needed to build the new reactors. Once built, the SMRs are projected to operate for 65 years.
With Ontario's increasing electricity demand expected to grow by 75% by 2050, this project is a significant step in the province's push to rely more heavily on nuclear generation to meet its energy needs.
The DNNP is just one component of a larger push from Energy Minister Stephen Lecce to expand nuclear capacity. This plan includes exploring a new, large-scale plant at Bruce Power, considering a new nuclear plant near Port Hope, and refurbishing units at the Pickering nuclear plant to extend its lifespan.
Lecce is also bullish on exporting Ontario's nuclear know-how abroad, with the province having signed agreements worth over $1 billion with companies in Estonia, Poland, and the Czech Republic. These agreements will see Canadian companies and workers build and operate reactors overseas.
This report by The Canadian Press was first published May 8, 2025.
Allison Jones and Liam Casey, The Canadian Press
[1] Darlington New Nuclear Project. (n.d.). Canadian Nuclear Safety Commission. https://nuclearsafety.gc.ca/eng/resources/communications/proposed-projects/darlington-new-nuclear-project[2] Ontario Power Generation. (n.d.). Darlington. https://www.opg.com/our-business/generation/nuclear/darlington[3] Darlington Nuclear Generating Station. (n.d.). Nuclear Energy Institute. https://www.nei.org/resources-media/fact-sheet/darlington-nuclear-generating-station[4] Small Modular Reactors (SMRs). NEI Nuclear Energy Institute. https://www.nei.org/resources-media/fact-sheet/small-modular-reactors-smrs
By 2029, Ontario is projected to export its nuclear technology know-how, thanks to the successful completion of the first Small Modular Reactor (SMR) at Ontario Power Generation's (OPG) Darlington Nuclear Generating Station. The initial reactor at the Darlington site, up and running by this date, will have a capacity of 1,200 megawatts, capable of powering approximately 1.2 million homes. The Ontario government's push to increase nuclear capacity also includes plans to construct more reactors at Bruce Power, explore a new plant near Port Hope, and refurbish units at the Pickering nuclear plant.
