Ontario greenlights construction of Canada's first small modular reactor

Mike Crawley · CBC News

· Posted: May 08, 2025 9:00 AM EDT | Last Updated: 7 minutes ago

Premier Doug Ford's government has given Ontario Power Generation the green light to start construction on Canada's first small modular reactor, a new nuclear energy technology to be built next door to the Darlington power plant. 

The small modular reactor (SMR) would provide 300 megawatts of power, enough electricity to supply about 300,000 homes, at an estimated construction cost of $7.7 billion, according to briefing documents from Ontario's Ministry of Energy and Mines. 

It would be the first of four such reactors that OPG aims to build on the site, at a total project cost of $20.9 billion, in an effort to meet what's forecast to be a steep rise in demand for electricity in the province.

Ontario's Minister of Energy and Mines, Stephen Lecce, made the announcement Thursday near the Darlington nuclear generating station. Preparation work has already begun at the project site, immediately east of the existing nuclear plant along the Lake Ontario shoreline. 

In a briefing, ministry officials told reporters that roughly 80 per cent of the SMR project spending will go to Ontario companies, another 15 per cent to European and Asian firms, and just five per cent to companies in the U.S., primarily for GE Hitachi's design and development of the power plant model, called the BWRX-300. 

Ontario would become the first place in the world to build the BWRX-300, which is a smaller version of GE Hitachi's existing boiling water reactor technology. 

The officials say the Canadian companies involved in the project will have the potential to export components to other countries that decide to build this type of SMR. 

The timeline is to finish construction of the first reactor by the end of 2029, and connect it to the grid in 2030. 

In April, the Canadian Nuclear Safety Commission issued its approval for construction to begin. 

The average lifetime cost of electricity generated by the SMRs is estimated to be 14.9 cents per kilowatt hour (kWh), according to an analysis by the Independent Electricity System Operator, the provincial agency that oversees the provincial grid. 

According to that analysis, providing a similar level of base power as the SMRs by building wind and solar power with battery energy storage would cost in the range of 13.5 to 18.4 cents per kWh. However, that alternative would require additional transmission, use up far more land and potentially face constraints in finding acceptable sites. 

While the provincial government has approved the project, there's no taxpayer money allotted to build it. OPG will finance the construction cost through a combination of cash on hand and taking on debt, recovering the cost over the lifetime of the project by charging ratepayers for electricity. 

However, the Ford government spends billions of dollars in taxpayer funds every year to subsidize electricity rates. 

The government budgeted $7.3 billion for those hydro subsidies last year, more than four times what Kathleen Wynne's Liberal government earmarked back in 2018. The 2025-26 budget is set to be tabled next Thursday. 

Officials say the SMR project at Darlington will create and sustain 3,700 jobs per year over the next 65 years and generate $13 billion (in today's dollars) of municipal, provincial and federal tax revenue over that same period.