Additional SMRs in the pipeline for Darlington

The announcement about three potential additional units builds on January's announcement about a contract to build a single BWRX-300 at OPG's Darlington site. Construction of that unit is scheduled to be completed by late 2028, with the supplying of power to the grid set to start in 2029.

Subject to Ontario Government and Canadian Nuclear Safety Commission (CNSC) regulatory approvals on construction, the additional SMRs could come online between 2034 and 2036.

This timing would allow OPG to apply learnings from the construction of the first unit to deliver cost savings on subsequent units, the government noted. Building multiple units will also allow common infrastructure such as cooling water intake, transmission connection and control room to be utilised by all four units instead of just one, reducing costs even further.

"Once deployed, these four units would produce a total 1200 megawatts of electricity, equivalent to powering 1.2 million homes, helping to meet increasing demand from electrification and fuel the province's strong economic growth," the government said.

"A fleet of SMRs at the Darlington New Nuclear Site is key to meeting growing electricity demands and net-zero goals," said OPG President and CEO Ken Hartwick. "OPG has proven its large nuclear project expertise through the on-time, on budget Darlington Refurbishment project. By taking a similar approach to building a fleet of SMRs, we will deliver cost and schedule savings, and power 1.2 million homes from this site by the mid-2030s."

"OPG and the Province of Ontario have staked a leading position in the deployment of new nuclear with a project that will offer significant energy and economic benefits to Ontario and Canada," said GEH President & CEO Jay Wileman. "As a global clean energy leader, the Province of Ontario is an ideal home for this innovative project. We look forward to working closely with the SMR project partners as we build a fleet of new reactors together and demonstrate nuclear project excellence here in Canada."

On 31 October last year, OPG submitted an application to the CNSC for a licence to construct a BWRX-300 at the Darlington site. This licence is required before any nuclear construction work on the SMR can begin. However, site preparation work is already under way at the site. OPG expects to make a construction decision by the end of 2024.

The BWRX-300 is a 300 MWe water-cooled, natural circulation SMR with passive safety systems that leverages the design and licensing basis of GEH's ESBWR boiling water reactor. The CNSC issued a positive decision in March, making the BWRX-300 the first SMR to complete such a pre-licensing Vendor Design Review in Canada.

The announcement of the additional SMRs comes days after the Ontario government announced it is starting pre-development work to build up to 4800 MWe of new nuclear capacity at Bruce Power's existing site, in what would be Canada's first large-scale nuclear build in more than 30 years.