Ontario Powers Up SMR Future: First Reactor Online in 2029

Ontario is advancing its clean energy goals with the construction of the first of four GE Hitachi BWRX-300 small modular reactors (SMRs) at the Darlington nuclear site. Construction commenced in May 2025, with Unit 1 scheduled to begin producing power in 2029, potentially making it one of the first SMRs to operate in the Western world.

The project benefits from the existing infrastructure and a revitalized supply chain established during the recent C$12.8 billion refurbishment of Darlington's CANDU reactors. This refurbishment, completed ahead of schedule and under budget, has ensured the retention of a skilled nuclear workforce.

More than 100 Ontario companies are slated to supply components and services for the BWRX-300 project. The advantages of building on active nuclear sites include access to established infrastructure, grid connections, and a local talent pool, which can significantly reduce project timelines.

GE Hitachi plans to implement lessons learned from Unit 1 to streamline the construction of the subsequent three units, emphasizing standardized designs for cost optimization. Unit 1 has a price tag of C$7.7 billion, with the full four-unit project estimated at C$20.9 billion, contingent on demonstrated cost reductions typical of SMR rollouts.

The Canadian government's National Electricity Strategy aims to double power generation capacity by 2050, with a target of 10 new large-scale reactors by 2040. Ontario is also exploring a 10 GW nuclear facility at Wesleyville, with reactors potentially coming online by the mid-2040s.

While nuclear development is concentrated in Ontario, interest is growing in other provinces like Saskatchewan and Alberta, with discussions around microreactors in Canada's territories.