Ontario announced two Darlington SMR contracts on November 9, 2026, for firms in the province’s east. Gillam Construction Group and Mansteel Rebar will supply building work and steel for the nuclear project, the province said.
The awards cover an office building and steel for plant structures, according to Ontario’s Ministry of Energy and Mines. They are part of construction work, while Ontario Power Generation (OPG) still needs a separate license to operate the first reactor.
What the Darlington SMR contracts cover
The ministry said Carp-based Gillam will receive nearly C$35 million to build the project’s administration building. It put Pembroke-based Mansteel’s award at C$31 million to make, supply and install reinforcing steel for five core buildings.
However, the release contains conflicting figures. A statement from provincial legislator Billy Denault in the same document describes Mansteel’s deal as C$17 million. The release does not explain the difference.
In that release, Mansteel general manager Allen Piddington said the firm already has workers on site. He also said it sources all its reinforcing steel from Canadian steel mills.
What makes a reactor small and modular
Small modular reactors, or SMRs, have up to 300 megawatts of electrical power capacity per unit, the International Atomic Energy Agency says. Builders can assemble their parts in a factory, then ship them to the site. Like other nuclear reactors, they split atoms to produce heat.
Yet smaller does not mean their cost advantage is settled. The agency says each SMR unit needs less money upfront. But it says their ability to compete on cost still needs proof in practice.
OPG plans four BWRX-300 reactors at Darlington, with a combined capacity of 1,200 megawatts. It says the later units need further approvals before construction and operation. The four-unit plan therefore goes beyond the first reactor that OPG is now building.
Construction and operation need separate approvals
Beyond the Darlington SMR contracts, a key step is permission to run the plant. OPG says it applied to the Canadian Nuclear Safety Commission for an operating license in March 2026. That approval would allow it to finish commissioning and run the first reactor after construction.
OPG expects a public hearing on the application, likely in 2027. Its planning goal is to connect the first reactor to the power grid by the end of 2030.
Sources: Ontario, IAEA, OPG project overview, OPG licensing
