At a glance
Construction on the four-unit Darlington Refurbishment project is now complete.
With construction wrapped up and the last unit expected to return to service in the coming weeks, the overall project is currently four months ahead of schedule and $150 million under budget.
The major project secures over 3,500 megawatts of clean, reliable, affordable energy for Ontario’s growing and electrifying future.
A worker trains on a full-scale reactor mock-up in support of the Darlington Refurbishment project.
After a total of 1,920 fuel channels and 3,840 feeder pipes replaced, and millions of hours worked, it’s official — construction on OPG’s Darlington Refurbishment is now complete and the project is set to be delivered ahead of schedule and under budget.
The company celebrated the major milestone as Darlington Nuclear’s Unit 4 wrapped up its refurbishment in early February. This was the final unit to be refurbished in the four-unit, $12.8-billion mega-project, which kicked off in October 2016 with Unit 2’s refurbishment.
Station staff are now completing final testing ahead of the unit returning to full commercial operation. The overall Darlington Refurbishment project is currently forecast to be completed four months ahead of schedule and $150 million under budget.
“This is a momentous achievement for OPG, Ontario, and Canada,” said Nicolle Butcher, OPG’s President and CEO. “Through this project, we have demonstrated to the world that complex nuclear projects can be completed successfully, ahead of schedule and under budget. Our experience on this refurbishment, and the thousands of lessons we have learned, will serve as our foundation as we advance nuclear’s future. Darlington’s refurbishment has given us the confidence, the tools, and the skills to forge ahead.”
The project’s success reflects a decade of meticulous planning and preparation, all of which took place before any work began. This included the construction of the world’s first full-scale reactor mock-up, which helped train and prepare workers before they stepped into the reactor vault.
The project also benefited from the close collaboration of key project partners, vendors, thousands of skilled trades workers, including Indigenous workers recruited through OPG’s Indigenous Opportunities Network, and efficiencies and lessons learned from each unit overhauled.
Now, with approximately 8,000 lessons learned, OPG will continue to leverage this experience to successfully execute future projects, including the Pickering Nuclear refurbishment, the deployment of four Small Modular Reactors at Darlington, and the proposed large nuclear development in Port Hope.
Learn more about this project and look back at its journey below.
“Through this project, we have demonstrated to the world that complex nuclear projects can be completed successfully, ahead of schedule and under budget.”
-Nicolle Butcher, President and CEO, OPG
Darlington Refurbishment by the numbers
1,920 fuel channels replaced
3,840 feeder pipes replaced
14,200 jobs on average created per year over refurbishment and ongoing operations
$90B in economic benefits for Ontario
96% project spend within Ontario
A look back at a mega-project
The full-scale reactor mock-up at Darlington Nuclear helped train workers to execute the Darlington Refurbishment project.
A row of end covers from Darlington's Unit 2 low pressure turbines are seen lined up on the turbine floor.
Workers train on Darlington's full-scale reactor mock-up.
A new fuel bundle, manufactured at BWXT in Peterborough, is loaded into Unit 3 at Darlington Nuclear.
Workers assemble fuel channels for Darlington's Unit 2.
A male worker in a hard hat and safety glasses prepares to weld a nuclear unit bellows assembly.
A female worker in protective clothing, hard hat, and safety glasses looks ahead while working on OPG's Darlington Refurbishment project.
The Unit 3 generator at the Darlington Nuclear Generating Station.
A low-pressure turbine spindle removed and placed on a stand at Darlington Nuclear.
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