Unit 1, the third of four units to be refurbished at Canada’s Darlington Nuclear Generating Station, has completed its overhaul five months ahead of schedule and will soon be reconnected to the grid. The 875 MWe unit 1 at Ontario Power Generation’s (OPG’s) Darlington plant was taken offline for refurbishment in February 2022 after setting a world record by operating for more than 1,000 days straight.
Units 2&3 were successfully refurbished in 2020 and 2023 and work is underway at unit 4, which is currently in the reactor rebuilding phase. Unit 3 returned to service 169 days ahead of schedule. Work is progressing on schedule to be completed by the end of 2026, ending completing the ambitious 10-year, CAD12.8bn ($9.7bn) project.
“With the refurbishment of another unit, OPG, our employees, and our project partners continue to demonstrate that we can execute major nuclear projects not only on time, but ahead of time, and with a clear commitment to quality,” said Ken Hartwick, OPG’s President & CEO. “This latest milestone reflects our decade of preparation and planning, as well as our dedication to quality and innovation, and the hard work of our entire project team, vendors, skilled trades, and energy professionals.”
He added: “As we continue refurbishment of Unit 4, we are committed to keeping up our momentum. With the finish line in sight, we are confident we will be able to deliver this project safely and with quality to support Ontario’s electrifying future.”
Since the project began in 2016, OPG has applied thousands of lessons learned on each subsequent unit to achieve major efficiencies and schedule savings. This includes an industry-first combined pressure tube and calandria tube removal process. Darlington Nuclear provides about 20% of Ontario’s electricity, enough to power more than 2m homes.
According to a report by the Conference Board of Canada, the Darlington refurbishment project and the subsequent 30 years of station operation are expected to generate a total of CAD89.9bn in economic benefits for Ontario and create 14,200 jobs a year.
In addition to producing electricity, unit 1 will be the first Darlington reactor to produce the cobalt-60 isotope (Co-60), which is used to sterilise about 30% of the world’s single-use medical devices, such as syringes, implants, and surgical instruments. About 50% of the world’s Co-60 supply is produced in Ontario’s reactors, including Pickering Nuclear, which has been producing the isotope since 1971.
Since returning to service, Darlington’s overhauled units have established excellent track records, maintaining the station’s reputation as one of the world’s top performing NPPs. After coming back online in 2020, unit 2 achieved a record 529-day continuous run.
OPG is now leveraging its experience on the Darlington Refurbishment to advance North America’s first fleet of commercial small modular reactors at Darlington Nuclear and also continues to plan for the refurbishment of Pickering Nuclear’s units 5-8.
