Second Darlington refurbishment begins

"Refurbishing Darlington's Unit 3 is crucial for securing Ontario's long-term energy future," Ontario Minister of Energy, Northern Development and Mines Greg Rickford said. "Today's announcement brings us one step closer to extending the life of Darlington, which will enable Ontarians to benefit from reliable, emission-free and low-cost energy for decades to come."

The start of Darlington 3's refurbishment was scheduled to begin in May but was postponed in response to the COVID-19 pandemic. The unit has now been shut down and disconnected from Ontario's electricity grid, and defuelling - using remote-controlled tooling to remove 6,240 fuel bundles from the unit - will take place over the next three months, after which heavy water will be removed. This will be followed by islanding, a process that will physically isolate the reactor from Darlington's three remaining operating units.

OPG has already completed the refurbishment of Darlington unit 2, which was reconnected to the grid in June. Lessons learned have been incorporated into the plans and preparations for Unit 3 and subsequent unit refurbishments, increasing efficiencies across the project, OPG said.

"Continuous learning is the key to success on any project, especially a mega-project like the Darlington Refurbishment," said Subo Sinnathamby, OPG's senior vice president, nuclear refurbishment. "We have the benefit of having collected more than 4,000 lessons learned during work on Unit 2 and have been applying them to Unit 3 to deliver significantly greater results, including during defuelling."

Darlington generates over 20% of Ontario's electricity. Completion of unit 3's refurbishment is expected in early 2024, with work on unit 1 scheduled to begin in 2022 and unit 4 in 2023. The entire refurbishment project is scheduled for completion by the end of 2026.

At the same time, Bruce Power has begun a project to refurbish and upgrade by 2033 six Candu units at its site in Ontario, extending their operation to 2064.