Record-breaking Unit 1 at Clarington’s Darlington nuclear station back online

The world’s most reliable nuclear reactor is back online after refurbishment, with Unit 1 at the Darlington Nuclear plant re-connected to the grid this week – months ahead of schedule.

Unit 1 is the third of Darlington’s four reactors to be refurbished, part of a $12.8 billion project that is expected to be complete by 2026 when Unit 4 is brought back into service.

The refurbishment project will add another 35 years to the nuclear station’s life.

Darlington 1 was taken offline for inspections and maintenance on February 5, 2021 after a setting a world record 1,106 consecutive days of uninterrupted services, having been online since January 26, 2018.

“The champ is back,” enthused Christopher Adlam, co-founder of Canadians for Nuclear Energy. “The record holder for the longest uninterrupted run of a thermal plant in history … is back from refurbishment and ready to beat its own record!”

Unit 4 refurbishment work this year included completion of calandria tube and pressure tube removal, condenser and moisture separator reheater work, turbine generator controls upgrades, inspection of steam turbine blades and generator stator rewind.

Darlington Unit 2 refurbishment was completed in 2022 and Unit 3 work was finished last year.

Darlington Nuclear Generating Station generates more than over 20 per cent of Ontario’s electricity needs – enough energy to power two million homes.

The new life for the four reactors and the four 300-megawatt small modular reactors set for construction (to be connected to the grid sometime between 2034 and 2036) at the Clarington nuclear plant will serve as a catalyst for the next zero-emission economy.