“With Bruce Power’s renewed units 6 and 3 operating with strong performance and unit 4 setting records in its MCR outage, unit 5 was taken off-line for its scheduled outage safely and successfully,” the company said. “This represents the second half of the company’s privately backed MCR Project that will see units 3-8 renewed to provide clean, reliable energy for Ontario’s people, businesses and hospitals for decades to come, while also ensuring a dependable source of cancer-fighting medical isotopes for the world healthcare community.”
Major Component Replacement – or MCR – involves removing and replacing key reactor components including steam generators, pressure tubes, calandria tubes and feeder tubes, adding 30-35 years to the reactor’s operating life. The Bruce programme and ongoing site operations create and sustain 22,000 direct and indirect jobs annually and contribute around CAD4 billion (USD2.9 billion) in annual economic benefits in communities throughout Ontario, the company says.
The company and its partners have leveraged lessons from each MCR and developed state-of-the-art technology, for better performance in each successive outage. Bruce 6 was the first of the six units to undergo the process under Bruce Power’s Life Extension Program, entering its MCR outage in January 2020 and returning to the grid in September 2023 after the completion of its MCR. The next MCR, that of Bruce 3, saw the use of innovative robotics on a nuclear reactor face for the first time: the unit came back online earlier this year, more than seven months ahead of schedule. Unit 4 began its MCR outage in February 2025 and is tracking ahead of the unit 3 MCR.
Bruce unit 7 is scheduled to begin its MCR in 2028, followed by unit 8 in 2030. The province of Ontario is also evaluating a second MCR for units 1 and 2, which were refurbished and returned to service in 2012 after being laid up in the late 1990s.
“Our performance gets better with each MCR outage and we’re committed to delivering these projects safely with high quality and on time to return reliable units to power Ontario forward,” said Bruce Power President and CEO Eric Chassard.
“Ontario’s nuclear advantage is powered by the best workers, engineers and skilled tradespeople in the world and the start of unit 5’s refurbishment is yet another example of nuclear expertise that few jurisdictions can match,” said Stephen Lecce, Ontario Minister of Energy and Mines. “Extending the life of this critical asset will deliver reliable, affordable electricity, while strengthening Ontario’s position as a global energy superpower that can refurbish nuclear plants on time and on budget.”
