Bruce Power has reached the major milestone of "substantial completion" of the construction phase of Major Component Replacement portion of refurbishment of Bruce unit 6 and will now begin refuelling work as the focus moves on to returning the plant to service later this year.

Bruce 6's turbines should be spinning again by the end of the year (Image: Bruce Power)

Unit 6 is the first of six Candu reactors at the site in Ontario to undergo refurbishment in a privately funded investment that will extend the life of the site through 2064. The unit was taken offline for the refurbishment in January 2020 - just as the COVID-19 pandemic was beginning. The impacts and uncertainty of the pandemic presented a "major hurdle" to Bruce Power and its construction partners, the company said, but the substantial completion of the construction phase has been completed on time and on budget.

The construction phase of the unit 6 MCR, completed with execution partner Shoreline Power Group as well as tradespeople from the Ontario Building Trades, included the removal and replacement of 960 fee­der tubes, 480 fuel channels, and 480 calandria tubes. Steam generator work was completed earlier this year by SGRT, a joint venture of Aecon and Framatome and United Engineers & Constructors partnership SGT.

Refuelling the unit with 5760 fuel bundles will begin this month, and other lead-out activities and regulatory inspections will now be completed with the goal of grid reconnection in the fourth quarter of this year.

The MCR of a second Bruce reactor formally began in March, when unit 3 was removed from service for defuelling and other preparatory works prior to the start of construction activity, which will begin with major component disassembly later this quarter. Each successive outage over the next decade will build on the successes and innovations of the Unit 6 MCR, the company said.

"The unit 6 MCR outage wasn't without its challenges for Bruce Power and our construction and supply chain partners," Bruce Power President and CEO Mike Rencheck said. "I am proud of how we all worked together, especially during the COVID-19 pandemic, to finish construction building activities, and set ourselves up for success in our subsequent MCRs. We learned a lot, and new innovations will be implemented on future MCRs making them faster and less expensive."

The refurbishment of Bruce units 3-8 is scheduled to be fully completed by 2033 (units 1 and 2 at the site have already been refurbished). The MCR project and Bruce Power's Life-Extension Program will extend the operational life of each reactor by 30 to 35 years, helping to mitigate predicted increases in greenhouse gas emissions from the electricity grid, the company said. The work is also being coordinated with the Project 2030 programme, which aims to leverage innovation and new efficient technology to increase site capacity to over 7000 MWe of net peak output in the early 2030s, once all units have completed their MCRs.

The work is expected to generate billions of dollars of economic benefits throughout the province of Ontario as well as directly and indirectly supporting 22,000 jobs per year.

"Nuclear energy is crucial to powering our growing province and thriving economy and the completion of construction on Bruce Power's Unit 6 Major Component Replacement Project is a critical step as we ensure the province can meet the demand for clean, low-cost electricity," said Ontario Minster of Energy Todd Smith.

Researched and written by World Nuclear News