Unit 6 at Canada’s Bruce NPP has achieved a sustained fission chain reaction following completion of its Major Component Replacement (MCR) Project. This followed Canadian Nuclear Safety Commission (CNSC) approval to begin releasing the unit from a Guaranteed Shutdown State which enabled the many commissioning activities to be completed on the newly installed systems to verify everything was working as expected. The 817 MWe (net) pressurised heavy water reactor was shut down in 2020 and is scheduled to resume commercial operation later this year.

“This is great progress, made possible by years of planning, preparation and execution by Bruce Power and our partners,” said Bruce Power President & CEO Mike Rencheck. “We are now in the final stages of returning unit 6 to service and we’re applying all of our learnings, innovation and experience from unit 6 to future MCRs to ensure our strong performance continues and improves.”

The MCR project began in January 2020. The eight pressurised heavy-water Candu reactor units at the Bruce site in Ontario (Bruce A – units 1-4, and Bruce B – units 4-8) began commercial operation between 1977 and 1987. Bruce Power’s CAD13bn ($10bn) Life Extension Programme, which includes Asset Management and MCR, began in 2016. MCR, which began with unit 6 and also includes units 3-8, will extend the life of the site until 2064. Units 1&2 have already been refurbished and were returned to service in 2012. Work began on unit 3 in March. This is a privately funded investment. The unit 6 MCR remains on track despite challenges faced during the COVID-19 pandemic, while work on the unit 3 MCR outage is also progressing on track.

The MCR project and Life-Extension Programme will extend the operational life of each reactor by 30-35 years. 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 by the early 2030s.

Image: Operators in the control room of Bruce 6 (courtesy of Bruce Power)