Bruce refurb and uprate project progresses

11 January 2008

Bruce Power continues to make progress onthe refurbishment of its Bruce A nuclear power plant and the uprate ofBruce B in Ontario, Canada. All the replacement steam generators havenow been delivered for units 1 and 2, while three of the units have nowbeen uprated.

The Bruce site hosts eight reactors built in two large blocks of four each. Bruce A contains units 1 to 4, Bruce B has units 2 to 8.

Units 1 and 2 started commercial operation in 1977 but unit 2 was shut down in 1995 due to a maintenance accident in which lead contaminated the core. Unit 1 was laid up with another six units at the end of 1997 to allow operational focus on newer plants.

 

However, facing an impending power shortage, the Ontario government in October 2005 agreed with Bruce Power to refurbish the Bruce A units, each 769 MWe, rather than the longer process of building new ones to replace them.

 

Bruce 1 and 2 are now having their fuel channels and steam generators replaced and ancillary systems upgraded to current standards, giving them a further 25-year life from 2009-10 when they are set to restart. Units 3 and 4 will then have their fuel channels and steam generators replaced by 2012, giving them another 25 years operation. It had been planned to shut down unit 4 at the end of 2017, but with the other work running on time and within budget, plans for refurbishment of it were announced in 2007, at an extra cost of $1 billion.

 

As part of the project to restart Bruce units 1 and 2, 16 new steam generators were required. The last of these was successfully lifted into place using a 100 tonne crane on 8 January by SNC-Lavalin.

Duncan Hawthorne, Bruce Power's President and CEO, remarked, "This is a significant day for us and a symbolic one for many people in our community. The need for new boilers was a big reason why Bruce A was prematurely closed in the 1990s, which impacted many people's lives. To see these new vessels in place affirms how times have changed and that our restart project is progressing well."

 

Each Bruce A unit has eight steam generators. The replacement steam generators were supplied by Babcock & Wilcox Canada in Cambridge, Ontario, under a contract signed in 2005. The replacement components were manufactured using Alloy 800 tubes employing design enhancements.


 

Meanwhile, the Bruce 5 unit has been 'uprated' by 3%. Bruce Power said that fuel-loading modifications will allow operators to safely raise the reactor power from 90% to 93%. Earlier uprates at unit 6 and 7 of the Bruce plant resulted in some 30 MWe increases in output. Unit 8 is expected to be uprated by 2009.

 

Hawthorne said: "Since 2001, we have embarked on a program of investment and innovation to find ways to safely increase our output." He added, "Through a combination of fuelling improvements and new turbine rotors at Bruce B, the results of those investments are now being realized. By restarting new units at Bruce A and improving the way we operate our Bruce B units, output on our sites rise by more than 60% in the last six years, which has gone a long way to helping Ontario meet its power needs."