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Nuclear Power in Canada — An Overview

By Dave Martin, Policy Advisor, Sierra Club of Canada

There are 22 CANDU power reactors in Canada, of which 20 are in Ontario, one in Quebec and one in New Brunswick. As these CANDU reactors have aged, they have experienced increasing technical problems and dramatically poorer performance. Although it was assumed that reactors would last for forty years, they are typically experiencing serious operational problems much earlier.

[NB all $ figures are quoted in CDN dollars]


Ontario Hydro (the generating wing of which is now Ontario Power Generation — OPG) announced in August 1997 that it would temporarily shut down its oldest seven reactors because of poor performance and safety concerns. This included four 515 MWe(net) reactors at the Pickering “A” nuclear station, just east of Toronto, and three 848 MWe(net) reactors at the Bruce “A” nuclear station on the shore of Lake Huron near the town of Kincardine. Ontario Hydro had already shut down reactor #2 at the Bruce “A” station in October 1995.

The four Bruce “A” reactors lasted on average less than half of their expected 40-year lifetimes, before being shut down for long-term repair work. The Pickering “A” reactors lasted only 25 years, despite having been re-tubed at a cost of $1 billion following a disastrous pressure tube break at Pickering reactor #2 in 1983. The shutdowns left Ontario Power Generation with 12 reactors in operation — four at the Pickering “B” station; four at the Bruce “B” station; and four at the Darlington station. The closure of eight reactors was the largest single long-term nuclear shutdown by any nuclear utility in the world.

The case of the four Pickering A reactors provides an instructive lesson as why nuclear refurbishment is ill-advised. In August 1983 a disastrous pressure tube rupture occurred in Pickering Reactor 2, and all four reactors at the Pickering A station were shut down. The pressure tubes of each reactor were replaced in succession over a ten year period. The retubing of the four reactors cost about $1 billion (dollars of the year) — more than their original capital cost. As noted above, despite this enormous investment, the reactors were shut down just a few years later at the end of 1997 because of technical and performance problems.

A controversial low level ('screening') environmental assessment conducted by the Canadian Nuclear Safety Commission (CNSC) from 1999-2000, and approved in February 2001. That assessment was condemned by environmental groups as a whitewash for failing to deal with vital issues such as severe accidents, the need for restart, financial cost, and energy alternatives.

When the four old Pickering A reactors were shut down on December 31, 1997, the first reactor (Unit 4) was supposed to restart in June 2000, with the remaining three to be restarted at six month intervals (to be completely operational by June 2002). OPG now hopes to have Pickering Reactor #4 in commercial service in July 2003, and is no longer making any public commitment for the restart of reactors 1, 2, and 3. If they are restarted at all, it has been suggested that reactors 1, 2, and 3 might be restarted at one-year intervals.

The cost of the Pickering A restart has escalated from $800 million in 1999 to $1.025 billion at the end of September 2002. It is estimated that the start-up of Reactor 4 will cost another $230 million, and the additional three reactors will cost $300 to $400 million each. Thus the cost for restarting reactor 4 alone will be $1.255 billion, with a likely additional $1.2 billion for the other three reactors, totaling $2.455 billion.

On May 30 2003, the Government of Ontario appointed a tribunal to review the delays and cost overruns on the refurbishment of the Pickering A nuclear station. Sierra Club Canada has condemned the review as a whitewash. The head of the review is former federal energy minister Jake Epp, notorious for his support of nuclear power. Another member of the tribunal is Robin Jeffrey, who oversaw the financial collapse in 2002 of British Energy, the United Kingdom nuclear company.

The case of the Bruce A reactors also provides cause for concern about nuclear refurbishment. The eight reactors at the Bruce nuclear complex on the shore of Lake Huron in Ontario were leased from Ontario Power Generation in May 2001 by Bruce Power for eighteen years. The Bruce complex includes four 769 MWe(net) reactors at the Bruce A station and four 860 MWe(net) reactors at the Bruce B station. While the four Bruce B reactors continue to operate, reactor #2 at the Bruce A nuclear station was shut down in October 1995, and reactors 1, 3 and 4 were shut down in March 1998 because of technical problems and poor performance.

In November 2000, Bruce Power hired Atomic Energy of Canada Limited (AECL) as the general contractor to lead an internal “inspection and condition assessment” of 70 fuel channels as well as steam generators for Bruce A reactors 3 and 4. The assessment cost $30 million and was intended to determine if the re-commissioning of the reactors was economically justified. On April 6, 2001, Bruce Power announced that it intended to restart reactors 3 and 4 at the Bruce A station. At that time, Bruce Power expected that the reactors would be restarted in the summer of 2003 at a total cost of about $340 million (CDN). The estimated refurbishment cost has escalated to $550 million, and the restart schedule has been speeded up to have reactor 4 restarting in May 2003, and reactor 3 shortly afterwards.

There are serious safety concerns with restart of the two Bruce reactors. There have been at least two cases of catastrophic pressure tube ruptures in Ontario reactors: August 1983 at Pickering 2 and March 1986 at Bruce 2. All fuel channels at the Pickering A station reactors were replaced after the 1983 accident. Bruce reactors 1 and 2 will require complete retubing if they are ever to be restarted. Some individual tubes at Bruce reactors have been replaced in the past, but Bruce Power is taking a calculated risk, trading off safety against profit by arguing that complete replacement of fuel channels is not necessary at Bruce reactors 3 and 4. Bruce Power has taken this controversial position despite having inspected only 7% of tubes. Complete retubing of the reactors would more than double the estimated $550 million restart cost as well as extending the outage time.

Outside of Ontario, there are only two nuclear power reactors in Canada — one operated by Hydro Québec (Gentilly 2) and one operated by New Brunswick Power (Point Lepreau). Both nuclear stations are single unit CANDU-6 reactors, i.e. 635 MWe(net) reactors, designed by Atomic Energy of Canada Limited (AECL). They both began commercial operation in 1983, and at twenty years of age both reactors need full-scale refurbishment if they are to continue operating.


The Point Lepreau Nuclear Generating Station is owned and operated by New Brunswick Power, and was designed by AECL. Like other reactors of the period, the Point Lepreau plant was intended to run for 40 years, however, after less than twenty years, the reactor experienced serious performance and safety problems. In 1998, an NB Power consultant decided that the plant would require total replacement of all 380 fuel channels in the 2006-2008 period. This has been characterized as a Œheart transplant’ for a CANDU reactor — essentially the reactor is re-built, requiring an extended outage for the plant, at an extremely high cost. As the first phase of a plan to retube and refurbish Point Lepreau, NB Power retained AECL in January 2001 to conduct a two-year assessment of the project at a cost of $40 million. According to the original schedule devised by AECL, Work Commencement was supposed to begin in February 2003. The plant would be shut down for an estimated 18 months beginning in April 2006, with project completion in September 2007. The total estimated cost of the project is $845 million.

In January 2002, New Brunswick Power filed an application to the New Brunswick Board of Commissioners of Public Utilities (known as the Public Utilities Board or PUB) to hold a public hearing on the refurbishment of the Point Lepreau nuclear station. The PUB released its decision on September 24, 2002. The PUB noted that its review was made from an economic perspective, but with a public interest viewpoint. The decision was a stunning rejection of AECL’s refurbishment proposal as put forward by NB Power…

    The Board […] finds that there is no significant economic advantage to the proposed refurbishment project. In addition, the Board considers that there are other significant aspects of the refurbishment option [which] is not in the public interest. The Board, therefore, will recommend to the Board of Directors of NB Power that it not proceed with the refurbishment of Point Lepreau.

In November 2002, NB Power retained a consulting firm to seek a purchaser or equity partners for Point Lepreau. The New Brunswick government and NB Power have also been seeking additional federal support for the refurbishment project. No decision has yet been made to proceed with the refurbishment.


Hydro Québec undertook an agreement in 1973 with the federal government to build Gentilly 2 — a standard AECL-designed CANDU-6 built at Bécancour, near Trois Rivières. The federal government agreed to finance 50% of the estimated $302 million capital cost of Gentilly-2 at a special low interest rate. However, Hydro Québec was solely responsible for the billion dollar cost overrun which saw the capital cost of the plant soar to $1.36 billion by the time it achieved first criticality in September 1982 — quadrupling the original estimate. Not surprisingly, the Québec government declared a moratorium on nuclear power plant construction in 1978.

In the 2001-2002 fiscal year, AECL signed contracts with Hydro Québec for the Gentilly 2 refurbishment pre-engineering work. In February 2002, Hydro Québec gave a Œnotice of project’ for the refurbishment of Gentilly 2 to the Quebec Ministry of the Environment. A decision is expected by the Hydro Québec Board of Directors in 2003, followed by the filing of an environmental impact study in the fall of 2003, which will allow engineering and tendering to take place by 2005. Enlargement of the radioactive waste facility would take place in 2006 and 2007, and the plant would be shut down for an 18 month period for the main refurbishment work from April 2008 to September 2009.

Given the position against the refurbishment of the Point Lepreau nuclear station taken by the New Brunswick Board of Commissioners of Public Utilities, it is logical that Province of Québec should reconsider its commitment to refurbish Gentilly 2. The Point Lepreau and Gentilly 2 plants are virtual duplicates, built at the same time with the same technology.

June 2003

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