The first commercial Candu reactors began operations in Pickering, Ontario, in Candu Energy would complete the refurbishment projects at Bruce, Point Lepreau, and Wolsong through subcontract service agreements with the Canadian government. About employees transferred to Candu Energy. By Candu Energy was focusing on adapting its designs to run on recycled uranium from light water reactors and thus to complement operators of those rather than compete with PWR and BWR designs.
As well as their use for electricity, Candu power reactors produce almost all the world's supply of the cobalt radioisotope for medical and sterilization use. To meet current and future electricity needs, provincial governments and power companies have made the decision to extend the operating life of a number of reactors by refurbishing them.
Refurbishing Candu units consists of such steps as replacing fuel channels and steam generators and upgrading ancillary systems to current standards.
While refurbishing usually takes less time and is less costly than building a new plant, there have been several cost overruns that in some cases have made it almost as expensive as new construction. This followed a review commissioned by Ontario Power Generation which was critical of the company's management and recommended a phased approach to improvement which involved the closure of seven reactors one was already shut down pending refurbishment and a focus on the other 12 then operating Bruce B, Pickering B and Darlington.
Of these eight Pickering A and Bruce A reactors four have been refurbished and returned to service, two are undergoing that now, and two at Pickering were considered uneconomic to refurbish so will not be restarted a. The Pickering A — Bruce A saga is a cautionary tale and classic industry case study regarding what is now called knowledge management KM.
By the mids there was a divergence between drawings and modifications which had progressively been made, and also the company had not shared operating experience with the designer. Maintenance standards fell and costs rose. A detailed audit showed that the design basis was not being maintained and that additional staff would be required to correct the situation at all Ontario Hydro plants, so the two A plants 8 units were shut down so that staff could focus on the 12 units not needing so much attention.
From , six of the eight A units were returned to service with design basis corrected, having been shut down for several years — a significant loss of asset base for the owners.
Full refurbishment of the later model Candu 6 units such as Point Lepreau includes replacement of all calandria tubes, steam generators and instrument and control systems. This first project went over time and budget, but the second, at Wolsong 1 in Korea, benefited from the experience. The four Pickering A reactors were laid up in Pickering A1 and A4 have both been refurbished in recent years, extending their life expectancy to and , respectively.
CNSC renewed the single operating licence of all six reactors for five years in August , subject to a whole-site probabilistic safety assessment focused on the B units The design limit for these units is normally , equivalent full-power hours.
This became the first Canadian reactor to clear the , hour limit. In November a study was released assessing the potential of running the six units MWe for a further four years from to In January the government approved OPG's plan for this, with two shutting down in and four in It is the licensee for the plant.
Units 3 and 4 of Bruce A had been laid up early in , and were returned to service in January and October , respectively as an early priority of Bruce Power. Facing an impending power shortage, the provincial government's Ontario Power Authority in October agreed with Bruce Power to refurbish its oldest Bruce A reactors.
Unit 2 had been laid up in due to a maintenance accident in which lead contaminated the core. Unit 1 was laid up along with the four Pickering A units at the end of , to allow operational focus on newer plants. Their operational lifetimes were extended by 25 years.
The installation of new calandria tubes was completed in November In July unit 1 was authorized to restart, and it was grid-connected in September. Unit 2 started up in March and came back on line in October, after sorting out a generator problem. They returned to commercial operation by October and November respectively. As part of the agreement, Bruce Power is paid for all electricity from Bruce A on the basis of a 6. The price is adjusted in line with the consumer price index.
One of the partners in Bruce Power at the time, Cameco Decisions on the four Bruce B reactors were pending, though in July Bruce Power announced that it would focus on refurbishing these rather than building new plants at Bruce, the expected cost being about half that of new plants. Effective at the end of December , Cameco sold its Bruce Power will continue to provide approximately one-third of its output 2, MW as flexible generation, allowing the province to permanently balance system needs in its post-coal environment.
These are Canada's newest Candu reactors and in November were licensed to Following detailed studies, OPG decided on full refurbishment starting in and consequent year lifetime extension. The work involves replacing fuel channels and upgrading ancillary systems to current standards as well as overhauling the turbine generators.
The Ontario government approved the project in January OPG plans to shut the reactors sequentially for approximately 3. CNSC has given environmental approval for the refurbishment, which will enable the units to continue operating for a further years, although this would be subject to separate licensing approvals.
Unit 3 — Q3 to Q1 — commenced September Unit 1 — Q1 to Q2 Unit 4 — Q3 to Q4 In June OPG announced that work had begun to reassemble the reactor of unit 2, and in November fuel loading began. In April the unit had reached criticality, and it returned to commercial operation in June The unit was shut down in October , before being isolated from the station, defuelled and the reactor components removed.
The last of its calandria tubes was removed in May In March OPG said that it would delay the planned start of unit 3's refurbishment, originally scheduled for May , as part of its plans to ensure supply of electricity during the Covid crisis. Work began in September Removal of the fuel bundles to storage was completed by the end of November In mid, the decision was made to refurbish New Brunswick Power's MWe Point Lepreau reactor, which provides one-quarter of the province's power.
It was the first Candu 6 type in commercial operation and was the first Candu-6 reactor to undergo full refurbishment, including replacement of all calandria tubes as well as steam generators. The project is expected to extend the life of the reactor to or beyond, and provide a 25 MWe uprate. In AECL decided to remove and reinstall all calandria tubes in the reactor core because of problems with the seals obtained for initial installation during the project.
The CNSC authorized fuel loading in March , restart in July, and grid connection in October , but it continued to operate at low capacity for some time.
It was at full capacity late in The provincial government sought to recover the overrun cost from the federal government. Two new low-pressure turbine rotors that were damaged in transit in were replaced in Most Quebec electricity is hydro, from the north of the province. Gentilly, close to the load centre, had particular importance for grid stability and it also provided energy security regardless of seasonal rainfall. There have been proposals to build several nuclear reactors to go into operation in the next decade, but these have been deferred, have lapsed or have been dropped in favour of major refurbishment of existing capacity.
Two reactors are proposed in Ontario, one was proposed in New Brunswick and one or possibly four smaller reactors were proposed in Alberta. In June , the Ontario government implemented a year energy plan, which envisaged maintaining existing nuclear generation capacity at 14, MWe.
Then the revision of the energy plan envisaged 12, MWe of nuclear capacity by out of a total installed capacity of around 41, MWe total capacity: 35, MWe. The plan called for an update in , which in the light of reduced power demand deferred the new construction at Darlington due to reduced demand forecasts. The update also scaled back refurbishment plans for Bruce A and Darlington, and said that Pickering might be closed earlier than In August , Bruce Power applied for a licence to prepare its 9.
Bruce Power submitted an environmental impact statement in September , showing that up to four new reactors at Bruce C would have no significant environmental effect. The new units were envisaged as coming on line beginning in Six different reactor types were under consideration. However, in July , the company announced that it would withdraw its site licence application and suspend its environmental assessment for Bruce C, and focus on refurbishment of Bruce A and B a major task — see above.
In September , Ontario Power Generation OPG applied for a licence to prepare its Darlington site for construction of up to four new nuclear power units. An updated application and the environmental impact statement were submitted in September An independent review panel appointed by the Environment Department and CNSC in concluded in August that the construction of up to four new reactors was unlikely to cause adverse environmental effects, and in May the environmental assessment was approved.
This was revoked by a federal court in May due to concerns about nuclear waste, hazardous emissions and accidents, but the CNSC appealed the decision on the grounds that these are matters for the construction and operating licences.
To keep the construction option open, OPG and the government aim to maintain the licence. In March , Ontario's Minister of Energy invited companies to submit proposals to build two new nuclear reactors at Darlington or Bruce, or both. In June , the Ontario government selected Darlington as the site for the two new nuclear reactors, to be operated by OPG and to come online in c. However, in June , the provincial government announced that the procurement process was being stalled pending resolution of the future of AECL d.
These were received in June , but further decisions were put on hold when the Ontario government deferred plans for construction in November In October , Bruce Power announced it would conduct an environmental assessment for two new nuclear units in the Haldimand-Norfolk region of southern Ontario.
In July , Bruce Power withdrew its site licence application and suspended its environmental assessment. In June the Energy Statute Law Amendment Act was passed, requiring a new long-term energy plan to be developed.
Near Surface Disposal Facility Project. Nuclear Power Demonstration Closure Project. Pickering Nuclear Generating Station. Port Granby Project. Port Hope Project. Port Hope Uranium Conversion Facility. SRB Technologies. Gentilly-1 Waste Facility. Gentilly-2 Nuclear Facility. This produces waste streams that are liquids and therefore virtually impossible to contain over the timescales on which they would have to be managed.
In security terms, reprocessing is precisely how the materials needed to produce nuclear weapons are obtained. In Canada, the Nuclear Waste Management Organization NWMO initially ruled out reprocessing as an option for managing waste nuclear fuel, given the waste management challenges and security risks.
It continues to express serious doubts about the benefits associated with the option. The other real problem with the SMR dream is that it has simply been overtaken by other technological developments. The past decade has seen dramatic declines in the cost of renewable energy sources. At the same time, major technological developments have occurred around a variety of energy storage technologies , vital to managing the intermittent nature of some renewables like solar and wind.
Finally, the information and control technologies needed to manage and integrate renewable and other low-impact energy resources into reliable energy supplies have matured. Simply put, cheaper, safer and cleaner options are available to support a low-carbon sustainable-energy transition in Canada.
Canadian governments would do well to put their investments in next generation clean energy and technology into those pathways, instead of an SMR dream that will never be realized. You are welcome to republish this Policy Options article online and in print periodicals. We ask that you follow these guidelines. Please attribute the author s and mention that the article was originally published by Policy Options magazine. Editing the piece is not permitted, but you may publish excerpts.
Originally published on Policy Options November 18, Republish this article.
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