Argentina operates two nuclear reactors that provide less than 6.2% (down from 9% in 2003) of the country’s electricity. Argentina was one of the countries that embarked on an ambiguous nuclear program, officially for civil purposes but with a strong military lobby behind it.
Nevertheless, the two nuclear plants were supplied by foreign reactor builders, Atucha-1, a heavy water reactor of a unique design which started operation in 1974, was supplied by Siemens and the Candu type reactor at Embalse by the Canadian AECL. Embalse was connected to the grid in 1983. Atucha-2, officially listed as “under construction” since 1981, was to be built by a joint Siemens-Argentinean company “that ceased in 1994 with the paralization of the project”.319 Nevertheless, in 2004 the IAEA estimated that the start-up of Atucha-2 was to be expected in 2005. At the end of 2007, the IAEA’s expected start-up date had turned into a question mark that was replaced by 1 October 2010 as a new projected date for grid connection. By the middle of 2008 the plant was about 80% complete.
In July 2007 Argentina’s Nucleoelectrica signed an agreement with Atomic Energy of Canada Ltd (AECL) to enter into commercial negotiations over the potential delivery of a 740 MW Candu-6 reactor. In early May 2009 Julio de Vido, Argentina’s Minister of Planning and Public Works, stated that planning for a fourth nuclear reactor would be underway and that construction could start as early as within one year.320 However, no siting decision, nor any call for tender has been reported to date.
Not the CANDU specifically but since we are talking about Economic Hitmen...
Brazil operates two nuclear reactors that provide the country with 3.1% of its electricity (down from 4% in 2003). As early as 1970, the first contract for the construction of a nuclear power plant, Angra-1, was awarded to Westinghouse. The reactor went critical in 1981. In 1975, Brazil signed with Germany what remains probably the largest single contract in the history of the world nuclear industry for the construction of eight 1,300 MW reactors over a 15 year period. The outcome was a disaster. Due to an ever-increasing debt burden and obvious interest in nuclear weapons by the Brazilian military, practically the entire program was abandoned. Only the first reactor covered by the program, Angra-2, was finally connected to the grid in July 2000, 24 years after construction started.
The construction of Angra-3 was abandoned in June 1991. Hopes of Eletronuclear, the owner of the plant, to relaunch construction received a severe damper in July 2008 when Environment Minister Carlos Minc announced 60 stiff “pre-license” conditions for the completion of the unit. The most difficult challenge will no doubt be to provide a “definite” solution for final disposal of high-level radioactive waste. Indeed, the completion of Angra-3 now “looks more doubtful”.322
Canada was one of the early investors in nuclear power and began developing a new design of heavy water reactor in 1944. This set the development of the Canadian reactor program down a unique path, with the adoption of the Candu – CANadian Deuterium Uranium – reactor design. The key differences between the Candu and the more widely adopted light water reactors are that they are fuelled by natural uranium, can refuel without shutting down and are cooled and moderated by heavy water.
Officially, there are 18 reactors in operation, all of which are Candus providing 14.8% (up from 12.5% in 2003) of the country’s electricity. Four additional units are listed by the IAEA as in “long term shutdown”. Throughout their operational history the Canadian reactors have been plagued by technical problems that led to construction cost over-runs and reduced annual capacity factors. In August 1997 Ontario Hydro announced that it would temporarily shut down its oldest seven reactors to allow a significant overhaul to be undertaken. The four reactors at Pickering-A were shut down at the end of 1997 with the three remaining Bruce-A reactors closed on 31 March 1998 - unit 2 at Bruce A had already been closed in October 1995. At the time it was the largest single shutdown in the international history of nuclear power -- over 5,000 MW of nuclear capacity, one third of Canada’s nuclear plants. The utility, Ontario Hydro, called for the “phased recovery” of its nuclear reactors starting with “extensive upgrades” to the operating stations - Pickering B, Bruce B, and Darlington - and then their return to service. There have been significant delays in restarting the reactors and as of May 2009 only four of the eight reactors had returned to operation; two more are scheduled to come back online later in 2009 or early 2010. The two remaining Bruce-A3 and - A4, according to Bruce Power “one of North America’s most complex engineering projects”, are slated to be back online by 2013.323
In March 2009, Bruce Power announced that it is looking at the Whitemud site close to Lac Cardinal in Alberta for a nuclear plant of up to 4,000MW. The company had selected another site a year earlier but abandoned it following massive opposition. Bruce Power predicts a 10-year site preparation and construction phase, so that the units would start up well after 2020. No decision has been taken at this point.
On 16 June 2008 the Canadian government announced Darlington in Ontario as the site for a two-unit new build project and on 20 May 2009 information leaked that the Ontario government had chosen AECL as the leading bidder over AREVA and Westinghouse to start building the first new nuclear plants in Canada in 25 years. Two new reactors were projected to start operating by 2018.
However, the provincial government reportedly conditioned any go-ahead on financial guarantees by the federal government to cover the financial risks involved.324
In early July 2009, the Ontario government shelved the entire plan and Premier McGuinty stated: "We didn't factor in the single greatest global economic recession in the past 80 years."325 So power needs were actually declining rather than increasing as had been forecasted, leaving the province with more time to make a decision on new build.
New Brunswick is investigating the option of adding a second nuclear reactor at its Point Lepreau site; but meanwhile a $1.4 billion refurbishment project on the first unit is running at least three months late and could extend well into 2010. The unit has been down since April 2008.
Any new-build plan in Canada risks running into massive difficulties. There is substantial local opposition against projects, in particular in Alberta and Saskatchewan. The industry would have to cope with extensive refurbishment and new-build activities at the same time. As in other countries, the Canadian nuclear industry faces a severe shortage in skilled workers. The President of the Canadian Nuclear Safety Commission (CNSC) has stated that CNSC is "facing many of same issues as the rest of the nuclear industry", including a 10% annual turnover and 23% of the workforce eligible to retire in the next five years.326 New build would also involve a new design of Candu, ACR-1000, which, unlike the earlier plants, would use light water as coolant. This would have to undergo a thorough regulatory review and its costs are therefore, as yet, impossible to estimate.
AECL has, with the support of the Canadian Export Credit Agency, undertaken an aggressive marketing campaign to sell reactors abroad and to date 12 units have been exported to South Korea (4), Romania (2), India (2), China (2), Pakistan (1), Argentina (1). The export market remains a crucial component of the AECL’s reactors development program. In September 2004, a Memorandum of Understanding was signed with the National Nuclear Safety Administration of China. This MoU will in part facilitate the development of AECL’s Advanced Candu Reactors. Canada is the world’s largest producer of uranium and in 2008 produced about 21% of the global total.
All of above from Open Access Doc:
The World Nuclear Industry Status Report 2009
With Particular Emphasis on Economic Issues
Paris, August 2009
Commissioned by
German Federal Ministry of Environment, Nature Conservation and Reactor Safety
(Contract n° UM0901290)
From the Home of the CANDU:
In the belly of the nuclear beast, the massive domes of the reactors rise ominously to a height of more than 45 m, their radioactive interiors visible only through the thick windows of airlocks. One level up at Ontario Hydro’s sprawling Pickering station, 40 km east of Toronto, steam-driven turbines crouch under an array of blue, green and yellow pipes. Nearby, many of the 25 years’ worth of spent nuclear fuel rods stored at Pickering lie beneath 3.5 m of water in an eerily shimmering pool. Inside the plant, it is hot, noisy and hectic as members of the 2,800-strong workforce go about their business. And on a typical day earlier this year, all seemed well. Two of Pickering’s eight CANDU reactors were shut down for routine maintenance, while the remaining six sent about 3,000 megawatts of electricity surging into the provincial grid - enough, in normal circumstances, to supply every home, office and factory in Metropolitan Toronto.
But beneath the surface, there were festering, potentially deadly problems at Pickering and elsewhere among Hydro’s 19 working reactors - as last week’s report on the corporation’s nuclear division scathingly demonstrated. The flaws go beyond the poor safety training and sloppy operating practices highlighted in the report. Ontario’s CANDUs are growing old - and the four venerable A units at Pickering and three more at the Bruce generating station on the shores of Lake Huron, all of which Ontario Hydro has decided to mothball, may never resume operation. Reason: the reactors, which went into service between 1971 and 1979 - and were designed to last 40 years - are plagued by troubles that include worn pressure tubes, which will soon be in need of replacement, faulty steam generators, and safety features that fall short of the standards set by the Atomic Energy Control Board (AECB), the federal body that regulates the nuclear industry. "For years, Ontario Hydro has been living in a dream world," says Gordon Edwards, spokesman for the Montreal-based Canadian Coalition for Nuclear Responsibility. "Now, they’re experiencing a shock of recognition and admitting that everything is not OK."
Hardware failings have also emerged at the two Canadian-operated CANDUs outside of Ontario - at Gentilly, Que., and Point Lepreau, N.B. At both reactors, corrosion has thinned some feeder pipes that carry radioactive heavy water from the reactor core to steam-generating boilers. Atomic Energy of Canada Ltd. officials say the corrosion has been arrested, but Julie Dingwell, of the Saint John,
N.B.-based group People Against Lepreau, worries that the deficiencies in Ontario’s nuclear network may afflict all CANDU operations. "The safety margins have not been good," says Dingwell. "It’s really frightening." Nuclear officials maintain that many of the equipment problems are normal and acceptable. "You have to look at the broad context," says Gary Kugler, a vice-president at Mississauga, Ont.-based Atomic Energy of Canada Ltd., the Crown corporation that designed and exports the CANDU. "All machinery, including nuclear reactors, shows wear and tear after a length of time." But David Martin, spokesman for the Pickering-area anti-nuclear organization Durham Nuclear Awareness, insists that Ontario Hydro and other reactor operators in Canada face a "fundamental technology problem. Ontario Hydro is shutting down its oldest reactors because they have too many defects - and I predict that they will never be restarted."
When the CANDU (for Canadian deuterium uranium reactor) was designed back in the 1950s, its basic features were supposed to make it more versatile, cheaper to operate and safer than its competitors. At the heart of the CANDU are pellets of radioactive uranium dioxide fuel assembled into pencil-shaped sheaths that, in turn, are grouped inside six-metre-long pressure tubes. Hundreds of tubes are installed in each reactor, where heavy water - also known as deuterium oxide, a molecule containing an extra-large hydrogen atom - slows the movement of free neutrons generated by the uranium. This increases the chances that the neutrons will split uranium atoms and release their pent-up energy in a controlled chain reaction. When that happens, energy is transferred to the heavy water, which heats ordinary water to create steam that drives turbines to produce electricity.
As with many reactors, flaws were inadvertently built into the CANDU from the start...
http://www.encyclopediecanadienne.ca/index.cfm?PgNm=TCE&Params=M1ARTM0011389 
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