A core catcher is a device provided to catch the molten core material ( corium ) of a nuclear reactor in case of a nuclear meltdown and prevent it from escaping the containment building .
46-533: A core catcher is made from a special thermally resistant concrete ceramic to prevent nuclear core material from melting through the core catcher; it also has a cooling mechanism to cool down the core material. The core catcher of the European Pressurized Reactor (EPR) has 170 m expansion area and a mass of 500 t. Examples of reactor types with core catchers, besides the EPR, are: The AES-91 ,
92-676: A core catcher directly underneath the reactor. Thus, in early 2011, the two reactors of the Chinese Tianwan Nuclear Power Plant were the only working nuclear reactors with this type of core catchers. The Russian physicist who helped design the Russian core-catcher model during the Chernobyl crisis, Leonid Bolshov, has stressed that the experience of Chernobyl has encouraged Russia to create reactors with core-catcher safety devices in new nuclear plants. In 2018, Rosatom installed
138-596: A delay of fourteen years. The second EPR unit to start construction, at Flamanville in France, also suffered a more than decade-long delay in its commissioning (from 2012 to 2024). Two units at Hinkley Point in the United Kingdom received final approval in September 2016; the first unit was expected to begin operating in 2027, but was subsequently delayed to around 2030. EDF has acknowledged severe difficulties in building
184-518: A design maximum core damage frequency of 6.1 × 10 per station per year and a gross power output of 1770 MWe for a mains frequency of 50 Hz. The version submitted to the U.S. NRC has a power output of 1600 MWe (net). In 2013 , EDF acknowledged the difficulties it was having building the EPR design, with its head of production and engineering, Hervé Machenaud, saying EDF had lost its dominant international position in design and construction of nuclear power stations. Machenaud indicated EDF
230-409: A dispute over responsibility for the delays and final cost overruns. Areva settled the long-running dispute in 2018 by agreeing to pay €450 million for cost overruns and delays. As of May 2009, the station was at least three and a half years behind schedule and more than 50 percent over-budget. Areva and the utility involved "are in bitter dispute over who will bear the cost overruns and there
276-546: A joint effort of French Areva and German Siemens AG through their common subsidiary Areva NP, for Finnish operator TVO . Siemens ceased nuclear activities in 2011. Initial cost estimates were about €3.7 billion, but the project has since seen several severe cost increases and delays, with latest published cost estimates (from 2012) of more than €8 billion. The station was initially scheduled to go online in 2009. In May 2006, construction delays of about one year were announced, following quality control problems across
322-401: A long-term service contract with TNPJVC to support operations of the two EPRs. This contract covers nuclear plant outage and maintenance work, including spare parts supply and engineering services for eight years. In June 2021, higher than expected concentrations of radioactive gases were detected in the primary circuit of unit 1. This was later attributed to faulty fuel cladding. The reactor
368-426: A mains frequency of 50 Hz. It has 4 coolant loops with 1 steam generator per loop. There are concrete walls between loops and the hot and cold parts of each loop to protect against failures. Besides the double layer containment there is a concrete wall surrounding the primary system components inside the containment. The EPR design has several active and passive protection measures against accidents: The EPR has
414-450: A new model EPR] is neither a priority or a plan. Right now the priority is to develop renewable energy and to reduce the share of nuclear." The industry-government plan for 2019–2022 included work on "a new version of the EPR". In July 2019, the French nuclear safety authority ASN issued an opinion on the safety of an outlined new EPR model (EPR2) design. It found that general safety was on
460-486: A number of iterations. The 1994 conceptual design had a power output of 1450 MWe, the same as the Framatome N4, but using Siemens Konvoi derived instrumentation and also including a new core catcher safety system. By 1995, there was concern over excessive cost per MW, and output was raised to 1800 MWe in the 1997 design, though this was subsequently reduced to 1650 MWe (net) in the final certified design, for
506-456: A project of Atomstroyexport based on the VVER-1000 design, was envisaged to be the first type of nuclear plant to have a core catcher directly underneath the reactor. Thus, in early 2011, the two reactors of the Chinese Tianwan Nuclear Power Plant were the only working nuclear reactors with this type of core catchers. The Russian physicist who helped design the Russian core-catcher model during
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#1733085318913552-481: A test production phase. On 28 October 2022, it was announced cracks of a few centimetres had been found in all four of the feedwater pump impellers. The cause of the cracks was yet to be determined, and it was unclear how the commissioning schedule would be affected. The feedwater pumps are larger than in other nuclear reactors. Olkiluoto 3 started regular electricity production in April 2023. In 2006, Areva took part in
598-482: Is a Generation III+ pressurised water reactor design. It has been designed and developed mainly by Framatome (part of Areva between 2001 and 2017) and Électricité de France (EDF) in France, and by Siemens in Germany. In Europe this reactor design was called European Pressurised Reactor , and the internationalised name was Evolutionary Power Reactor , but is now simply named EPR . The first operational EPR unit
644-495: Is a real risk now that the utility will default". In August 2009, Areva announced €550 million additional provisions for the build, taking station costs to €5.3 billion, and wiped out interim operating profits for the first half-year of 2009. The dome of the containment structure was topped out in September 2009. 90% of procurement, 80% of engineering works and 73% of civil works were completed. In June 2010, Areva announced €400 million of further provisions, taking
690-427: Is no longer able to finance EPR2 construction on its own, so financing and profitability issues need to be resolved. The audit office requires that EDF ensure the financing and profitability of EPR2 before constructing any in France. In January 2022, junior environment minister Bérangère Abba said that plans for new EPR2 reactors, to be operational between 2035 and 2037, should be submitted around 2023. The decision
736-594: Is that, unlike the first EPR design, the EPR2 design does not allow access to the reactor building for maintenance during reactor operation, which simplifies the design of the reactor building. In 2020, French Energy Minister Élisabeth Borne announced the French government would not decide on the construction of any new reactors until the much delayed Flamanville 3 started operation after 2022. EDF had estimated that building six EPR2 nuclear reactors would cost at least €46 billion. A Court of Audit report concluded that EDF
782-577: Is the China General Nuclear Power Group (CGN). The construction of the first reactor at Taishan started officially on 18 November 2009, and the second on 15 April 2010. Construction of each unit was then planned to take 46 months, significantly faster and cheaper than the first two EPRs in Finland and France. The reactor pressure vessel of the first reactor was installed in June 2012, and
828-483: Is the evolutionary descendant of the Framatome N4 and Siemens Power Generation Division " Konvoi [ de ] " reactors. Siemens ceased its nuclear activities in 2011. The EPR was designed to use uranium more efficiently than older Generation II reactors , using approximately 17% less uranium per kilowatt-hour of electricity generated than these older reactor technologies. The design has gone through
874-424: The Chernobyl crisis, Leonid Bolshov, has stressed that the experience of Chernobyl has encouraged Russia to create reactors with core-catcher safety devices in new nuclear plants. In 2018, Rosatom installed a 200-tonne core catcher at Bangladesh's Rooppur 1 Nuclear Power Plant (planned to go into operation in 2023), describing it as "a unique protection system". European Pressurized Reactor The EPR
920-721: The EPR design. In September 2015, EDF stated that the design of a "New Model" EPR (later named EPR2 ) was being worked on and that it would be easier and cheaper to build. The main objectives of the third generation EPR design are increased safety while providing enhanced economic competitiveness through improvements to previous pressurised water reactor designs scaled up to an electrical power output of around 1650 MWe (net) with thermal power of 4500 MW. The reactor can use 5% enriched uranium oxide fuel, reprocessed uranium fuel or 100% mixed uranium plutonium oxide fuel, clad in Areva's M5 variant of zirconium alloy . The EPR
966-552: The EPR2 is being developed using three instead of four coolant loops generating 1200 MWe net, the EPR1200, intended for export. In February 2023, regulator ASN issued a positive opinion on the safety features of the EPR1200. Construction of the Olkiluoto 3 power station in Finland began in August 2005. The station has an electrical power output of 1600 MWe (net). The construction was
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#17330853189131012-423: The French nuclear safety authority ( Autorité de sûreté nucléaire , ASN) reported that a quarter of the welds inspected in the secondary containment steel liner are not in accordance with norms, and that cracks have been found in the concrete base. EDF stated that progress was being made on these issues, which were raised very early in construction; however, on 21 May, ASN ordered a suspension of concrete pouring on
1058-482: The Italian power company Enel announced it was relinquishing its 12.5% stake in the project, and five future EPRs, so would be reimbursed its project stake of €613 million, plus interest. In November 2014, EDF announced that completion of construction was delayed to 2017, due to delays in component delivery by Areva. In April 2015, Areva informed the French nuclear regulator ASN that anomalies had been detected in
1104-491: The construction. In part, the delays were due to the lack of oversight of subcontractors inexperienced in nuclear construction. The delays led to disappointing financial results for Areva. It blamed delays on the Finnish approach to approving technical documentation and designs. In December 2006, TVO announced construction was about 18 months behind schedule so completion was now expected 2010–11, and there were reports that Areva
1150-414: The core catcher; it also has a cooling mechanism to cool down the core material. The core catcher of the European Pressurized Reactor (EPR) has 170 m expansion area and a mass of 500 t. Examples of reactor types with core catchers, besides the EPR, are: The AES-91 , a project of Atomstroyexport based on the VVER-1000 design, was envisaged to be the first type of nuclear plant to have
1196-474: The cost overrun to €2.7 billion. The timescale slipped from June 2012 to the end of 2012. In December 2011, TVO announced a further delay to August 2014. As of July 2012, the station was scheduled to start electricity production no earlier than 2015, a schedule slippage of at least six years. In December 2012 Areva's Chief Executive estimated costs to €8 billion. In September 2014, Areva announced that operations would start in 2018. In October 2017,
1242-576: The date was pushed back to the spring of 2019. During testing between 2018 and 2021, multiple further delays were announced, of around three years in total. Olkiluoto 3 achieved first criticality in December 2021. Grid connection took place in March 2022. In May 2022, foreign material was found in the turbine steam reheater, and the plant was shut down for about three months of repair work. Regular production had been expected to begin in December 2022, after
1288-431: The electrical buildings can be completely prefabricated. The fourth emergency/safety cooling system/train of the reactor is removed which means maintenance can only be performed when the plant is shut down. This train was added at the request of German electricians in the original EPR design to allow for on-power maintenance. The core catcher has been modified. It has a net power output of 1670 MWe. A smaller variant of
1334-745: The first bidding process for the construction of four new nuclear reactors in China, together with Toshiba-owned Westinghouse and Russian Atomstroyexport . However Areva lost this bid in favour of Westinghouse's AP1000 reactors, in part because of Areva's refusal to transfer the expertise and knowledge to China. Subsequently, Areva managed to win a deal in February 2007, worth about €8 billion ($ 10.5 billion) for two EPRs located in Taishan , Guangdong Province in southern China, in spite of sticking to its previous conditions. The General Contractor and Operator
1380-526: The first half of 2017. Taishan 2 was scheduled to start up later that year. However, commissioning dates were put back six months in February 2017, with commercial operation expected in the second half of 2017 and the first half of 2018. In December 2017, Hong Kong media reported that a component had cracked during testing, needing to be replaced. In January 2018, commissioning was rescheduled again, with commercial operation expected in 2018 and 2019. In June 2018, Taishan 1 achieved criticality for
1426-595: The first time. On 29 June 2018, Taishan 1 was connected to the grid. It entered commercial operation in December 2018. Taishan 2 reached these milestones in May 2019 June 2019 and September 2019, respectively. The Taishan project is led by Taishan Nuclear Power Joint Venture Co. (TNPJVC), a joint venture founded by CGN (51% ownership stake), EDF (30%), and Chinese utility Guangdong Energy Group (19%), also known as Yuedian. Companies involved in supplying equipment to Taishan Unit 1 include Framatome, which manufactured
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1472-474: The project was submitted to a national public debate. On 4 May 2006, the decision was made by EDF's Board of Directors to continue with the construction. Between 15 June and 31 July 2006, the unit underwent a public enquiry, which rendered a "favourable opinion" on the project. That summer, site preparation works began. In December 2007, construction of the unit itself began. This was expected to last 54 months, with commissioning planned for 2012. In April 2008,
1518-550: The reactor building to withstand an aeroplane crash, and the timely supply of adequate documentation to the Finnish authorities. In September 2007, TVO reported the construction delay as "at least two years" and costs more than 25% over budget. Cost estimates by analysts for the overrun range up to €1.5 billion. A further delay was announced in October 2008, making the total delay three years, giving an expected online date of 2012. The parties entered into arbitration to resolve
1564-414: The reactor vessel steel, causing "lower than expected mechanical toughness values". Further tests are underway. In July 2015 The Daily Telegraph reported that Areva had been aware of this problem since 2006. In June 2015, multiple faults in cooling system safety valves were discovered by ASN. In September 2015, EDF announced that the estimated costs had escalated to €10.5 billion, and the start-up of
1610-403: The reactor was delayed to the fourth quarter of 2018. Core catcher A core catcher is a device provided to catch the molten core material ( corium ) of a nuclear reactor in case of a nuclear meltdown and prevent it from escaping the containment building . A core catcher is made from a special thermally resistant concrete ceramic to prevent nuclear core material from melting through
1656-631: The second in November 2014. The first pressure vessel had been imported from Mitsubishi Heavy Industries in Japan, and steam generators from Areva in France. The second pressure vessel and associated steam generators had been made in China, by Dongfang Electric and Shanghai Electric . In 2014, construction was reported to be running over two years late, mainly due to key component delays and project management issues. Cold function tests were performed on Taishan 1 in February 2016, with start up expected in
1702-443: The secondary containment steel liner. The same month, EDF announced that costs had increased 50% to €5 billion, and commissioning was delayed by about two years to 2014. In July 2011, EDF announced that the estimated costs had escalated to €6 billion, and that completion of construction was delayed to 2016. In December 2012, EDF announced that the estimated costs had escalated to €8.5 billion. Also in December 2012,
1748-440: The site. A month later, concreting work resumed after ASN accepted EDF's corrective action plan, which included external oversight checks. In May 2009, Stephen Thomas reported that after 18 months of construction, and after a series of quality control problems, the project is "more than 20 percent over budget and EDF is struggling to keep it on schedule". In August 2010, the regulator, ASN, reported further welding problems on
1794-487: The steam generators and pressurizer in France, and China’s Dongfang Electric Corp. (DEC), which manufactured the Arabelle turbine in the engine room. That turbine was designed and licensed by General Electric. Other equipment suppliers for Unit 1 include Mitsubishi (reactor vessel); Škoda, a Czech company (core internals); and France’s Jeumont Electric, which along with DEC provided primary pumps. In April 2020, Framatome signed
1840-452: The whole satisfactory, though identifying areas for further examination. The most notable simplification is a single layer containment building with a liner as opposed to the EPR's double layer with a liner. ASN highlighted that the EPR design basis assumption that primary and secondary cooling circuit piping would not fail may no longer be appropriate for the simplified EPR2, and requires additional safety demonstrations. Another simplification
1886-408: Was China's Taishan 1 , which started commercial operation in December 2018. Taishan 2 started commercial operation in September 2019. European units have been so far plagued with prolonged construction delays and substantial cost overruns. The first EPR unit to start construction, at Olkiluoto in Finland, originally intended to be commissioned in 2009, started commercial operation in 2023,
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1932-416: Was accelerated by the impact of the 2021 global energy crisis . In June 2023, EDF announced it was starting the authorisation process to build two EPR2 reactors at Penly Nuclear Power Plant . The EPR2 requires 250 types of pipes instead of 400 for the EPR, 571 valves instead of 13,300 valves for the EPR, and 100 types of doors instead of 300 in the EPR. The EPR2 also uses more prefabricated components, and
1978-596: Was being worked on, which would be easier to build, and be ready for orders from about 2020, describing it in 2016 as "a reactor offering the same characteristics as today’s EPR but it will be cheaper to build with optimised construction times and costs". In 2016, EDF planned to build two new model EPR reactors in France by 2030 to prepare for renewing its fleet of older reactors. However, following financial difficulties at Areva and its merger with EDF, French Ecology Minister Nicolas Hulot said in January 2018, "for now [building
2024-409: Was considering designing two new lower powered reactors, one with output of 1500 MWe and the other 1000 MWe. Machenaud stated there would be a period of reflection on the best way to improve the EPR design to lower its price and incorporate post-Fukushima safety improvements. In September 2015, EDF's chief executive Jean-Bernard Lévy stated that the design of a "New Model" EPR, or "EPR2",
2070-476: Was preparing to take a €500 million charge on its accounts for the delay. At the end of June 2007, it was reported that Säteilyturvakeskus (STUK), the Finnish Radiation and Nuclear Safety Authority, had found a number of safety-related design and manufacturing 'deficiencies'. In August 2007, a further construction delay of up to a year was reported associated with construction problems in reinforcing
2116-679: Was taken offline in July 2021 and restarted in August 2022. First concrete was poured for the demonstration EPR reactor at the Flamanville Nuclear Power Plant on 6 December 2007. As the name implies, this will be the third nuclear reactor on the Flamanville site, and the second instance of an EPR being built. Electrical output will be 1630 MWe (net). The project was planned to involve around €3.3 billion of capital expenditure from EDF . From 19 October 2005 to 18 February 2006,
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