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36-535: VVER power stations have been installed in Russia, Ukraine, Belarus, Armenia, China, the Czech Republic, Finland, Hungary, Slovakia, Bulgaria, India, and Iran. Countries that are planning to introduce VVER reactors include Bangladesh, Egypt, Jordan, and Turkey. Germany shut down its VVER reactors in 1989-90, and cancelled those under construction. The earliest VVERs were built before 1970. The VVER-440 Model V230

72-655: A core catcher to contain the molten reactor core in the event of a severe accident. The core catcher will be deployed in the Rooppur Nuclear Power Plant and El Dabaa Nuclear Power Plant . The VVER-TOI is developed from the VVER-1200. It is aimed at development of typical optimized informative-advanced project of a new generation III+ Power Unit based on VVER technology, which meets a number of target-oriented parameters using modern information and management technologies. The main improvements from

108-521: A district heating supply network in the town of Trnava near Bohunice NPP, V2 switched to co-generation . Part of this system is a heat feeder line commissioned in 1987. In 1997, a heat feeder line to Leopoldov and Hlohovec was created, branching off from the Trnava line. The A1 is a nuclear reactor situated on the Jaslovské Bohunice site. It was built between 1958 and 1972, and it was

144-695: A 2.4 GWe nuclear power plant in Bangladesh. The two units generating 2.4 GWe are planned to be operational in 2023 and 2024. On 7 March 2019 China National Nuclear Corporation and Atomstroyexport signed the detailed contract for the construction of four VVER-1200s , two each at the Tianwan Nuclear Power Plant and the Xudabao Nuclear Power Plant . Construction will start in May 2021 and commercial operation of all

180-565: A gross and net thermal efficiency of 37.5% and 34.8%. The VVER 1200 will produce 1,198 MWe of power. VVER-1200 has a 60 years design lifetime with the possibility of extension by 20 years. The first two units have been built at Leningrad Nuclear Power Plant II and Novovoronezh Nuclear Power Plant II . More reactors with a VVER-1200/491 like the Leningrad-II-design are planned ( Kaliningrad and Nizhny Novgorod NPP) and under construction. The type VVER-1200/392M as installed at

216-621: A lake or river. Evaporative cooling towers, cooling basins or ponds transfer the waste heat from the generation circuit into the environment. In most VVERs this heat can also be further used for residential and industrial heating. Operational examples of such systems are Bohunice NPP ( Slovakia ) supplying heat to the towns of Trnava (12 kilometres [7.5 mi] away), Leopoldov (9.5 kilometres [5.9 mi] away), and Hlohovec (13 kilometres [8.1 mi] away), and Temelín NPP ( Czech Republic ) supplying heat to Týn nad Vltavou 5 kilometres (3.1 mi) away. Plans are made to supply heat from

252-434: A moderator which is an important safety feature. Should coolant circulation fail, the neutron moderation effect of the water diminishes due to increased heat which creates steam bubbles which do not moderate neutrons, thus reducing reaction intensity and compensating for loss of cooling , a condition known as negative void coefficient . Later versions of the reactors are encased in massive steel reactor pressure vessels. Fuel

288-430: Is low enriched (ca. 2.4–4.4% U) uranium dioxide (UO 2 ) or equivalent pressed into pellets and assembled into fuel rods. Reactivity is controlled by control rods that can be inserted into the reactor from above. These rods are made from a neutron absorbing material and, depending on depth of insertion, hinder the chain reaction . If there is an emergency, a reactor shutdown can be performed by full insertion of

324-622: Is a complex of nuclear reactors situated 2.5 km from the village of Jaslovské Bohunice in the Trnava District of western Slovakia. Bohunice NPP consists of two plants: V1 and V2; both contain two reactor units. The plant was connected to the national power network in stages in the period between 1978 and 1985. The four power reactors are pressurized water reactors of the Soviet VVER-440 design. Annual electricity generation averages about 12,000 GWh. Upon development of

360-456: Is a type of pressurised water reactor (PWR). The main distinguishing features of the VVER compared to other PWRs are: Reactor fuel rods are fully immersed in water kept at (12,5 / 15,7 / 16,2 ) MPa (1812/2277/2349 psi) pressure respectively so that it does not boil at the normal (220 to over 320 °C [428 to >608°F]) operating temperatures. Water in the reactor serves both as a coolant and

396-412: Is designed with redundancy . The secondary circuit also consists of different subsystems: To increase efficiency of the process, steam from the turbine is taken to reheat coolant in the secondary circuit before the deaerator and the steam generator. Water in this circuit is not supposed to be radioactive. The tertiary cooling circuit is an open circuit diverting water from an outside reservoir such as

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432-589: Is planned to be maintained until 2025. In May 2009, Slovak prime minister Robert Fico and Czech PM Jan Fischer announced construction of a new reactor unit at Bohunice. A partnership of JAVYS and the Czech energy company ČEZ will build the plant at a projected cost of around 3.7 billion euros. Specification of the new reactor have not been settled upon but will be rated at between 600 and 1,600 MWe. Four manufacturers have been mooted as possible suppliers: Mitsubishi , Atomenergoprojekt , Westinghouse , and Areva . At

468-553: The Balakovo Nuclear Power Plant . The VVER-1200 (or NPP-2006 or AES-2006) is an evolution of the VVER-1000 being offered for domestic and export use. The reactor design has been refined to optimize fuel efficiency. Specifications include a $ 1,200 per kW overnight construction cost , 54 month planned construction time, and requiring about 35% fewer operational personnel than the VVER-1000. The VVER-1200 has

504-641: The Dukovany NPP to Brno (the second-largest city in the Czech Republic), covering two-thirds of its heat needs. A typical design feature of nuclear reactors is layered safety barriers preventing escape of radioactive material. VVER reactors have three layers: Compared to the RBMK reactors – the type involved in the Chernobyl disaster – the VVER uses an inherently safer design because

540-579: The VVER type instead, which have a higher power output with a more efficient operational process. The A1 power plant was closed and began a decommissioning and cleanup process. As a condition of accession into the European Union in 2004, Slovakia was required to deactivate the two reactors at the V1 plant. A provision in the accession treaty allowed for reactivation in case of an emergency. The V1 plant

576-579: The German regulatory body had already taken the same decision in the wake of the fall of the Berlin Wall . When first built the VVER design was intended to be operational for 35 years. A mid-life major overhaul including a complete replacement of critical parts such as fuel and control rod channels was thought necessary after that. Since RBMK reactors specified a major replacement programme at 35 years designers originally decided this needed to happen in

612-830: The Novovoronezh NPP-II has also been selected for the Seversk, Zentral and South-Urals NPP. A standard version was developed as VVER-1200/513 and based on the VVER-TOI (VVER-1300/510) design. In July 2012 a contract was agreed to build two AES-2006 in Belarus at Ostrovets and for Russia to provide a $ 10 billion loan to cover the project costs. An AES-2006 is being bid for the Hanhikivi Nuclear Power Plant in Finland. The plant supply contract

648-531: The Slovak government ordered the second reactor, then still undergoing a shutdown procedure, to be returned to power-generation-capable mode. The reactor was ultimately not reconnected to the grid, and the final shutdown resumed. Bohunice V2 consists of two second-generation VVER-440/213 units that went online on 20 August 1984 and 18 December 1985, respectively. In November 2010, both reactors were uprated from 440 MW to 505 MW (gross electrical output), and operation

684-751: The VVER have been made: (1 × VVER-1000/446) (2 × VVER-1000/528) (2 × VVER-TOI) (2 × VVER-1200/491 (AES-2006)) (2 × VVER-1000/320) (312+ARK (SUZ) 37) (276+ARK 73) 163 Megawatt Too Many Requests If you report this error to the Wikimedia System Administrators, please include the details below. Request from 172.68.168.226 via cp1108 cp1108, Varnish XID 193461775 Upstream caches: cp1108 int Error: 429, Too Many Requests at Thu, 28 Nov 2024 05:39:30 GMT Bohunice Nuclear Power Plant The Jaslovské Bohunice Nuclear Power Plant (NPP) ( Slovak : Atómové elektrárne Jaslovské Bohunice , abbr. EBO)

720-521: The VVER type as well, although they are of more robust design than the RBMK type. Most of Russia's VVER plants are now reaching and passing the 35 year mark. More recent design studies have allowed for an extension of lifetime up to 50 years with replacement of equipment. New VVERs will be nameplated with the extended lifetime. In 2010 the oldest VVER-1000, at Novovoronezh , was shut down for modernization to extend its operating life for an additional 20 years;

756-548: The VVER-1000 used for the Kudankulam Nuclear Power Plant in India. This has been retained for the newer VVER-1200 and future designs. The system is based on a cooling system and water tanks built on top of the containment dome. The passive systems handle all safety functions for 24 hours, and core safety for 72 hours. Other new safety systems include aircraft crash protection, hydrogen recombiners , and

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792-586: The VVER-1000 with increased power output to about 1200 MWe (gross) and providing additional passive safety features. In 2012, Rosatom stated that in the future it intended to certify the VVER with the British and U.S. regulatory authorities, though was unlikely to apply for a British licence before 2015. The construction of the first VVER-1300 (VVER-TOI) 1300 MWE unit was started in 2018. The Russian abbreviation VVER stands for 'water-water energy reactor' (i.e. water-cooled water-moderated energy reactor). The design

828-790: The VVER-1200 are: The construction of the first two VVER-TOI units was started in 2018 and 2019 at the Kursk II Nuclear Power Plant . In June 2019 the VVER-TOI was certified as compliant with European Utility Requirements (with certain reservations) for nuclear power plants. An upgraded version of AES-2006 with TOI standards, the VVER-1200/513, is being built in Akkuyu Nuclear Power Plant in Turkey. A number of designs for future versions of

864-409: The control rods into the core. As stated above, the water in the primary circuits is kept under a constant elevated pressure to avoid its boiling. Since the water transfers all the heat from the core and is irradiated, the integrity of this circuit is crucial. Four main components can be distinguished: To provide for the continued cooling of the reactor core in emergency situations the primary cooling

900-415: The coolant is also the moderator, and by nature of its design has a negative void coefficient like all PWRs. It does not have the graphite-moderated RBMK's risk of increased reactivity and large power transients in the event of a loss of coolant accident. The RBMK reactors were also constructed without containment structures on grounds of cost due to their size; the VVER core is considerably smaller. One of

936-576: The earliest versions of the VVER-type, the VVER-440 manifested certain problems with its containment building design. As the V-230 and older models were from the outset not built to resist a design-critical large pipe break, the manufacturer added with the newer model V-213 a so called Bubble condenser tower , that – with its additional volume and a number of water layers – aims to suppress the forces of

972-590: The first nuclear power plant in Czechoslovakia. It had one experimental reactor, the KS-150 , designed in Czechoslovakia, which used non-enriched uranium as a fuel. Unlike conventional reactors, refuelling was carried out with the reactor in operation. From the beginning, however, there were many problems with the operation of the reactor, and a number of accidents occurred, related to the reactor's experimental design. The first accident took place in 1976, during

1008-436: The first to undergo such an operating life extension. The work includes the modernization of management, protection and emergency systems, and improvement of security and radiation safety systems. In 2018 Rosatom announced it had developed a thermal annealing technique for reactor pressure vessels which ameliorates radiation damage and extends service life by between 15 and 30 years. This had been demonstrated on unit 1 of

1044-512: The rapidly escaping steam without the onset of a containment-leak. As a consequence, all member-countries with plants of design VVER-440 V-230 and older were forced by the politicians of the European Union to shut them down permanently. Because of this, Bohunice Nuclear Power Plant had to close two reactors and Kozloduy Nuclear Power Plant had to close four. Whereas in the case of the Greifswald Nuclear Power Plant ,

1080-460: The reactor and steam generators this includes an improved refueling machine, and the computerized reactor control systems. Likewise protected in the same building are the emergency systems, including an emergency core cooling system, emergency backup diesel power supply, and backup feed water supply, A passive heat removal system had been added to the existing active systems in the AES-92 version of

1116-414: The replacement of fuel cells , costing the lives of two people. A second major accident, which received a fourth-degree rating by INES , occurred during refuelling on 22 February 1977. A decision was subsequently made to shut down the reactor, due to the high cost of repairs following the accident as well as inefficiency of operation. Czechoslovakia decided to build additional conventional Soviet reactors of

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1152-439: The units is expected between 2026 and 2028. From 2020 an 18-month refuelling cycle will be piloted, resulting in an improved capacity utilisation factor compared to the previous 12-month cycle. The VVER-1200 is designed to be capable of varying power between 100% and 40% for daily load following, which was tested in 2024. The nuclear part of the plant is housed in a single building acting as containment and missile shield. Besides

1188-419: Was developed after 1975 and is a four-loop system housed in a containment -type structure with a spray steam suppression system ( Emergency Core Cooling System ). VVER reactor designs have been elaborated to incorporate automatic control, passive safety and containment systems associated with Western generation III reactors . The VVER-1200 is the version currently offered for construction, being an evolution of

1224-546: Was exempted from the sale of Slovenské Elektrárne to Enel and transferred to the Slovak Nuclear and Decommissioning Company (JAVYS), a national nuclear decommissioning company fully owned by the state. The first reactor was shut down at the end of 2006 and the second on the last day of 2008. The Russia-Ukraine gas dispute in January 2009 disrupted natural gas supplies and electricity generation. On 10 January 2009,

1260-470: Was signed in 2013, but terminated in 2022 mainly due to Russian invasion of Ukraine. From 2015 to 2017 Egypt and Russia came to an agreement for the construction of four VVER-1200 units at El Dabaa Nuclear Power Plant . On 30 November 2017, concrete was poured for the nuclear island basemat for first of two VVER-1200/523 units at the Rooppur Nuclear Power Plant in Bangladesh . The power plant will be

1296-439: Was the most common design, delivering 440 MW of electrical power. The V230 employs six primary coolant loops each with a horizontal steam generator . A modified version of VVER-440, Model V213, was a product of the first nuclear safety standards adopted by Soviet designers. This model includes added emergency core cooling and auxiliary feedwater systems as well as upgraded accident localization systems. The larger VVER-1000

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