| VVER reactor class | |
| Fuel Type: | LEU |
| Thermal: | VVER-210: 760 MWth VVER-365: 1,325 MWth VVER-440: 1,375 MWth VVER-1000: 3,000 MWth VVER-1200: 3,212 MWth VVER-TOI: 3,300 MWth |
| Electric: | VVER-210: 210 MWel VVER-365: 365 MWel VVER-440: 440 MWel VVER-1000: 1,000 MWel VVER-1200: 1,200 MWel VVER-TOI: 1,300 MWel |
| Moderator: | Water |
| Coolant: | Liquid (light water) |
| Control: | Control rods |
| Spectrum: | Thermal |
| Fuel State: | Solid |
| Type: | VVER-210 VVER-365 VVER-440 VVER-1000 VVER-1200 VVER-TOI |
| Type Label: | Reactor types |
| Reactor Line: | VVER |
| Generation: | Generation I reactor Generation II reactor Generation III reactor Generation III+ reactor |
| Concept: | Pressurized water reactor |
| Use: | Generation of electricity |
The water-water energetic reactor (WWER),[1] or VVER (from Russian: водо-водяной энергетический реактор; transliterates as ; water-water power reactor) is a series of pressurized water reactor designs originally developed in the Soviet Union, and now Russia, by OKB Gidropress.[2] The idea of such a reactor was proposed at the Kurchatov Institute by Savely Moiseevich Feinberg. VVER were originally developed before the 1970s, and have been continually updated. As a result, the name VVER is associated with a wide variety of reactor designs spanning from generation I reactors to modern generation III+ reactor designs. Power output ranges from 70 to 1300 MWe, with designs of up to 1700 MWe in development.[3] The first prototype VVER-210 was built at the Novovoronezh Nuclear Power Plant.
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 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.[4]
The larger VVER-1000 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 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.[5] [6]
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 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 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 is low enriched (ca. 2.4–4.4% 235U) uranium dioxide (UO2) 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 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 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 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[7] (12km (07miles) away), Leopoldov (9.5km (05.9miles) away), and Hlohovec (13km (08miles) away), and Temelín NPP (Czech Republic) supplying heat to Týn nad Vltavou away. Plans are made to supply heat from the Dukovany NPP to Brno (the second-largest city in the Czech Republic), covering two-thirds of its heat needs.[8]
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 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.[9]
One of 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 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, 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.[10] Since RBMK reactors specified a major replacement programme at 35 years designers originally decided this needed to happen in 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; 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.[11]
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 the Balakovo Nuclear Power Plant.[12]
The VVER-1200 (or NPP-2006 or AES-2006)[13] is an evolution of the VVER-1000 being offered for domestic and export use.[14] [15] 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, a 60 year design lifetime at 90% capacity factor, and requiring about 35% fewer operational personnel than the VVER-1000. The VVER-1200 has a gross and net thermal efficiency of 37.5% and 34.8%. The VVER 1200 will produce 1,198 MWe of power.[16] [17]
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[18] like the Leningrad-II-design are planned (Kaliningrad and Nizhny Novgorod NPP) and under construction. The type VVER-1200/392M[19] as installed at 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.[20] An AES-2006 is being bid for the Hanhikivi Nuclear Power Plant in Finland.[21] The plant supply contract 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.[22]
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 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.[23]
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 the units is expected between 2026 and 2028.[24]
From 2020 an 18-month refuelling cycle will be piloted, resulting in an improved capacity utilisation factor compared to the previous 12-month cycle.[25] The VVER-1200 is designed to be capable of varying power between 100% and 40% for daily load following, which was tested in 2024.[26]
The nuclear part of the plant is housed in a single building acting as containment and missile shield. Besides 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 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.[27] The passive systems handle all safety functions for 24 hours, and core safety for 72 hours.[13]
Other new safety systems include aircraft crash protection, hydrogen recombiners, and a core catcher to contain the molten reactor core in the event of a severe accident.[15] [20] [28] The core catcher will be deployed in the Rooppur Nuclear Power Plant and El Dabaa Nuclear Power Plant.[29] [30]
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.[31]
The main improvements from 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.[32]
In June 2019 the VVER-TOI was certified as compliant with European Utility Requirements (with certain reservations) for nuclear power plants.[33]
An upgraded version of AES-2006 with TOI standards, the VVER-1200/513, is being built in Akkuyu Nuclear Power Plant in Turkey.[34]
A number of designs for future versions of the VVER have been made:[35]
| Turkey | 36.1444°N 33.5411°W | (4 × VVER-1200/513) (AES-2006 with TOI-Standard) | Under construction.[41] | ||
| Belarus | 54.7611°N 26.0892°W | (2 × VVER-1200/491) | Unit 1 operational since 2020.[42] Unit 2 started operating in May 2023.[43] | ||
| Russia | 52.0911°N 47.9553°W | 4 × VVER-1000/320 (2 × VVER-1000/320) | Units 5 and 6 construction cancelled. To be dismantled.[44] | ||
| Bulgaria | 43.6294°N 25.1867°W | (2 × VVER-1000/466B) | Suspended in 2012.[45] | ||
| Slovakia | 48.4944°N 17.6819°W | 2 × VVER-440/230 2 × VVER-440/213 | Split in two plants, V-1 and V-2 with two reactors each. VVER-440/230 units at V-1 plant closed in 2006 and 2008. | ||
| Iran | 28.8296°N 50.886°W | 1 × VVER-1000/446 (1 × VVER-1000/446) (2 × VVER-1000/528) | A version of the V-392 adapted to the Bushehr site.[46] Unit 2 cancelled by Rosatom in 2007, units 3 and 4 planned. | ||
| Czech Republic | 4 × VVER 440/213 | Upgraded to 510 MW in 2009-2012. Upgrade to 522 MW planned.[47] | |||
| Egypt | 31.0442°N 28.4978°W | (4 × VVER 1200/529) | Under construction.[48] [49] [50] | ||
| Germany | 4 × VVER-440/230 1 × VVER-440/213 (3 × VVER-440/213) | Decommissioned. Unit 6 finished, but never operated. Unit 7 and 8 construction cancelled. | |||
| Russia | 2 × VVER-1000/338 2 × VVER-1000/320 | Construction of unit 4 suspended in 1991 and unit 3 slowed down in 1990. In early 1990s construction of unit 3 restarted and commissioned in 2004. Unit 4 in 2012.[51] | |||
| Finland | 1 × VVER-1200/491 | Postponed indefinitely as of March 2022.[52] Contract terminated in May 2022.[53] | |||
| Khmelnytskyi | Ukraine | 2 × VVER-1000/320 (2 × VVER-1000/392B) | Unit 4 construction cancelled in 2021. Unit 3 planned to be completed with Czech company Škoda JS as VVER-1000 and units 5 and 6 contract signed - Westinghouse AP1000.[54] | ||
| Russia | 2 × VVER-440/230 2 × VVER-440/213 | All units prolonged to 60-year operation lifespan.[55] | |||
| India | 8.1689°N 77.7125°W | 2 × VVER-1000/412 (AES-92) (4 × VVER-1000/412) (AES-92) | Unit 1 operational since 13 July 2013; Unit 2 operational since 10 July 2016.[56] Units 3,4,5 and 6 under construction. | ||
| Bulgaria | 4 × VVER-440/230 2 × VVER-1000 | Older VVER-440/230 units closed 2004-2007. | |||
| Russia | 51.6883°N 35.5733°W | 2 × VVER-TOI (2 × VVER-TOI) | First VVER-TOI. | ||
| Russia | 59.8311°N 29.0597°W | 2 × VVER-1200/491 (AES-2006)(2 × VVER-1200/491 (AES-2006)) | The units are the prototypes of the VVER-1200/491 (AES-2006), unit 1 in commercial operation since october 2018, unit 2 since march 2021. | ||
| Finland | 2 × VVER-440/213 | Western control systems, clearly different containment structures. Later modified for a 530 MW output. | |||
| Armenia | 2 × VVER-440/270 | One reactor was shut down in 1989, unit 2 decommissioning planned in 2026. | |||
| Slovakia | 3 × VVER-440/213 (1 × VVER-440/213) | Units 3 and 4 under construction since 1985, unit 3 commissioned in 2023 and unit 4 is to be commissioned in 2025.[57] | |||
| Russia | 1 x VVER-210 (V-1) 1 x VVER-365 (V-3M) 2 × VVER-440/179 1 × VVER-1000/187 | All units are prototypes. Unit 1 and 2 shutdown. Unit 3 modernised in 2002.[58] | |||
| Russia | 51.265°N 39.2115°W | 2 × VVER-1200/392M (AES-2006) | Unit 1 is the prototype of the VVER-1200/392M (AES-2006), commissioned in 2017, followed by unit 2 in 2019. | ||
| Hungary | 4 × VVER-440/213 (2 × VVER-1200/517) | Two VVER-1200 units under construction.[59] | |||
| Germany | 1 × VVER-70 (V-2) | Unit decommissioned in 1990 | |||
| Ukraine | 2 × VVER-440/213 2 × VVER-1000/320 (2 × VVER-1000/320) | Units 5 and 6 planning suspended in 1990. | |||
| Bangladesh | 24.1131°N 89.0686°W | 2 × VVER- 1200/523 | Units 1 and 2 under construction; planned operational in 2023 and 2024.[60] | ||
| Russia | 47.5993°N 42.3719°W | 4 × VVER-1000/320 | Plant construction suspended in 1990 - unit 1 was nearly 100% completed. Construction restarted in 1999-2000 and unit 1 commissioned in 2001 and unit 4 in 2018.[61] | ||
| Ukraine | 1 × VVER-1000/302 1 × VVER-1000/338 1 × VVER-1000/320 (1 × VVER-1000/320) | Unit 4 construction suspended in 1989 and cancelled in 1991.[62] | |||
| Germany | (4 × VVER-1000/320) | All 4 units construction cancelled in 1991 after Germany reunification.[63] | |||
| Czech Republic | 2 × VVER-1000/320(2 × VVER-1000/320) | Western control systems. Both units upgraded to 1086 MWe and commissioned in 2000 and 2002 respectively, units 3 and 4 (same type) cancelled in 1990 due to change of political regime, only foundation was completed. Units 3 and 4 now planned with a different design. | |||
| China | 34.6869°N 119.4597°W | 2 × VVER-1000/428 (AES-91) 2 × VVER-1000/428M (AES-91) (2 × VVER-1200) | VVER-1200 construction started in May 2021 and February 2022. | ||
| China | 40.3514°N 120.5458°W | (2 × VVER-1200) | Construction on the first reactor commenced in 28 July 2021, with construction starting on the second reactor in 19 May 2022. | ||
| Ukraine | 47.5083°N 34.5844°W | 6 × VVER-1000/320 | Largest nuclear power plant in Europe. |
| Specifications | VVER-210[64] | VVER-365 | VVER-440 | VVER-1000 | VVER-1200 (V-392M)[65] [66] [67] | VVER-1300[68] [69] [70] | |
|---|---|---|---|---|---|---|---|
| Thermal output, MW | 760 | 1325 | 1375 | 3000 | 3212 | 3300 | |
| Efficiency, net % | 25.5 | 25.7 | 29.7 | 31.7 | 35.7[71] | 37.9 | |
| Vapor pressure, in 100 kPa | |||||||
| in front of the turbine | 29.0 | 29.0 | 44.0 | 60.0 | 70.0 | ||
| in the first circuit | 100 | 105 | 125 | 160.0 | 165.1 | 165.2 | |
| Water temperature, °C: | |||||||
| core coolant inlet | 250 | 250 | 269 | 289 | 298.2[72] | 297.2 | |
| core coolant outlet | 269 | 275 | 300 | 319 | 328.6 | 328.8 | |
| Equivalent core diameter, m | 2.88 | 2.88 | 2.88 | 3.12 | — | ||
| Active core height, m | 2.50 | 2.50 | 2.50 | 3.50 | — | 3.73[73] | |
| Outer diameter of fuel rods, mm | 10.2 | 9.1 | 9.1 | 9.1 | 9.1 | 9.1 | |
| Number of fuel rods in assembly | 90 | 126 | 126 | 312 | 312 | 313 | |
| Number of fuel assemblies[74] | 349 (312+ARK (SUZ) 37) | 349(276+ARK 73) | 349 (276+ARK 73), (312+ARK 37) Kola | 151 (109+SUZ 42),163 | 163 | 163 | |
| Uranium loading, tons | 38 | 40 | 42 | 66 | 76-85.5 | 87.3 | |
| Average uranium enrichment, % | 2.0 | 3.0 | 3.5 | 4.26 | 4.69 | ||
| Average fuel burnup, MW · day / kg | 13.0 | 27.0 | 28.6 | 48.4 | 55.5 | ||
| Generation | Name | Model | Country | Power plants |
|---|---|---|---|---|
| I | VVER | V-210 (V-1)[76] | Russia | Novovoronezh 1 (decommissioned) |
| V-70 (V-2)[77] | East Germany | Rheinsberg (KKR) (decommissioned) | ||
| V-365 (V-3M) | Russia | Novovoronezh 2 (decommissioned) | ||
| II | VVER-440 | V-179 | Russia | Novovoronezh 3 (decommissioned) - 4 |
| V-230 | Russia | Kola 1-2 | ||
| East Germany | Greifswald 1-4 (decommissioned) | |||
| Bulgaria | Kozloduy 1-4 (decommissioned) | |||
| Slovakia | Bohunice I 1-2 (decommissioned) | |||
| V-213 | Russia | Kola 3-4 | ||
| East Germany | Greifswald 5 (decommissioned) | |||
| Ukraine | Rivne 1-2 | |||
| Hungary | Paks 1-4 | |||
| Czech Republic | Dukovany 1-4 | |||
| Finland | Loviisa 1-2 | |||
| Slovakia | Bohunice II 1-2 Mochovce 1-2 | |||
| V-213+ | Slovakia | Mochovce 3 Mochovce 4 (under construction) | ||
| V-270 | Armenia | Armenian-1 (decommissioned) Armenian-2 | ||
| III | VVER-1000 | V-187 | Russia | Novovoronezh 5 |
| V-302 | Ukraine | South Ukraine 1 | ||
| V-338 | Ukraine | South Ukraine 2 | ||
| Russia | Kalinin 1-2 | |||
| V-320 | Russia | Balakovo 1-4 Kalinin 3-4 Rostov 1-4 | ||
| Ukraine | Rivne 3-4 Zaporizhzhia 1-6 Khmelnytskyi 1-2 South Ukraine 3 | |||
| Bulgaria | Kozloduy 5-6 | |||
| Czech Republic | Temelin 1-2 | |||
| V-428 | China | Tianwan 1-2 | ||
| V-428M | China | Tianwan 3-4 | ||
| V-412 | India | Kudankulam 1-2 Kudankulam 3-6 (under construction) | ||
| V-446 | Iran | Bushehr 1 | ||
| III+ | VVER-1000 | V-528 | Iran | Bushehr 2 (under construction) |
| VVER-1200 | V-392M | Russia | Novovoronezh II 1-2 | |
| V-491 | Russia | Baltic 1-2 (construction frozen) Leningrad II 1-2 | ||
| Belarus | Belarus 1-2 | |||
| China | Tianwan 7-8 (under construction) Xudabao 3-4 (under construction) | |||
| V-509 | Turkey | Akkuyu 1-4 (under construction) | ||
| V-523 | Bangladesh | Ruppur 1-2 (under construction) | ||
| V-529 | Egypt | El Dabaa 1-4 (under construction) | ||
| VVER-1300 | V-510K | Russia | Kursk II 1-2 (under construction) |