A pressurized water reactor (PWR) is a type of light-water nuclear reactor. PWRs constitute the large majority of the world's nuclear power plants. In a PWR, the primary coolant (water) is pumped under high pressure to the reactor core where it is heated by the energy released by the fission of atoms. The heated, high pressure water then flows to a steam generator, where it transfers its thermal energy to lower pressure water of a secondary system where steam is generated. The steam then drives turbines, which spin an electric generator. In contrast to a boiling water reactor (BWR), pressure in the primary coolant loop prevents the water from boiling within the reactor. All light-water reactors use ordinary water as both coolant and neutron moderator. Most use anywhere from two to four vertically mounted steam generators; VVER reactors use horizontal steam generators.
A nuclear meltdown is a severe nuclear reactor accident that results in core damage from overheating. The term nuclear meltdown is not officially defined by the International Atomic Energy Agency or by the United States Nuclear Regulatory Commission. It has been defined to mean the accidental melting of the core of a nuclear reactor, however, and is in common usage a reference to the core's either complete or partial collapse.
A nuclear power plant (NPP) or atomic power station (APS) is a thermal power station in which the heat source is a nuclear reactor. As is typical of thermal power stations, heat is used to generate steam that drives a steam turbine connected to a generator that produces electricity. As of September 2023, the International Atomic Energy Agency reported there were 410 nuclear power reactors in operation in 32 countries around the world, and 57 nuclear power reactors under construction.
The RBMK is a class of graphite-moderated nuclear power reactor designed and built by the Soviet Union. It is somewhat like a boiling water reactor as water boils in the pressure tubes. It is one of two power reactor types to enter serial production in the Soviet Union during the 1970s, the other being the VVER reactor. The name refers to its design where instead of a large steel pressure vessel surrounding the entire core, the core is surrounded by a cylindrical annular steel tank inside a concrete vault and each fuel assembly is enclosed in an individual 8 cm (inner) diameter pipe. The channels also contain the coolant, and are surrounded by graphite.
The Jaslovské Bohunice Nuclear Power Plant (NPP) is a complex of nuclear reactors situated 2.5 km from the village of Jaslovské Bohunice in the Trnava District in western Slovakia.
The Chernobyl Nuclear Power Plant (ChNPP) is a nuclear power plant undergoing decommissioning. ChNPP is located near the abandoned city of Pripyat in northern Ukraine, 16.5 kilometers (10 mi) northwest of the city of Chernobyl, 16 kilometers (10 mi) from the Belarus–Ukraine border, and about 100 kilometers (62 mi) north of Kyiv. The plant was cooled by an engineered pond, fed by the Pripyat River about 5 kilometers (3 mi) northwest from its juncture with the Dnieper river.
The Paks Nuclear Power Plant is located 5 kilometres (3.1 mi) from the small town of Paks, central Hungary, 100km southwest of Budapest on the shores of the Danube river. It is the first and only operating nuclear power station in Hungary. In 2019, its four reactors produced more than 50% of Hungary's electricity production.
The Biblis Nuclear Power Plant is in the South Hessian municipality of Biblis and consists of two units: unit A with a gross output of 1200 megawatts and unit B with a gross output of 1300 megawatts. Both units are pressurized water reactors. The operator of this power plant is the German RWE Power AG, an electrical utility based in Essen. Unit A began operation on July 16, 1974, and entered commercial service on August 25, 1974; unit B reached criticality on March 25, 1976. Both units now are shut down indefinitely for political reasons (Atomausstieg).
Lubmin is a coastal resort in the German state of Mecklenburg-Vorpommern. Lubmin is situated near Greifswald and on the Bay of Greifswald.
The water-water energetic reactor (WWER), or VVER is a series of pressurized water reactor designs originally developed in the Soviet Union, and now Russia, by OKB Gidropress. 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. The first prototype VVER-210 was built at the Novovoronezh Nuclear Power Plant.
The Belene Nuclear Power Plant is an abandoned nuclear power plant 3 km from Belene and 11 km from Svishtov in Pleven Province, northern Bulgaria, near the Danube River. It was intended to substitute four VVER-440 V230 reactors of the Kozloduy Nuclear Power Plant that were decommissioned as a prerequisite for Bulgaria to join the European Union.
Leningrad Nuclear Power Plant ) is a nuclear power plant located in the town of Sosnovy Bor in Russia's Leningrad Oblast, on the southern shore of the Gulf of Finland, some 70 kilometres (43 mi) to the west of the city centre of Saint Petersburg.
The Mochovce Nuclear Power Plant is a nuclear power plant located between the towns of Nitra and Levice, on the site of the former village of Mochovce, Slovakia. Two up-rated 470 MW reactors plus a 471 MW VVER 440 reactor are presently in operation, with a fourth of the same type under construction. In 2022 it generated almost 7,000 GWh of electricity, the power plant provided approximately 20% of Slovakia's electricity needs.
The Czech Republic operates two nuclear power plants: Temelín and Dukovany. As of 2019 the government intends to increase the share of nuclear electricity production from 30 % to 58 %. To this end, a new reactor is to be constructed at the Dukovany site, which will replace older units by 2035. New capacities are also expected to be added at the Temelín site.
The Tōkai Nuclear Power Plant was Japan's first commercial nuclear power plant. The first unit was built in the early 1960s to the British Magnox design, and generated power from 1966 until it was decommissioned in 1998. A second unit, built at the site in the 1970s, was the first in Japan to produce over 1000 MW of electricity. The site is located in Tokai in the Naka District in Ibaraki Prefecture, Japan and is operated by the Japan Atomic Power Company. The total site area amounts to 0.76 km2 with 0.33 km2, or 43% of it, being green area that the company is working to preserve.
Stendal Nuclear Power Station is a nuclear power station which was never completed. It was located in East Germany, near the city of Arneburg, Stendal in Bezirk Magdeburg, today's Saxony-Anhalt.
Rheinsberg Nuclear Power Station was the second nuclear reactor in East Germany after the Rossendorf Research Reactor, and the first nuclear power reactor in East Germany. It was built close to the city of Rheinsberg on the Stechlinsee. The power station was one of the first generation of demonstration power reactors.
Smolensk Nuclear Power Plant is a nuclear power station in Russia. It is located in the Smolensk region, in Desnogorsk province, approximately 100 kilometres (62 mi) from Smolensk, 115 kilometres (71 mi) from Bryansk and 320 kilometres (200 mi) from Moscow. Smolensk Nuclear Power Plant is the biggest power generating station in the north-western region of the united energy system of the Russian Federation. Smolensk NPP has an outer appearance similar to that of Chernobyl NPP units 3-4, as both are later generation RBMKs.
Slovakia has five operational nuclear reactors, with a combined net power capacity of 2,308 MWe, with a sixth coming on line shortly. Within the EU, Slovakia is one of the pro-nuclear Visegrád Group nations.
The VVER-TOI or WWER-TOI is a generation III+ nuclear power reactor based on VVER technology developed by Rosatom. The VVER-TOI design is intended to improve the competitiveness of Russian VVER technology in international markets. It would use VVER-1300/510 water pressurized reactors constructed to meet modern nuclear and radiation safety requirements.
