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72-554: The Pakistan Atomic Research Reactor or ( PARR ) are two nuclear research reactors and two other experimental neutron sources located in the PINSTECH Laboratory, Nilore , Islamabad , Pakistan. In addition a reprocessing facility referred to as New Labs also exists for nuclear weapons research and production. The first nuclear reactor was supplied and financially constructed by the Government of United States of America in

144-463: A neutron particle and nuclear accelerator to conduct the research of explosions of nuclear elements and isotopes in a nuclear device . Known as a Charged Particle Accelerator (CPA), the nuclear accelerator is a 250 keV Ion accelerator which can deliver all Gaseous ions such as H , N , O , He , Ne , Ar , Kr , Xe or molecular ions . The accelerator's energy range is highly flexible and ions between 50 and 250 keV can be delivered to

216-475: A nuclear proliferation risk as they can be configured to produce plutonium , as well as tritium gas used in boosted fission weapons . Reactor spent fuel can be reprocessed to yield up to 25% more nuclear fuel, which can be used in reactors again. Reprocessing can also significantly reduce the volume of nuclear waste, and has been practiced in Europe, Russia, India and Japan. Due to concerns of proliferation risks,

288-553: A " neutron howitzer ") produced a barium residue, which they reasoned was created by fission of the uranium nuclei. In their second publication on nuclear fission in February 1939, Hahn and Strassmann predicted the existence and liberation of additional neutrons during the fission process, opening the possibility of a nuclear chain reaction . Subsequent studies in early 1939 (one of them by Szilárd and Fermi), revealed that several neutrons were indeed released during fission, making available

360-441: A crucial role in generating large amounts of electricity with low carbon emissions, contributing significantly to the global energy mix. Just as conventional thermal power stations generate electricity by harnessing the thermal energy released from burning fossil fuels , nuclear reactors convert the energy released by controlled nuclear fission into thermal energy for further conversion to mechanical or electrical forms. When

432-445: A gas or a liquid metal (like liquid sodium or lead) or molten salt – is circulated past the reactor core to absorb the heat that it generates. The heat is carried away from the reactor and is then used to generate steam. Most reactor systems employ a cooling system that is physically separated from the water that will be boiled to produce pressurized steam for the turbines , like the pressurized water reactor . However, in some reactors

504-442: A large fissile atomic nucleus such as uranium-235 , uranium-233 , or plutonium-239 absorbs a neutron, it may undergo nuclear fission. The heavy nucleus splits into two or more lighter nuclei, (the fission products ), releasing kinetic energy , gamma radiation , and free neutrons . A portion of these neutrons may be absorbed by other fissile atoms and trigger further fission events, which release more neutrons, and so on. This

576-424: A less effective moderator. In other reactors, the coolant acts as a poison by absorbing neutrons in the same way that the control rods do. In these reactors, power output can be increased by heating the coolant, which makes it a less dense poison. Nuclear reactors generally have automatic and manual systems to scram the reactor in an emergency shut down. These systems insert large amounts of poison (often boron in

648-570: A number of ways: A kilogram of uranium-235 (U-235) converted via nuclear processes releases approximately three million times more energy than a kilogram of coal burned conventionally (7.2 × 10 joules per kilogram of uranium-235 versus 2.4 × 10 joules per kilogram of coal). The fission of one kilogram of uranium-235 releases about 19 billion kilocalories , so the energy released by 1 kg of uranium-235 corresponds to that released by burning 2.7 million kg of coal. A nuclear reactor coolant – usually water but sometimes

720-461: A patent on reactors on 19 December 1944. Its issuance was delayed for 10 years because of wartime secrecy. "World's first nuclear power plant" is the claim made by signs at the site of the EBR-I , which is now a museum near Arco, Idaho . Originally called "Chicago Pile-4", it was carried out under the direction of Walter Zinn for Argonne National Laboratory . This experimental LMFBR operated by

792-737: A pile (hence the name) of graphite blocks, embedded in which was natural uranium oxide 'pseudospheres' or 'briquettes'. Soon after the Chicago Pile, the Metallurgical Laboratory developed a number of nuclear reactors for the Manhattan Project starting in 1943. The primary purpose for the largest reactors (located at the Hanford Site in Washington ), was the mass production of plutonium for nuclear weapons. Fermi and Szilard applied for

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864-407: A planned typical lifetime of 30–40 years, though many of those have received renovations and life extensions of 15–20 years. Some believe nuclear power plants can operate for as long as 80 years or longer with proper maintenance and management. While most components of a nuclear power plant, such as steam generators, are replaced when they reach the end of their useful lifetime, the overall lifetime of

936-471: A reactor. One such process is delayed neutron emission by a number of neutron-rich fission isotopes. These delayed neutrons account for about 0.65% of the total neutrons produced in fission, with the remainder (termed " prompt neutrons ") released immediately upon fission. The fission products which produce delayed neutrons have half-lives for their decay by neutron emission that range from milliseconds to as long as several minutes, and so considerable time

1008-627: A region as the result of only natural processes, with no human intervention Indigenous (band) , an American blues-rock band Indigenous (horse) , a Hong Kong racehorse Indigenous (film) , Australian, 2016 See also [ edit ] Indigenous Australians Indigenous language Indigenous peoples in Canada Indigenous religion Missing and Murdered Indigenous Women Native (disambiguation) All pages with titles beginning with Indigenous All pages with titles containing Indigenous Topics referred to by

1080-518: A set of theoretical nuclear reactor designs. These are generally not expected to be available for commercial use before 2040–2050, although the World Nuclear Association suggested that some might enter commercial operation before 2030. Current reactors in operation around the world are generally considered second- or third-generation systems, with the first-generation systems having been retired some time ago. Research into these reactor types

1152-430: A target of dimensions ranging from few mm to many cm. The particle facility is designed to implantation of Mo , Sn , and Pb ions into steel, friction can be reduced by up to ~50%. During the process of ion implantation, the oxidation is inhibited by suitable ions such as B , Ca into metals. The PINSTECH accelerator can be used by mutual arrangement between PINSTECH and industry or any other organisations. In 1961,

1224-470: Is an under-moderated array with H to U ratio of temperature of 20 °C (68 °F) and provides a strong Negative temperature coefficient and thermal volume coefficients of reactivity . The PAEC scientists and engineers also built and constructed the nuclear accelerator on 9 April 1989. The particle accelerator is heavily used to conduct research in nuclear technology. Unlike the PARR-I and PARR-II

1296-413: Is inserted deeper into the reactor, it absorbs more neutrons than the material it displaces – often the moderator. This action results in fewer neutrons available to cause fission and reduces the reactor's power output. Conversely, extracting the control rod will result in an increase in the rate of fission events and an increase in power. The physics of radioactive decay also affects neutron populations in

1368-428: Is known as a nuclear chain reaction . To control such a nuclear chain reaction, control rods containing neutron poisons and neutron moderators are able to change the portion of neutrons that will go on to cause more fission. Nuclear reactors generally have automatic and manual systems to shut the fission reaction down if monitoring or instrumentation detects unsafe conditions. The reactor core generates heat in

1440-405: Is mined, processed, enriched, used, possibly reprocessed and disposed of is known as the nuclear fuel cycle . Under 1% of the uranium found in nature is the easily fissionable U-235 isotope and as a result most reactor designs require enriched fuel. Enrichment involves increasing the percentage of U-235 and is usually done by means of gaseous diffusion or gas centrifuge . The enriched result

1512-401: Is produced. Fission also produces iodine-135 , which in turn decays (with a half-life of 6.57 hours) to new xenon-135. When the reactor is shut down, iodine-135 continues to decay to xenon-135, making restarting the reactor more difficult for a day or two, as the xenon-135 decays into cesium-135, which is not nearly as poisonous as xenon-135, with a half-life of 9.2 hours. This temporary state is

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1584-448: Is reaching or crossing their design lifetimes of 30 or 40 years. In 2014, Greenpeace warned that the lifetime extension of ageing nuclear power plants amounts to entering a new era of risk. It estimated the current European nuclear liability coverage in average to be too low by a factor of between 100 and 1,000 to cover the likely costs, while at the same time, the likelihood of a serious accident happening in Europe continues to increase as

1656-416: Is required to determine exactly when a reactor reaches the critical point. Keeping the reactor in the zone of chain reactivity where delayed neutrons are necessary to achieve a critical mass state allows mechanical devices or human operators to control a chain reaction in "real time"; otherwise the time between achievement of criticality and nuclear meltdown as a result of an exponential power surge from

1728-463: Is similar to Miniature neutron source reactor (MNSR) and SLOWPOKE reactor . The reactor was indigenously designed by the PAEC as the chairman Munir Ahmad Khan and his team of engineers and scientists also led the construction of the reactor. The PARR-II Reactor had gone critical and began operating on 21 January 1974. The PARR-II Reactor is a tank-in-pool reactor with a rated power of 27–30 kW. Same as

1800-521: Is then converted into uranium dioxide powder, which is pressed and fired into pellet form. These pellets are stacked into tubes which are then sealed and called fuel rods . Many of these fuel rods are used in each nuclear reactor. indigenous [REDACTED] Look up indigenous in Wiktionary, the free dictionary. Indigenous may refer to: Indigenous peoples Indigenous (ecology) , presence in

1872-689: The Atoms for Peace program. The PINSTECH institute was designed by American architect Edward Durrell Stone , when noted Pakistani scientists , Abdus Salam and Ishrat Hussain Usmani travelled to the United States of America in the early 1960s. The first reactor was supplied by the American Machine and Foundry as its contractors, and the first reactor was built by the American nuclear engineer Peter Karter . In

1944-484: The Manhattan Project . Eventually, the first artificial nuclear reactor, Chicago Pile-1 , was constructed at the University of Chicago , by a team led by Italian physicist Enrico Fermi, in late 1942. By this time, the program had been pressured for a year by U.S. entry into the war. The Chicago Pile achieved criticality on 2 December 1942 at 3:25 PM. The reactor support structure was made of wood, which supported

2016-656: The New Labs is not subject to IAEA inspections. and is completely different from its parent reactors. It is a plutonium -fuel reprocessing plant and works as a pilot Pu reprocessing facility with a capability to use the ~7% Pu, to handle the isotopes and use the Kr emissions and radiation . It is also a reprocessing plant to change <~7% Pu into <~7% weapon-grade Pu fuel. New Labs were designed and constructed indigenously by Pakistan Atomic Energy Commission (PAEC) under its chairman Munir Ahmad Khan whereas it project-director

2088-514: The PWR , BWR and PHWR designs above, and some are more radical departures. The former include the advanced boiling water reactor (ABWR), two of which are now operating with others under construction, and the planned passively safe Economic Simplified Boiling Water Reactor (ESBWR) and AP1000 units (see Nuclear Power 2010 Program ). Rolls-Royce aims to sell nuclear reactors for the production of synfuel for aircraft. Generation IV reactors are

2160-515: The U.S. Atomic Energy Commission produced 0.8 kW in a test on 20 December 1951 and 100 kW (electrical) the following day, having a design output of 200 kW (electrical). Besides the military uses of nuclear reactors, there were political reasons to pursue civilian use of atomic energy. U.S. President Dwight Eisenhower made his famous Atoms for Peace speech to the UN General Assembly on 8 December 1953. This diplomacy led to

2232-570: The United States Government led the establishment of ICF -based Fusion power experimental source near at Nilore, before the establishment of PINSTECH Institute. The neutron generator was bought by the PAEC from Texas A&M Nuclear Science Center . The facility is capable of producing mono-energetic neutrons at 3.5–14.7 MeV from deuterium-tritium reaction generated by the Fusion power . This fusion experimental devices has capability to capture

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2304-477: The coolant also acts as a neutron moderator . A moderator increases the power of the reactor by causing the fast neutrons that are released from fission to lose energy and become thermal neutrons. Thermal neutrons are more likely than fast neutrons to cause fission. If the coolant is a moderator, then temperature changes can affect the density of the coolant/moderator and therefore change power output. A higher temperature coolant would be less dense, and therefore

2376-402: The "iodine pit." If the reactor has sufficient extra reactivity capacity, it can be restarted. As the extra xenon-135 is transmuted to xenon-136, which is much less a neutron poison, within a few hours the reactor experiences a "xenon burnoff (power) transient". Control rods must be further inserted to replace the neutron absorption of the lost xenon-135. Failure to properly follow such a procedure

2448-566: The 1986 Chernobyl disaster and 2011 Fukushima disaster . As of 2022 , the International Atomic Energy Agency reported there are 422 nuclear power reactors and 223 nuclear research reactors in operation around the world. The US Department of Energy classes reactors into generations, with the majority of the global fleet being Generation II reactors constructed from the 1960s to 1990s, and Generation IV reactors currently in development. Reactors can also be grouped by

2520-593: The HEU fuel. The reactor was made critical on 31 October 1991 under the supervision of Dr. Ishfaq Ahmad and Dr. Iqbal Hussain Qureshi , and attained power level of 10 MW on 7 May 1992. The core configuration attained its equilibrium configuration in February 1995. The PARR-II Reactor is an indigenously designed and constructed reactor owned by the Pakistan Atomic Energy Commission. The PARR-II Reactor's design

2592-508: The India's Operation Smiling Buddha nuclear test, both British and French consumer companies immediately cancelled their contracts with PAEC. The plant was completed in 1981 and cold reprocessing tests for producing plutonium took place at New Labs in 1986. The New Labs came into limelight when Pakistan had secretly tested its plutonium weapon-based nuclear device in Kirana Hills . On 30 May 1998,

2664-551: The PAEC scientists, under renowned nuclear physicist Dr. Samar Mubarakmand , had tested a miniaturised nuclear device that is believed to be a Plutonium devices for which plutonium was most likely reprocessed by the Pakistani scientists into weapon-grade at the New Labs. The test yield of a nuclear devices was reported to be 12–40  kt . In early 1983, Pakistani nuclear physicist Dr. Samar Mubarakmand developed and established

2736-708: The U.S. military sought other uses for nuclear reactor technology. Research by the Army led to the power stations for Camp Century, Greenland and McMurdo Station, Antarctica Army Nuclear Power Program . The Air Force Nuclear Bomber project resulted in the Molten-Salt Reactor Experiment . The U.S. Navy succeeded when they steamed the USS Nautilus (SSN-571) on nuclear power 17 January 1955. The first commercial nuclear power station, Calder Hall in Sellafield , England

2808-472: The United States does not engage in or encourage reprocessing. Reactors are also used in nuclear propulsion of vehicles. Nuclear marine propulsion of ships and submarines is largely restricted to naval use. Reactors have also been tested for nuclear aircraft propulsion and spacecraft propulsion . Reactor safety is maintained through various systems that control the rate of fission. The insertion of control rods, which absorb neutrons, can rapidly decrease

2880-565: The area was contaminated, like Fukushima, Three Mile Island, Sellafield, and Chernobyl. The British branch of the French concern EDF Energy , for example, extended the operating lives of its Advanced Gas-cooled Reactors (AGR) with only between 3 and 10 years. All seven AGR plants were expected to be shut down in 2022 and in decommissioning by 2028. Hinkley Point B was extended from 40 to 46 years, and closed. The same happened with Hunterston B , also after 46 years. An increasing number of reactors

2952-770: The beginning of his quest to produce the Einstein-Szilárd letter to alert the U.S. government. Shortly after, Nazi Germany invaded Poland in 1939, starting World War II in Europe. The U.S. was not yet officially at war, but in October, when the Einstein-Szilárd letter was delivered to him, Roosevelt commented that the purpose of doing the research was to make sure "the Nazis don't blow us up." The U.S. nuclear project followed, although with some delay as there remained skepticism (some of it from Enrico Fermi ) and also little action from

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3024-458: The choices of coolant and moderator. Almost 90% of global nuclear energy comes from pressurized water reactors and boiling water reactors , which use water as a coolant and moderator. Other designs include heavy water reactors , gas-cooled reactors , and fast breeder reactors , variously optimizing efficiency, safety, and fuel type , enrichment , and burnup . Small modular reactors are also an area of current development. These reactors play

3096-467: The complexities of handling actinides , but significant scientific and technical obstacles remain. Despite research having started in the 1950s, no commercial fusion reactor is expected before 2050. The ITER project is currently leading the effort to harness fusion power. Thermal reactors generally depend on refined and enriched uranium . Some nuclear reactors can operate with a mixture of plutonium and uranium (see MOX ). The process by which uranium ore

3168-660: The dissemination of reactor technology to U.S. institutions and worldwide. The first nuclear power plant built for civil purposes was the AM-1 Obninsk Nuclear Power Plant , launched on 27 June 1954 in the Soviet Union . It produced around 5 MW (electrical). It was built after the F-1 (nuclear reactor) which was the first reactor to go critical in Europe, and was also built by the Soviet Union. After World War II,

3240-485: The energy of the neutrons that sustain the fission chain reaction : In principle, fusion power could be produced by nuclear fusion of elements such as the deuterium isotope of hydrogen . While an ongoing rich research topic since at least the 1940s, no self-sustaining fusion reactor for any purpose has ever been built. Used by thermal reactors: In 2003, the French Commissariat à l'Énergie Atomique (CEA)

3312-638: The first reactor dedicated to peaceful use; in Russia, in 1954, the first small nuclear power reactor APS-1 OBNINSK reached criticality. Other countries followed suit. Heat from nuclear fission is passed to a working fluid coolant (water or gas), which in turn runs through turbines . In commercial reactors, turbines drive electrical generator shafts. The heat can also be used for district heating , and industrial applications including desalination and hydrogen production . Some reactors are used to produce isotopes for medical and industrial use. Reactors pose

3384-507: The first reactor, the reactor is designed to use the High Enrich Uranium (HEU) fuel. The HEU fuel use the ~90% U at a power level of 30 kW. The demineralised light water is used as a coolant moderator and the reactor core is reflected by metallic Be . A PARR-II consists of a core reactor, control rod , and nuclear reflectors, and it is enclosed in a water-tight cylindrical Al alloy vessel. The nuclear reactor core

3456-404: The first stage, reactor building and ancillary facilities were completed with the reactor becoming critical on 21 December 1965. The second stage, consisting of various laboratories, workshop, library and auditorium, became operational in 1974. The facility was last upgraded by PAEC chairman and noted nuclear scientist , Mr. Munir Ahmad Khan in 1989. The PARR-I Reactor was the first reactor that

3528-407: The fission process generates heat, some of which can be converted into usable energy. A common method of harnessing this thermal energy is to use it to boil water to produce pressurized steam which will then drive a steam turbine that turns an alternator and generates electricity. Modern nuclear power plants are typically designed for a lifetime of 60 years, while older reactors were built with

3600-529: The form of boric acid ) into the reactor to shut the fission reaction down if unsafe conditions are detected or anticipated. Most types of reactors are sensitive to a process variously known as xenon poisoning, or the iodine pit . The common fission product Xenon-135 produced in the fission process acts as a neutron poison that absorbs neutrons and therefore tends to shut the reactor down. Xenon-135 accumulation can be controlled by keeping power levels high enough to destroy it by neutron absorption as fast as it

3672-424: The fuel rods. This allows the reactor to be constructed with an excess of fissionable material, which is nevertheless made relatively safe early in the reactor's fuel burn cycle by the presence of the neutron-absorbing material which is later replaced by normally produced long-lived neutron poisons (far longer-lived than xenon-135) which gradually accumulate over the fuel load's operating life. The energy released in

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3744-447: The idea of nuclear fission as a neutron source, since that process was not yet discovered. Szilárd's ideas for nuclear reactors using neutron-mediated nuclear chain reactions in light elements proved unworkable. Inspiration for a new type of reactor using uranium came from the discovery by Otto Hahn , Lise Meitner , and Fritz Strassmann in 1938 that bombardment of uranium with neutrons (provided by an alpha-on-beryllium fusion reaction,

3816-801: The low neutron flux on the order of 10 to 10 neutrons per cm per second, resulting in nucleosynthesis by the s-process ( slow-neutron -capture-process). It is designed and planned to do fast neutron activation for elements such as oxygen and nitrogen as well as some rare earth isotopes. Nuclear reactor technology Nuclear reactors have their origins in the World War II Allied Manhattan Project . The world's first artificial nuclear reactor, Chicago Pile-1, achieved criticality on 2 December 1942. Early reactor designs sought to produce weapons-grade plutonium for fission bombs , later incorporating grid electricity production in addition. In 1957, Shippingport Atomic Power Station became

3888-403: The mid 1960s. The other reactor and reprocessing facility are built and supplied by Pakistan Atomic Energy Commission (PAEC) in the 1970s and 1980s, respectively. Supervised by the United States and International Atomic Energy Agency (IAEA), the first two reactors are subject to IAEA safeguards and its inspections. The PARR-I Reactor was supplied by the United States government in 1965 under

3960-449: The normal nuclear chain reaction, would be too short to allow for intervention. This last stage, where delayed neutrons are no longer required to maintain criticality, is known as the prompt critical point. There is a scale for describing criticality in numerical form, in which bare criticality is known as zero dollars and the prompt critical point is one dollar , and other points in the process interpolated in cents. In some reactors,

4032-581: The opportunity for the nuclear chain reaction that Szilárd had envisioned six years previously. On 2 August 1939, Albert Einstein signed a letter to President Franklin D. Roosevelt (written by Szilárd) suggesting that the discovery of uranium's fission could lead to the development of "extremely powerful bombs of a new type", giving impetus to the study of reactors and fission. Szilárd and Einstein knew each other well and had worked together years previously, but Einstein had never thought about this possibility for nuclear energy until Szilard reported it to him, at

4104-406: The physics of radioactive decay and are simply accounted for during the reactor's operation, while others are mechanisms engineered into the reactor design for a distinct purpose. The fastest method for adjusting levels of fission-inducing neutrons in a reactor is via movement of the control rods . Control rods are made of so-called neutron poisons and therefore absorb neutrons. When a control rod

4176-460: The power plant is limited by the life of components that cannot be replaced when aged by wear and neutron embrittlement , such as the reactor pressure vessel. At the end of their planned life span, plants may get an extension of the operating license for some 20 years and in the US even a "subsequent license renewal" (SLR) for an additional 20 years. Even when a license is extended, it does not guarantee

4248-563: The reactor fleet grows older. The neutron was discovered in 1932 by British physicist James Chadwick . The concept of a nuclear chain reaction brought about by nuclear reactions mediated by neutrons was first realized shortly thereafter, by Hungarian scientist Leó Szilárd , in 1933. He filed a patent for his idea of a simple reactor the following year while working at the Admiralty in London, England. However, Szilárd's idea did not incorporate

4320-416: The reactor will continue to operate, particularly in the face of safety concerns or incident. Many reactors are closed long before their license or design life expired and are decommissioned . The costs for replacements or improvements required for continued safe operation may be so high that they are not cost-effective. Or they may be shut down due to technical failure. Other ones have been shut down because

4392-437: The reactor's output, while other systems automatically shut down the reactor in the event of unsafe conditions. The buildup of neutron-absorbing fission products like xenon-135 can influence reactor behavior, requiring careful management to prevent issues such as the iodine pit , which can complicate reactor restarts. There have been two reactor accidents classed as an International Nuclear Event Scale Level 7 "major accident":

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4464-417: The same term [REDACTED] This disambiguation page lists articles associated with the title Indigenous . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Indigenous&oldid=1257786797 " Category : Disambiguation pages Hidden categories: Short description

4536-637: The small number of officials in the government who were initially charged with moving the project forward. The following year, the U.S. Government received the Frisch–Peierls memorandum from the UK, which stated that the amount of uranium needed for a chain reaction was far lower than had previously been thought. The memorandum was a product of the MAUD Committee , which was working on the UK atomic bomb project, known as Tube Alloys , later to be subsumed within

4608-434: The supervision of Hafeez Qureshi , Dr. M. N. Qazi , Naeem Ahmad Khan and Saleem Rana . The PARR-I Reactor attained its full power on 22 June 1966. In PARR-I, it is virtually impossible to adopt secure the fresh supplies of the HEU fuel. However, to ensure the continuity of the nuclear fuel , PARR-I was converted to use the ~20% Low-enriched uranium (LEU) from the U in October 1991 The nuclear fuel conversion program

4680-424: The water for the steam turbines is boiled directly by the reactor core ; for example the boiling water reactor . The rate of fission reactions within a reactor core can be adjusted by controlling the quantity of neutrons that are able to induce further fission events. Nuclear reactors typically employ several methods of neutron control to adjust the reactor's power output. Some of these methods arise naturally from

4752-476: Was a key step in the Chernobyl disaster . Reactors used in nuclear marine propulsion (especially nuclear submarines ) often cannot be run at continuous power around the clock in the same way that land-based power reactors are normally run, and in addition often need to have a very long core life without refueling . For this reason many designs use highly enriched uranium but incorporate burnable neutron poison in

4824-532: Was a mechanical engineer, Chaudhry Abdul Majeed . The construction of the facility was led by NESPAK. In the 1960s PAEC contracted the project with British Nuclear Fuels (BNFL), and Saint-Gobain Techniques Nouvelles (SGN). PAEC engineers and scientists led the initial design for a large-scale reprocessing plant with a capacity to re-process 100 tons of fuel per year, while BNFL and SGN provided funds, technical assistance, and nuclear fuel. However, after

4896-471: Was led by the PAEC chairman Mr. Munir Ahmad Khan . The reactor was also upgraded from the power level of 5 MW to 10 MW. The program was carried out to meet demands of higher neutron fluxes for experimental research purposes and the isotope production. The upgraded reactor was also made available to compensate for the decrease in neutron flux due to higher concentration of U in the LEU fuel as compared to

4968-781: Was officially started by the Generation ;IV International Forum (GIF) based on eight technology goals. The primary goals being to improve nuclear safety, improve proliferation resistance, minimize waste and natural resource utilization, and to decrease the cost to build and run such plants. Generation V reactors are designs which are theoretically possible, but which are not being actively considered or researched at present. Though some generation V reactors could potentially be built with current or near term technology, they trigger little interest for reasons of economics, practicality, or safety. Controlled nuclear fusion could in principle be used in fusion power plants to produce power without

5040-463: Was opened in 1956 with an initial capacity of 50 MW (later 200 MW). The first portable nuclear reactor "Alco PM-2A" was used to generate electrical power (2 MW) for Camp Century from 1960 to 1963. All commercial power reactors are based on nuclear fission . They generally use uranium and its product plutonium as nuclear fuel , though a thorium fuel cycle is also possible. Fission reactors can be divided roughly into two classes, depending on

5112-470: Was supplied by American Machine and Foundry. Peter Karter had personally supervised the construction of the reactor. The PARR-I is a swimming pool-type and Materials Test Reactor (MTR) type research reactor. Originally based on a designed to use the Highly enriched uranium (HEU) fuel, the HEU fuel use the ~93% enriched in U at a power level of 5 MW . The first reactor went critical on 21 December 1965 under

5184-619: Was the first to refer to "Gen II" types in Nucleonics Week . The first mention of "Gen III" was in 2000, in conjunction with the launch of the Generation IV International Forum (GIF) plans. "Gen IV" was named in 2000, by the United States Department of Energy (DOE), for developing new plant types. More than a dozen advanced reactor designs are in various stages of development. Some are evolutionary from

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