Nuclear reactor

:::: Using lead as the liquid metal provides excellent radiation shielding, and allows for operation at very high temperatures. Also, lead is (mostly) transparent to neutrons, so fewer neutrons are lost in the coolant, and the coolant does not become radioactive. Unlike sodium, lead is mostly inert, so there is less risk of explosion or accident, but such large quantities of lead may be problematic from toxicology and disposal points of view. Often a reactor of this type would use a lead-bismuth eutectic mixture. In this case, the bismuth would present some minor radiation problems, as it is not quite as transparent to neutrons, and can be transmuted to a radioactive isotope more readily than lead. The Russian Alfa class submarine uses a lead-bismuth-cooled fast reactor as its main power plant. ::: Sodium-cooled :::: Most LMFBRs are of this type. The TOPAZ, BN-350 and BN-600 in USSR; Superphénix in France; and Fermi-I in the United States were reactors of this type. The sodium is relatively easy to obtain and work with, and it also manages to actually prevent corrosion on the various reactor parts immersed in it. However, sodium explodes violently when exposed to water, so care must be taken, but such explosions would not be more violent than (for example) a leak of superheated fluid from a pressurized-water reactor. The Monju reactor in Japan suffered a sodium leak in 1995 and could not be restarted until May 2010. The EBR-I, the first reactor to have a core meltdown, in 1955, was also a sodium-cooled reactor. - Pebble-bed reactors (PBR) [moderator: graphite; coolant: helium] :: These use fuel molded into ceramic balls, and then circulate gas through the balls. The result is an efficient, low-maintenance, very safe reactor with inexpensive, standardized fuel. The prototypes were the AVR and the THTR-300 in Germany, which produced up to 308MW of electricity between 1985 and 1989 until it was shut down after experiencing a series of incidents and technical difficulties. The HTR-10 is operating in China, where the HTR-PM is being developed. The HTR-PM is expected to be the first generation IV reactor to enter operation. - Molten-salt reactors (MSR) [moderator: graphite, or none for fast spectrum MSRs; coolant: molten salt mixture] ::These dissolve the fuels in fluoride or chloride salts, or use such salts for coolant. MSRs potentially have many safety features, including the absence of high pressures or highly flammable components in the core. They were initially designed for aircraft propulsion due to their high efficiency and high power density. One prototype, the Molten-Salt Reactor Experiment, was built to confirm the feasibility of the Liquid fluoride thorium reactor, a thermal spectrum reactor which would breed fissile uranium-233 fuel from thorium. - Aqueous homogeneous reactor (AHR) [moderator: high-pressure light or heavy water; coolant: high-pressure light or heavy water] :: These reactors use as fuel soluble nuclear salts (usually uranium sulfate or uranium nitrate) dissolved in water and mixed with the coolant and the moderator. As of April 2006, only five AHRs were in operation. ### Future and developing technologies #### Advanced reactors More than a dozen advanced reactor designs are in various stages of development. Some are evolutionary from 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). - The integral fast reactor (IFR) was built, tested and evaluated during the 1980s and then retired under the Clinton administration in the 1990s due to nuclear non-proliferation policies of the administration. Recycling spent fuel is the core of its design and it therefore produces only a fraction of the waste of current reactors. - The pebble-bed reactor, a high-temperature gas-cooled reactor (HTGCR), is designed so high temperatures reduce power output by Doppler broadening of the fuel's neutron cross-section. It uses ceramic fuels so its safe operating temperatures exceed the power-reduction temperature range. Most designs are cooled by inert helium. Helium is not subject to steam explosions, resists neutron absorption leading to radioactivity, and does not dissolve contaminants that can become radioactive. Typical designs have more layers (up to 7) of passive containment than light water reactors (usually 3). A unique feature that may aid safety is that the fuel balls actually form the core's mechanism, and are replaced one by one as they age. The design of the fuel makes fuel reprocessing expensive. - The small, sealed, transportable, autonomous reactor (SSTAR) is being primarily researched and developed in the US, intended as a fast-breeder reactor that is passively safe and could be remotely shut down in case the suspicion arises that it is being tampered with. - The Clean and Environmentally Safe Advanced Reactor (CAESAR) is a nuclear reactor concept that uses steam as a moderator – this design is in development. - The reduced moderation water reactor builds upon the Advanced boiling water reactor ABWR) that is presently in use. It is not a complete fast reactor instead using mostly epithermal neutrons, which are between thermal and fast neutrons in speed. - The hydrogen-moderated self-regulating nuclear power module (HPM) is a reactor design emanating from the Los Alamos National Laboratory that uses uranium hydride as fuel. - Subcritical reactors are designed to be safer and more stable, but pose a number of engineering and economic difficulties. One example is the energy amplifier. - Thorium-based reactors – It is possible to convert Thorium-232 into U-233 in reactors specially designed for the purpose. In this way, thorium, which is four times more abundant than uranium, can be used to breed U-233 nuclear fuel. U-233 is also believed to have favourable nuclear properties as compared to traditionally used U-235, including better neutron economy and lower production of long lived transuranic waste. - Advanced heavy-water reactor (AHWR) – A proposed heavy-water-moderated nuclear power reactor that will be the next generation design of the PHWR type. Under development in the Bhabha Atomic Research Centre (BARC), India. - KAMINI – A unique reactor using Uranium-233 isotope for fuel. Built in India by BARC and Indira Gandhi Center for Atomic Research (IGCAR). - India is also planning to build fast-breeder reactors using the thorium – Uranium-233 fuel cycle. The FBTR (Fast Breeder Test Reactor) in operation at Kalpakkam (India) uses Plutonium as a fuel and liquid sodium as a coolant. - China, which has control of the Cerro Impacto deposit, has a reactor and hopes to replace coal energy with nuclear energy. Rolls-Royce aims to sell nuclear reactors for the production of synfuel for aircraft. #### Generation IV reactors Generation IV reactors are 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 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. - Gas-cooled fast reactor - Lead-cooled fast reactor - Molten-salt reactor - Sodium-cooled fast reactor - Supercritical water reactor - Very-high-temperature reactor #### Generation V+ reactors 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. - Liquid-core reactor. A closed loop liquid-core nuclear reactor, where the fissile material is molten uranium or uranium solution cooled by a working gas pumped in through holes in the base of the containment vessel. - Gas-core reactor. A closed loop version of the nuclear lightbulb rocket, where the fissile material is gaseous uranium hexafluoride contained in a fused silica vessel. A working gas (such as hydrogen) would flow around this vessel and absorb the UV light produced by the reaction. This reactor design could also function as a rocket engine, as featured in Harry Harrison's 1976 science-fiction novel *Skyfall*. In theory, using UF6 as a working fuel directly (rather than as a stage to one, as is done now) would mean lower processing costs, and very small reactors. In practice, running a reactor at such high power densities would probably produce unmanageable neutron flux, weakening most reactor materials, and therefore as the flux would be similar to that expected in fusion reactors, it would require similar materials to those selected by the International Fusion Materials Irradiation Facility. - Gas core EM reactor. As in the gas core reactor, but with photovoltaic arrays converting the UV light directly to electricity. This approach is similar to the experimentally proved photoelectric effect that would convert the X-rays generated from aneutronic fusion into electricity, by passing the high energy photons through an array of conducting foils to transfer some of their energy to electrons, the energy of the photon is captured electrostatically, similar to a capacitor. Since X-rays can go through far greater material thickness than electrons, many hundreds or thousands of layers are needed to absorb the X-rays. - Fission fragment reactor. A fission fragment reactor is a nuclear reactor that generates electricity by decelerating an ion beam of fission byproducts instead of using nuclear reactions to generate heat. By doing so, it bypasses the Carnot cycle and can achieve efficiencies of up to 90% instead of 40–45% attainable by efficient turbine-driven thermal reactors. The fission fragment ion beam would be passed through a magnetohydrodynamic generator to produce electricity. - Hybrid nuclear fusion. Would use the neutrons emitted by fusion to fission a blanket of fertile material, like U-238 or Th-232 and transmute other reactor's spent nuclear fuel/nuclear waste into relatively more benign isotopes. #### Fusion reactors *Main article: Fusion power* Controlled nuclear fusion could in principle be used in fusion power plants to produce power without 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. ## Nuclear fuel cycle *Main article: Nuclear fuel cycle* 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 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 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. Most BWR and PWR commercial reactors use uranium enriched to about 4% U-235, and some commercial reactors with a high neutron economy do not require the fuel to be enriched at all (that is, they can use natural uranium). According to the International Atomic Energy Agency there are at least 100 research reactors in the world fueled by highly enriched (weapons-grade/90% enrichment) uranium. Theft risk of this fuel (potentially used in the production of a nuclear weapon) has led to campaigns advocating conversion of this type of reactor to low-enrichment uranium (which poses less threat of proliferation). Fissile U-235 and non-fissile but fissionable and fertile U-238 are both used in the fission process. U-235 is fissionable by thermal (i.e. slow-moving) neutrons. A thermal neutron is one which is moving about the same speed as the atoms around it. Since all atoms vibrate proportionally to their absolute temperature, a thermal neutron has the best opportunity to fission U-235 when it is moving at this same vibrational speed. On the other hand, U-238 is more likely to capture a neutron when the neutron is moving very fast. This U-239 atom will soon decay into plutonium-239, which is another fuel. Pu-239 is a viable fuel and must be accounted for even when a highly enriched uranium fuel is used. Plutonium fissions will dominate the U-235 fissions in some reactors, especially after the initial loading of U-235 is spent. Plutonium is fissionable with both fast and thermal neutrons, which make it ideal for either nuclear reactors or nuclear bombs. Most reactor designs in existence are thermal reactors and typically use water as a neutron moderator (moderator means that it slows down the neutron to a thermal speed) and as a coolant. But in a fast-breeder reactor, some other kind of coolant is used which will not moderate or slow the neutrons down much. This enables fast neutrons to dominate, which can effectively be used to constantly replenish the fuel supply. By merely placing cheap unenriched uranium into such a core, the non-fissionable U-238 will be turned into Pu-239, "breeding" fuel. In a thorium fuel cycle, thorium-232 absorbs a neutron in either a fast or thermal reactor. The thorium-233 beta decays to protactinium-233 and then to uranium-233, which in turn is used as fuel. Hence, like uranium-238, thorium-232 is a fertile material. The thorium fuel cycle is considered to be more resistant to nuclear proliferation than uranium or MOX cycles, but has not been widely adopted. ### Fueling of nuclear reactors The amount of energy in the reservoir of nuclear fuel is frequently expressed in terms of "full-power days," which is the number of 24-hour periods (days) a reactor is scheduled for operation at full power output for the generation of heat energy. The number of full-power days in a reactor's operating cycle (between refueling outage times) is related to the amount of fissile uranium-235 (U-235) contained in the fuel assemblies at the beginning of the cycle. A higher percentage of U-235 in the core at the beginning of a cycle will permit the reactor to be run for a greater number of full-power days. At the end of the operating cycle, the fuel in some of the assemblies is "spent", having spent four to six years in the reactor producing power. This spent fuel is discharged and replaced with new (fresh) fuel assemblies. Though considered "spent," these fuel assemblies contain a large quantity of fuel. In practice it is economics that determines the lifetime of nuclear fuel in a reactor. Long before all possible fission has taken place, the reactor is unable to maintain 100%, full output power, and therefore, income for the utility lowers as plant output power lowers. Most nuclear plants operate at a very low profit margin due to operating overhead, mainly regulatory costs, so operating below 100% power is not economically viable for very long. The fraction of the reactor's fuel core replaced during refueling is typically one-third, but depends on how long the plant operates between refueling. Plants typically operate on 18 month refueling cycles, or 24 month refueling cycles. This means that one refueling, replacing only one-third of the fuel, can keep a nuclear reactor at full power for nearly two years. The disposition and storage of this spent fuel is one of the most challenging aspects of the operation of a commercial nuclear power plant. This nuclear waste is highly radioactive and its toxicity presents a danger for thousands of years. After being discharged from the reactor, spent nuclear fuel is transferred to the on-site spent fuel pool. The spent fuel pool is a large pool of water that provides cooling and shielding of the spent nuclear fuel as well as limit radiation exposure to on-site personnel. Once the energy has decayed somewhat (approximately five years), the fuel can be transferred from the fuel pool to dry shielded casks, that can be safely stored for thousands of years. After loading into dry shielded casks, the casks are stored on-site in a specially guarded facility in impervious concrete bunkers. On-site fuel storage facilities are designed to withstand the impact of commercial airliners, with little to no damage to the spent fuel. An average on-site fuel storage facility can hold 30 years of spent fuel in a space smaller than a football field. Not all reactors need to be shut down for refueling; for example, pebble bed reactors, RBMK reactors, molten-salt reactors, Magnox, AGR and CANDU reactors allow fuel to be shifted through the reactor while it is running. In a CANDU reactor, this also allows individual fuel elements to be situated within the reactor core that are best suited to the amount of U-235 in the fuel element. The amount of energy extracted from nuclear fuel is called its burnup, which is expressed in terms of the heat energy produced per initial unit of fuel weight. Burnup is commonly expressed as megawatt days thermal per metric ton of initial heavy metal. ## Nuclear safety *Main article: Nuclear safety* Nuclear safety covers the actions taken to prevent nuclear and radiation accidents and incidents or to limit their consequences. The nuclear power industry has improved the safety and performance of reactors, and has proposed new, safer (but generally untested) reactor designs but there is no guarantee that the reactors will be designed, built and operated correctly. despite multiple warnings by the NRG and the Japanese nuclear safety administration. According to UBS AG, the Fukushima I nuclear accidents have cast doubt on whether even an advanced economy like Japan can master nuclear safety. Catastrophic scenarios involving terrorist attacks are also conceivable. An interdisciplinary team from MIT has estimated that given the expected growth of nuclear power from 2005 to 2055, at least four serious nuclear accidents would be expected in that period. ## Nuclear accidents ::figure[src="https://upload.wikimedia.org/wikipedia/commons/7/7d/Fukushima_I_by_Digital_Globe.jpg" caption="work=The New York Times }}</ref>"] :: Serious, though rare, nuclear and radiation accidents have occurred. These include the Windscale fire (October 1957), the SL-1 accident (1961), the Three Mile Island accident (1979), Chernobyl disaster (April 1986), and the Fukushima Daiichi nuclear disaster (March 2011). the K-27 reactor accident (1968), and the K-431 reactor accident (1985). Nuclear reactors have been launched into Earth orbit at least 34 times. A number of incidents connected with the unmanned nuclear-reactor-powered Soviet RORSAT especially Kosmos 954 radar satellite which resulted in nuclear fuel reentering the Earth's atmosphere from orbit and being dispersed in northern Canada (January 1978). ## Natural nuclear reactors *Main article: Natural nuclear fission reactor* Almost two billion years ago a series of self-sustaining nuclear fission "reactors" self-assembled in the area now known as Oklo in Gabon, West Africa. The conditions at that place and time allowed a natural nuclear fission to occur with circumstances that are similar to the conditions in a constructed nuclear reactor. Fifteen fossil natural fission reactors have so far been found in three separate ore deposits at the Oklo uranium mine in Gabon. First discovered in 1972 by French physicist Francis Perrin, they are collectively known as the Oklo Fossil Reactors. Self-sustaining nuclear fission reactions took place in these reactors approximately 1.5 billion years ago, and ran for a few hundred thousand years, averaging 100 kW of power output during that time. The concept of a natural nuclear reactor was theorized as early as 1956 by Paul Kuroda at the University of Arkansas. Such reactors can no longer form on Earth in its present geologic period. Radioactive decay of formerly more abundant uranium-235 over the time span of hundreds of millions of years has reduced the proportion of this naturally occurring fissile isotope to below the amount required to sustain a chain reaction with only plain water as a moderator. The natural nuclear reactors formed when a uranium-rich mineral deposit became inundated with groundwater that acted as a neutron moderator, and a strong chain reaction took place. The water moderator would boil away as the reaction increased, slowing it back down again and preventing a meltdown. The fission reaction was sustained for hundreds of thousands of years, cycling on the order of hours to a few days. These natural reactors are extensively studied by scientists interested in geologic radioactive waste disposal. They offer a case study of how radioactive isotopes migrate through the Earth's crust. This is a significant area of controversy as opponents of geologic waste disposal fear that isotopes from stored waste could end up in water supplies or be carried into the environment. ## Emissions Nuclear reactors produce tritium as part of normal operations, which is eventually released into the environment in trace quantities. As an isotope of hydrogen, tritium (T) frequently binds to oxygen and forms T2O. This molecule is chemically identical to H2O and so is both colorless and odorless, however the additional neutrons in the hydrogen nuclei cause the tritium to undergo beta decay with a half-life of 12.3 years. Despite being measurable, the tritium released by nuclear power plants is minimal. The United States NRC estimates that a person drinking water for one year out of a well contaminated by what they would consider to be a significant tritiated water spill would receive a radiation dose of 0.3 millirem. For comparison, this is an order of magnitude less than the 4 millirem a person receives on a round trip flight from Washington, D.C. to Los Angeles, a consequence of less atmospheric protection against highly energetic cosmic rays at high altitudes. The amounts of strontium-90 released from nuclear power plants under normal operations is so low as to be undetectable above natural background radiation. Detectable strontium-90 in ground water and the general environment can be traced to weapons testing that occurred during the mid-20th century (accounting for 99% of the Strontium-90 in the environment) and the Chernobyl accident (accounting for the remaining 1%). ## Notes ## References ## References 1. (2024-05-20). ["Nuclear Fuel Cycle Overview"](https://world-nuclear.org/information-library/nuclear-fuel-cycle/introduction/nuclear-fuel-cycle-overview). 2. Science and Mathematics Education Research Group, University of British Columbia. ["Physics Nuclear Physics: Nuclear Reactors"](https://scienceres-edcp-educ.sites.olt.ubc.ca/files/2015/01/sec_phys_nuclear_reactors.pdf). 3. (2014). "Oklo reactors and implications for nuclear science". *International Journal of Modern Physics E*. 4. [http://www.neimagazine.com/features/featureobninsk-number-one Nuclear Engineering International: Obninsk - number one, by Lev Kotchetkov] {{Webarchive. [link](https://web.archive.org/web/20131102021944/http://www.neimagazine.com/features/featureobninsk-number-one). (2 November 2013, who was there at the time. Source for most of the information in this article.) 5. ["Spent Fuel Reprocessing Options"](https://www-pub.iaea.org/MTCD/publications/PDF/te_1587_web.pdf). *IAEA*. 6. ["PRIS – Home"](https://pris.iaea.org/pris/). 7. ["RRDB Search"](https://nucleus.iaea.org/RRDB/RR/ReactorSearch.aspx?rf=1). 8. Oldekop, W.. (1982). ["Electricity and Heat from Thermal Nuclear Reactors"](http://dx.doi.org/10.1007/978-3-642-68444-9_5). *Springer Berlin Heidelberg*. 9. (2023-02-15). ["Nuclear-Powered Ships"](https://world-nuclear.org/information-library/non-power-nuclear-applications/transport/nuclear-powered-ships). 10. (2025-01-06). ["Nuclear Power in the World Today"](https://world-nuclear.org/information-library/current-and-future-generation/nuclear-power-in-the-world-today). 11. Ambrose, Jillian. (2024-05-07). ["Renewable energy passes 30% of world's electricity supply"](https://www.theguardian.com/environment/article/2024/may/08/renewable-energy-passes-30-of-worlds-electricity-supply). 12. IAEA. (2024-08-29). ["In Operation & Suspended Operation"](https://pris.iaea.org/PRIS/WorldStatistics/OperationalReactorsByType.aspx). 13. ["Manhattan Project: Piles and Plutonium, 1939-1942"](https://www.osti.gov/opennet/manhattan-project-history/Events/1939-1942/piles_plutonium.htm?utm_source=chatgpt.com). 14. ["Manhattan Project: CP-1 Goes Critical, Met Lab, December 2, 1942"](https://www.osti.gov/opennet/manhattan-project-history/Events/1942-1944_pu/cp-1_critical.htm?utm_source=chatgpt.com). 15. ["10 Intriguing Facts About the World's First Nuclear Chain Reaction"](https://www.energy.gov/ne/articles/10-intriguing-facts-about-worlds-first-nuclear-chain-reaction). 16. chm_admin. (2017-12-01). ["A Quiet Start to the Atomic Age"](https://www.chicagohistory.org/nuclear75/). 17. ["Manhattan Project: Places > Metallurgical Laboratory > CP-1 (CHICAGO PILE #1)"](https://www.osti.gov/opennet/manhattan-project-history/Places/MetLab/cp1.html?utm_source=chatgpt.com). 18. ["Reactor Protection & Engineered Safety Feature Systems"](http://www.nucleartourist.com/systems/rp.htm). *The Nuclear Tourist*. 19. ["Bioenergy Conversion Factors"](http://bioenergy.ornl.gov/papers/misc/energy_conv.html). *Bioenergy.ornl.gov*. 20. Bernstein, Jeremy. (2008). ["Nuclear Weapons: What You Need to Know"](https://archive.org/details/nuclearweaponswh0000bern/page/312). *[[Cambridge University Press]]*. 21. (9 October 2000). ["How nuclear power works"](http://science.howstuffworks.com/nuclear-power3.htm). *HowStuffWorks.com*. 22. ["Reactor Protection & Engineered Safety Feature Systems"](http://www.nucleartourist.com/systems/rp.htm). *The Nuclear Tourist*. 23. ["Chernobyl: what happened and why? by CM Meyer, technical journalist."](http://www.eepublishers.co.za/images/upload/Meyer%20Chernobyl%205.pdf). 24. (2011). "Nuclear Energy Encyclopedia: Science, Technology, and Applications". *Wiley*. 25. ["PRIS – Miscellaneous reports – Operational by Age"](https://pris.iaea.org/PRIS/WorldStatistics/OperationalByAge.aspx). 26. [https://www.scientificamerican.com/article/nuclear-power-plant-aging-reactor-replacement-/ ''How Long Can a Nuclear Reactor Last?''] {{Webarchive. [link](https://web.archive.org/web/20170202073144/http://www.scientificamerican.com/article/nuclear-power-plant-aging-reactor-replacement-/). (2 February 2017 Paul Voosen, Scientific American, 20 Nov 2009) 27. [https://www.nrc.gov/reactors/operating/licensing/renewal/subsequent-license-renewal.html ''Status of Subsequent License Renewal Applications.''] {{Webarchive. [link](https://web.archive.org/web/20180121051705/https://www.nrc.gov/reactors/operating/licensing/renewal/subsequent-license-renewal.html). (21 January 2018 NRC, 24 Feb 2022) 28. [https://www.energy.gov/ne/articles/whats-lifespan-nuclear-reactor-much-longer-you-might-think ''What's the Lifespan for a Nuclear Reactor? Much Longer Than You Might Think''] {{Webarchive. [link](https://web.archive.org/web/20200609230342/https://www.energy.gov/ne/articles/whats-lifespan-nuclear-reactor-much-longer-you-might-think). (9 June 2020 . Office of Nuclear Energy, 16 Apr 2020) 29. (2006-08-05). ["Swedish nuclear reactors shut down over safety concerns"](https://en.wikinews.org/wiki/Swedish_nuclear_reactors_shut_down_over_safety_concerns). *Wikinews*. 30. [https://saplnh.org/about-nuclear/nuclear-plant-lifespans/ ''The True Lifespan of a Nuclear Power Plant''] {{Webarchive. [link](https://web.archive.org/web/20230219095448/https://saplnh.org/about-nuclear/nuclear-plant-lifespans/). (19 February 2023 . Seacoast Anti-Pollution League (SAPL), 2017) 31. IAEA. "Cleanup of Large Areas Contaminated as a Result of a Nuclear Accident". 32. [https://www.edfenergy.com/energy/nuclear-lifetime-management ''Extending the operating lives of Advanced Gas-cooled Reactors''] {{Webarchive. [link](https://web.archive.org/web/20230219093947/https://www.edfenergy.com/energy/nuclear-lifetime-management). (19 February 2023 . EDF Energy) 33. [https://www.edfenergy.com/about/nuclear/decommissioning ''Nuclear decommissioning''] {{Webarchive. [link](https://web.archive.org/web/20230219093959/https://www.edfenergy.com/about/nuclear/decommissioning). (19 February 2023 . EDF (accessed Feb 2023)) 34. [https://www.greenpeace.org/static/planet4-netherlands-stateless/2018/06/Briefing-Lifetime-extension-of-ageing-nuclear-power-plants.pdf ''Lifetime extension of ageing nuclear power plants: Entering a new era of risk.''] {{Webarchive. [link](https://web.archive.org/web/20230315082620/https://www.greenpeace.org/static/planet4-netherlands-stateless/2018/06/Briefing-Lifetime-extension-of-ageing-nuclear-power-plants.pdf). (15 March 2023 Greenpeace, March, 2014 (2.6&nbsp;MB). [https://inis.iaea.org/search/search.aspx?orig_q=RN:46030160 In German]) 35. [link](https://web.archive.org/web/20080621120547/http://v3.espacenet.com/textdoc?DB=EPODOC). (21 June 2008. British patent number: GB630726 (filed: 28 June 1934; published: 30 March 1936).) 36. The First Reactor, U.S. Atomic Energy Commission, Division of Technical Information 37. Enrico, Fermi and Leo, Szilard {{US Patent. 2708656 "Neutronic Reactor" issued 17 May 1955 38. ["Chicago Pile reactors create enduring research legacy – Argonne's Historical News Releases"](http://www.ne.anl.gov/About/hn/news960320.shtml). *anl.gov*. 39. [https://inlportal.inl.gov/portal/server.pt/gateway/PTARGS_0_200_816_259_0_43/http%3B/inlpublisher%3B7087/publishedcontent/publish/communities/inl_gov/about_inl/home_page_fact_sheets/sheets/experimental_breeder_reactor___i_4.pdf Experimental Breeder Reactor 1 factsheet], Idaho National Laboratory {{webarchive. [link](https://web.archive.org/web/20081029200744/https://inlportal.inl.gov/portal/server.pt/gateway/PTARGS_0_200_816_259_0_43/http%3B/inlpublisher%3B7087/publishedcontent/publish/communities/inl_gov/about_inl/home_page_fact_sheets/sheets/experimental_breeder_reactor___i_4.pdf). (29 October 2008) 40. (November 2001). ["Fifty years ago in December: Atomic reactor EBR-I produced first electricity"](http://www.ans.org/pubs/magazines/nn/docs/2001-11-2.pdf). *American Nuclear Society Nuclear news*. 41. (11 January 2017). ["The Nuclear Option — NOVA"](https://www.pbs.org/wgbh/nova/video/the-nuclear-option/). 42. Kragh, Helge. (1999). ["Quantum Generations: A History of Physics in the Twentieth Century"](https://archive.org/details/quantumgeneratio0000krag). *Princeton University Press*. 43. (17 October 1956). ["On This Day: 17&nbsp;October"](https://news.bbc.co.uk/onthisday/hi/dates/stories/october/17/newsid_3147000/3147145.stm). *BBC News*. 44. Leskovitz, Frank J.. ["Science Leads the Way"](http://gombessa.tripod.com/scienceleadstheway/id9.html). *Camp Century, Greenland*. 45. Reed, Bruce Cameron. (2020). "Manhattan Project". *Springer International Publishing*. 46. Reed, B. Cameron. (2021). "An inter-country comparison of nuclear pile development during World War II". *The European Physical Journal H*. 47. (1993-08-01). "Nuclear reactors built, being built, or planned 1993". *Office of Scientific and Technical Information (OSTI)*. 48. ["Manhattan Project: Places > Metallurgical Laboratory > CP-2 and CP-3"](https://www.osti.gov/opennet/manhattan-project-history/Places/MetLab/cp2-3.html). 49. (1993-08-01). "Nuclear reactors built, being built, or planned 1993". *Office of Scientific and Technical Information (OSTI)*. 50. (1920-06-03). ["Timeline"](https://ahf.nuclearmuseum.org/ahf/nuc-history/timeline/). 51. Reed, B. Cameron. (2021). "An inter-country comparison of nuclear pile development during World War II". *The European Physical Journal H*. 52. (2014-05-28). ["Discussion Regarding Aqueous Homogeneous Reactor (AHR) Benchmarks"](https://www.osti.gov/servlets/purl/1133322). 53. (1994-09-30). ["Plutonium: The First 50 Years"](https://sgp.fas.org/othergov/doe/pu50yc.html). 54. (2021-12-03). "Critical Assemblies: Dragon Burst Assembly and Solution Assemblies". *Nuclear Technology*. 55. ["ZEEP -- Canada's First Nuclear Reactor"](http://www.sciencetech.technomuses.ca/english/whatson/zeep.cfm). *Canada Science and Technology Museum*. 56. (2023-03-09). ["Oh, My Darling Clementine: A Detailed History and Data Repository of the Los Alamos Plutonium Fast Reactor"](https://digitalscholarship.unlv.edu/context/college_of_sciences_graduate_student_research/article/1000/viewcontent/Oh_My_Darling_Clementine_A_Detailed_History_and_Data_Repository_of_the_Los_Alamos_Plutonium_Fast_Reactor_2___Hannah_Patenaude.pdf). *Informa UK Limited*. 57. Hurst, D.G.. (1997). ["Canada Enters the Nuclear Age: A Technical History of Atomic Energy of Canada Limited as Seen from Its Research Laboratories"](https://books.google.com/books?id=3uz0AwAAQBAJ). *McGill-Queen's University Press*. 58. Hill, C. (2013). "An Atomic Empire: A Technical History of the Rise and Fall of the British Atomic Energy Programme". *Imperial College Press*. 59. Diakov, Anatoli. (2011-04-25). "The History of Plutonium Production in Russia". *Science & Global Security*. 60. (2023-07-03). ["Magnox BEPO reactor 75th Anniversary"](https://www.gov.uk/government/news/magnox-bepo-reactor-75th-anniversary). 61. ["Irène and Frédéric Joliot-Curie"](http://www.curie.fr/fondation/musee/irene-frederic-joliot-curie.cfm/lang/_gb.htm). *Institut Curie*. 62. ["ФКБН / Сводный указатель объектов / Атомный проект СССР // Электронная библиотека /// История Росатома"](https://elib.biblioatom.ru/soviet-atomic-program/objects/fizicheskiy_kotel_na_byistryih_neytronah@13272/). 63. (1999). "Heavy water reactors and nuclear power plants in the USSR and Russia: Past, present, and future". *Atomic Energy*. 64. Reed, Bruce Cameron. (2020). "Manhattan Project". *Springer International Publishing*. 65. (1955-05-01). ["Shippingport"](https://world-nuclear.org/nuclear-reactor-database/details/SHIPPINGPORT). 66. ["ZEEP -- Canada's First Nuclear Reactor"](http://www.sciencetech.technomuses.ca/english/whatson/zeep.cfm). *Canada Science and Technology Museum*. 67. (1958-01-01). ["Rolphton NPD"](https://world-nuclear.org/nuclear-reactor-database/details/Rolphton-NPD). 68. Vakhroucheva, Elizaveta. ["Division of System Analysis Elektronika Information and Computer Complex Engineering and Production Division"](http://www.nti.org/db/nisprofs/russia/reactor/research/with/kurchato.htm#f1). *NTI*. 69. (1951-01-01). ["APS 1 Obninsk"](https://world-nuclear.org/nuclear-reactor-database/details/APS-1-Obninsk). 70. Hill, C. (2013). "An Atomic Empire: A Technical History of the Rise and Fall of the British Atomic Energy Programme". *Imperial College Press*. 71. (1953-08-01). ["Calder Hall 1"](https://world-nuclear.org/nuclear-reactor-database/details/Calder-Hall-1). 72. ["Irène and Frédéric Joliot-Curie"](http://www.curie.fr/fondation/musee/irene-frederic-joliot-curie.cfm/lang/_gb.htm). *Institut Curie*. 73. (1955-03-01). ["G 2 (Marcoule)"](https://world-nuclear.org/nuclear-reactor-database/details/G-2-(Marcoule)). 74. Splunter, J.M. van.. (1994). ["Love at first sight. Co-operation between the Netherlands and Norway on the peaceful use of atomic energy, 1950-1960"](https://inis.iaea.org/search/search.aspx?orig_q=RN:26038487). 75. Blomstrand, Edward. (2005-02-01). ["Swedish nuclear power. A review of the legislation in the nuclear energy field from the second world war til the new millennium; Svensk kaernenergi. En expose oever lagstiftningen paa kaernenergiomraadet fraan andra vaerldskriget till millennieskiftet"](https://www.osti.gov/etdeweb/biblio/20637474). 76. (1957-12-01). ["Agesta"](https://world-nuclear.org/nuclear-reactor-database/details/Agesta). 77. Domain, Research. (2016-04-25). ["Belgian Reactor 1 / Research facilities / Science Platform"](http://science.sckcen.be/en/Facilities/BR1). 78. (1957-11-01). ["BR-3"](https://world-nuclear.org/nuclear-reactor-database/details/BR-3). 79. ["Apsara Research Reactor"](http://www.nti.org/facilities/818/). 80. (1964-10-01). ["Tarapur 1"](https://world-nuclear.org/nuclear-reactor-database/details/Tarapur-1). 81. Trischler, Helmuth. (2004-12-31). "Politik und Kultur im föderativen Staat 1949 bis 1973". *OLDENBOURG WISSENSCHAFTSVERLAG*. 82. (1958-07-01). ["VAK Kahl"](https://world-nuclear.org/nuclear-reactor-database/details/VAK-Kahl). 83. (1955-04-18). ["Die Geschichte des HZDR im Überblick"](https://www.hzdr.de/db/Cms?pOid=26670&pNid=1826). 84. (1960-01-01). ["Rheinsberg"](https://world-nuclear.org/nuclear-reactor-database/details/RHEINSBERG). 85. Frank, Lewis A.. (1966). "Nuclear Weapons Development in China". *Bulletin of the Atomic Scientists*. 86. (1985-03-20). ["Qinshan 1"](https://world-nuclear.org/nuclear-reactor-database/details/Qinshan-1). 87. (18 July 2022). ["Scorie a riposo. ISPRA-1, il primo reattore nucleare italiano {{!}} Il Bo Live UniPD"](https://ilbolive.unipd.it/it/news/societa/scorie-riposo-ispra1-primo-reattore-nucleare). 88. ["Nuclear Power Reactors in the World – 2015 Edition"](http://www-pub.iaea.org/MTCD/Publications/PDF/rds2-35web-85937611.pdf). *International Atomic Energy Agency (IAEA)*. 89. (1993). "Fast-reactor actinoid transmutation". *Atomic Energy*. 90. ["Light Water Nuclear Reactors"](http://hyperphysics.phy-astr.gsu.edu/hbase/NucEne/ligwat.html). *Georgia State University*. 91. Joyce, Malcolm. (2018). "Nuclear Engineering". *Elsevier*. 92. ["Nuclear Energy and Society"](http://www.umich.edu/~gs265/society/nuclear.htm). *University of Michigan*. 93. ["Pool Reactors 1: An Introduction – ANS / Nuclear Newswire"](https://www.ans.org/news/article-2066/pool-reactors-1-an-introduction/). 94. (2018-05-24). "Emergency and Back-Up Cooling of Nuclear Fuel and Reactors and Fire-Extinguishing, Explosion Prevention Using Liquid Nitrogen.". *USPTO Patent Applications*. 95. (8 February 2017). ["Russia completes world's first Gen III+ reactor; China to start up five reactors in 2017"](https://analysis.nuclearenergyinsider.com/russia-completes-worlds-first-gen-iii-reactor-china-start-five-reactors-2017). 96. ''Nucleonics Week'', Vol. 44, No. 39; p. 7, 25 September 2003 Quote: "Etienne Pochon, CEA director of nuclear industry support, outlined EPR's improved performance and enhanced safety features compared to the advanced Generation II designs on which it was based." 97. ["Generation IV"](http://www.euronuclear.org/info/generation-IV.htm). *Euronuclear.org*. 98. Broeders, C. H. M. (2000-12-01). ["Burning transuranium isotopes in thermal and fast reactors"](https://www.sciencedirect.com/science/article/pii/S0029549300003411). *Nuclear Engineering and Design*. 99. Swickard, E.O.. (June 1959). ["Los Alamos Molten Plutonium Reactor Experiment (LAMPRE) Hazard Report"](https://www.osti.gov/servlets/purl/4206527). 100. ["A Technology Roadmap for Generation IV Nuclear Energy Systems"](http://www.gen-4.org/PDFs/GenIVRoadmap.pdf). 101. ["World Nuclear Association Information Brief – Research Reactors"](http://www.world-nuclear.org/info/inf61.htm). 102. ["NUCLEAR 101: How Does a Nuclear Reactor Work?"](https://www.energy.gov/ne/articles/nuclear-101-how-does-nuclear-reactor-work). 103. Jacquemain, Didier. (2015). ["Nuclear power reactor core melt accidents: current state of knowledge"](https://www.edp-open.org/images/stories/books/fulldl/Nuclear_Power_Reactor_Core_Melt_Accidents.pdf). *EDP sciences*. 104. <!-- not stated -->. (2025). ["Nuclear Power Reactors in the World"](https://www-pub.iaea.org/MTCD/Publications/PDF/RDS-2-45_web.pdf). *IAEA [[International Atomic Energy Agency]]*. 105. ["Fact Sheet on U.S. Nuclear Powered Warship (NPW) Safety"](https://www.mofa.go.jp/region/n-america/us/security/fact0604.pdf). 106. ["HTR-PM: Making dreams come true"](https://www.neimagazine.com/features/featurehtr-pm-making-dreams-come-true-7009889/). *Nuclear Engineering International*. 107. ["RRDB Search"](https://nucleus.iaea.org/RRDB/RR/ReactorSearch.aspx). 108. ["Advanced Nuclear Power Reactors"](http://world-nuclear.org/info/inf08.html). *[[World Nuclear Association]]*. 109. Till, Charles. ["Nuclear Reaction: Why Do Americans Fear Nuclear Power?"](https://www.pbs.org/wgbh/pages/frontline/shows/reaction/interviews/till.html). *Public Broadcasting Service (PBS)*. 110. (October 2009). ["High Efficiency Nuclear Power Plants Using Liquid Fluoride Thorium Reactor Technology"](https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20090038711.pdf). *NASA Technical Memorandum*. 111. (14 January 2019). ["The Venezuela-China relationship, explained: Belt and Road {{!}} Part 2 of 4"](https://supchina.com/2019/01/14/venezuela-china-explained-2/). 112. ["Rolls-Royce Touts Nuclear Reactors as Key to Clean Jet Fuel"](https://www.bloomberg.com/amp/news/articles/2019-12-06/rolls-royce-pitches-nuclear-reactors-as-key-to-clean-jet-fuel). 113. De Clercq, Geert. (October 13, 2014). ["Can Sodium Save Nuclear Power?"](https://www.scientificamerican.com/article/can-sodium-save-nuclear-power/). 114. [https://world-nuclear.org/information-library/nuclear-fuel-cycle/nuclear-power-reactors/generation-iv-nuclear-reactors.aspx ''Generation IV Nuclear Reactors''] {{Webarchive. [link](https://web.archive.org/web/20230330074852/https://www.world-nuclear.org/information-library/nuclear-fuel-cycle/nuclear-power-reactors/generation-iv-nuclear-reactors.aspx). (30 March 2023 . World Nuclear Association, update Dec 2020) 115. ["Generation IV Nuclear Reactors"](http://world-nuclear.org/info/inf77.html). *[[World Nuclear Association]]*. 116. ["International Scientific Journal for Alternative Energy and Ecology, DIRECT CONVERSION OF NUCLEAR ENERGY TO ELECTRICITY, Mark A. Prelas"](http://isjaee.hydrogen.ru/pdf/AEE04-07_Prelas.pdf). 117. Quimby, D.C., High Thermal Efficiency X-ray energy conversion scheme for advanced fusion reactors, ASTM Special technical Publication, v.2, 1977, pp. 1161–1165 118. (7 June 2006). ["Improving Security at World's Nuclear Research Reactors: Technical and Other Issues Focus of June Symposium in Norway"](http://www.iaea.org/NewsCenter/News/2006/heu_symposium.html). *IAEA*. 119. (May 2005). ["TECDOC-1450: Thorium fuel cycle — Potential benefits and challenges"](https://www-pub.iaea.org/MTCD/Publications/PDF/TE_1450_web.pdf). 120. Gusterson, Hugh. (16 March 2011). ["The lessons of Fukushima"](http://www.thebulletin.org/web-edition/columnists/hugh-gusterson/the-lessons-of-fukushima). *Bulletin of the Atomic Scientists*. 121. Paton, James. (4 April 2011). ["Fukushima Crisis Worse for Atomic Power Than Chernobyl, UBS Says"](http://www.businessweek.com/news/2011-04-04/fukushima-crisis-worse-for-atomic-power-than-chernobyl-ubs-says.html). *Bloomberg Businessweek*. 122. (December 2015). ["Providing all Global Energy with Wind, Water, and Solar Power, Part I: Technologies, Energy Resources, Quantities and Areas of Infrastructure, and Materials"](http://www.stanford.edu/group/efmh/jacobson/Articles/I/WWSEnergyPolicyPtI.pdf). *Energy Policy*. 123. Massachusetts Institute of Technology. (2003). ["The Future of Nuclear Power"](http://web.mit.edu/nuclearpower/pdf/nuclearpower-full.pdf). 124. Fackler, Martin. (1 June 2011). ["Report Finds Japan Underestimated Tsunami Danger"](https://www.nytimes.com/2011/06/02/world/asia/02japan.html?_r=1&ref=world). *The New York Times*. 125. [[Nuclear-powered submarine]] mishaps include the [[Soviet submarine K-19. [link](https://web.archive.org/web/20150111213912/http://www.iaea.org/Publications/Magazines/Bulletin/Bull413/article1.pdf). (11 January 2015 p. 14.) 126. Johnston, Robert. (23 September 2007). ["Deadliest radiation accidents and other events causing radiation casualties"](http://www.johnstonsarchive.net/nuclear/radevents/radevents1.html). *Database of Radiological Incidents and Related Events*. 127. [https://web.archive.org/web/20090328130544/http://www.time.com/time/photogallery/0,29307,1887705,00.html The Worst Nuclear Disasters]. ''Time''. 128. [link](https://web.archive.org/web/20060804021811/http://video.google.com/videoplay?docid=-2334857802602777622). (4 August 2006) 129. Meshik, Alex P. (November 2005) [http://www.scientificamerican.com/article/ancient-nuclear-reactor/ "The Workings of an Ancient Nuclear Reactor."] {{Webarchive. [link](https://web.archive.org/web/20150315120003/http://www.scientificamerican.com/article/ancient-nuclear-reactor/). (15 March 2015 ''Scientific American.'' p. 82.) 130. ["Oklo: Natural Nuclear Reactors"](http://www.ocrwm.doe.gov/factsheets/doeymp0010.shtml). *Office of Civilian Radioactive Waste Management*. 131. ["Oklo's Natural Fission Reactors"](http://www.ans.org/pi/np/oklo). *[[American Nuclear Society]]*. 132. (February 2016). ["Backgrounder: Tritium, Radiation Protection Limits, and Drinking Water Standards"](https://www.nrc.gov/docs/ML0620/ML062020079.pdf). *United States Nuclear Regulatory Commission*. 133. ["Radionuclides in Groundwater"](https://www.nrc.gov/reactors/operating/ops-experience/tritium/rn-groundwater.html). *nrc.gov*. ::callout[type=info title="Wikipedia Source"] This article was imported from [Wikipedia](https://en.wikipedia.org/wiki/Nuclear_reactor) and is available under the [Creative Commons Attribution-ShareAlike 4.0 License](https://creativecommons.org/licenses/by-sa/4.0/). Content has been adapted to SurfDoc format. 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