Back Kernreaktor Afrikaans مفاعل نووي Arabic Reactor nuclear AST Nüvə reaktoru Azerbaijani Ядзерны рэактар Byelorussian Ядзерны рэактар BE-X-OLD Ядрен реактор Bulgarian পারমাণবিক চুল্লী Bengali/Bangla Nuklearni reaktor BS Reactor nuclear Catalan

Nuclear reactor

This article is about nuclear fission reactors. For nuclear fusion reactors, see Fusion power.
"Nuclear pile" redirects here. For nuclear stockpiles, see List of states with nuclear weapons.
From top, left to right
  1. Chicago Pile-1, the first nuclear reactor
  2. Shippingport Atomic Power Station, the first peacetime reactor
  3. HTR-10, a prototype to the first Generation IV reactor, HTR-PM
  4. The Convair NB-36H, the first aircraft to test an onboard reactor
  5. Operation Sea Orbit, the first nuclear-powered circumnavigation
  6. The Chernobyl sarcophagus, built to contain the effects of the 1986 disaster

A nuclear reactor is a device used to initiate and control a fission nuclear chain reaction. They are used for commercial electricity, marine propulsion, weapons production and research. Fissile nuclei (primarily uranium-235 or plutonium-239) absorb single neutrons and split, releasing energy and multiple neutrons, which can induce further fission. Reactors stabilize this, regulating neutron absorbers and moderators in the core. Fuel efficiency is exceptionally high; low-enriched uranium is 120,000 times more energy dense than coal.[1][2]

Heat from nuclear fission is passed to a working fluid coolant. In commercial reactors, this drives turbines and electrical generator shafts. Some reactors are used for district heating, and isotope production for medical and industrial use.

Following the 1938 discovery of fission, many countries initiated military nuclear research programs. Early subcritical experiments probed neutronics. In 1942, the first artificial[note 1] critical nuclear reactor, Chicago Pile-1, was built by the Metallurgical Laboratory.[4] From 1944, for weapons production, the first large-scale reactors were operated at the Hanford Site. The pressurized water reactor design, used in ~70% of commercial reactors, was developed for US Navy submarine propulsion, beginning with S1W in 1953.[5] In 1954, nuclear electricity production began with the Soviet Obninsk plant.[6]

Spent fuel can be reprocessed, reducing nuclear waste and recovering reactor-usable fuel.[7] This also poses a proliferation risk via production of plutonium and tritium for nuclear weapons.

Reactor accidents have been caused by combinations of design and operator failure. The 1979 Three Mile Island accident, at INES Level 5, and the 1986 Chernobyl disaster and 2011 Fukushima disaster, both at Level 7, all had major effects on the nuclear industry and anti-nuclear movement.

As of 2025, there are 417 commercial reactors, 226 research reactors, and over 200 marine propulsion reactors in operation globally.[8][9][10][11] Commercial reactors provide 9% of the global electricity supply,[12] compared to 30% from renewables,[13] together comprising low-carbon electricity. Almost 90% of this comes from pressurized and boiling water reactors.[5] Other designs include gas-cooled, fast-spectrum, breeder, heavy-water, molten-salt, and small modular; each optimizes safety, efficiency, cost, fuel type, enrichment, and burnup.

  1. ^ "Nuclear Fuel Cycle Overview". World Nuclear Association. 20 May 2024. Retrieved 4 November 2024.
  2. ^ Science and Mathematics Education Research Group, University of British Columbia. "Physics Nuclear Physics: Nuclear Reactors" (PDF). Retrieved 4 November 2024.
  3. ^ Davis, E. D.; Gould, C. R.; Sharapov, E. I. (2014). "Oklo reactors and implications for nuclear science". International Journal of Modern Physics E. 23 (4): 1430007–236. arXiv:1404.4948. Bibcode:2014IJMPE..2330007D. doi:10.1142/S0218301314300070. ISSN 0218-3013. S2CID 118394767.
  4. ^ Cite error: The named reference :0 was invoked but never defined (see the help page).
  5. ^ a b Region, CountryBy TypeBy (29 August 2024). "In Operation & Suspended Operation". PRIS. Retrieved 30 August 2024.
  6. ^ Nuclear Engineering International: Obninsk - number one, by Lev Kotchetkov Archived 2 November 2013 at the Wayback Machine, who was there at the time. Source for most of the information in this article.
  7. ^ "Spent Fuel Reprocessing Options" (PDF). IAEA. Retrieved 30 August 2024.
  8. ^ "PRIS – Home". pris.iaea.org. Archived from the original on 11 February 2012. Retrieved 10 April 2019.
  9. ^ "RRDB Search". nucleus.iaea.org. Archived from the original on 18 September 2010. Retrieved 6 January 2019.
  10. ^ Oldekop, W. (1982), "Electricity and Heat from Thermal Nuclear Reactors", Primary Energy, Berlin, Heidelberg: Springer Berlin Heidelberg, pp. 66–91, doi:10.1007/978-3-642-68444-9_5, ISBN 978-3-540-11307-2, archived from the original on 5 June 2018, retrieved 2 February 2021
  11. ^ "Nuclear-Powered Ships". World Nuclear Association. 15 February 2023. Retrieved 31 December 2024.
  12. ^ "Nuclear Power in the World Today". World Nuclear Association. 6 January 2025. Retrieved 12 January 2025.
  13. ^ Ambrose, Jillian (7 May 2024). "Renewable energy passes 30% of world's electricity supply". the Guardian. Retrieved 12 January 2025.


Cite error: There are <ref group=note> tags on this page, but the references will not show without a {{reflist|group=note}} template (see the help page).

From Wikipedia, the free encyclopedia · View on Wikipedia

Developed by Nelliwinne