Generation II reactor

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Generation II reactor vessels size comparison.

A generation II reactor is a design classification for a nuclear reactor, and refers to the class of commercial reactors built up to the end of the 1990s.[1] Prototypical generation II reactors include the PWR, CANDU, BWR, AGR, VVER[1] and RBMK.

These are contrasted to generation I reactors, which refer to the early prototype of power reactors, such as Shippingport, Magnox/UNGG, Fermi 1, and Dresden.[1] The nomenclature for reactor designs, describing four 'generations', was proposed by the US Department of Energy when it introduced the concept of generation IV reactors.

The designation generation II+ reactor is sometimes used for modernized generation II designs built post-2000, such as the Chinese CPR-1000, in competition with more expensive generation III reactor designs. Typically, the modernization includes improved safety systems and a 60-year design life.[citation needed]

Generation II reactor designs generally had an original design life of 30 or 40 years.[citation needed] This date was set as the period over which loans taken out for the plant would be paid off. However, many generation II reactor are being life-extended to 50 or 60 years, and a second life-extension to 80 years may also be economic in many cases.[2] By 2013 about 75% of still operating U.S. reactors had been granted life extension licenses to 60 years.[3]

Fukushima Daiichi's three destroyed reactors are Mark I Boiling water reactors (BWR) designed by General Electric. In 2016, unit 2 at the Watts Bar Nuclear Generating Station came online and is likely to be the last generation II reactor to become operational.

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  1. ^ a b c Jamasb, Tooraj; William J. Nuttall; Michael G. Pollitt (2006). Future electricity technologies and systems (illustrated ed.). Cambridge University Press. p. 203. ISBN 978-0-521-86049-9. 
  2. ^ "No reason why NPPs cannot live beyond 60". Nuclear Engineering International. 1 October 2010. Archived from the original on 13 June 2011. Retrieved 14 October 2010. 
  3. ^ "Renewal a bridge to replacement". World Nuclear News. 19 December 2013. Retrieved 21 December 2013. 

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