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, and VVER.[1]
These are contrasted to generation I reactors, which refer to the early prototype of power reactors, such as Shippingport, Magnox, 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 modernised generation II designs built post-2000, such as the Chinese CPR-1000, in competition with more expensive generation III reactor designs. Typically the modernisation includes improved safety systems and a 60 year design life.
Generation II reactor designs generally had an original design life of 30 or 40 years. 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]