Generation III reactor

A Generation III reactor is a development of Generation II nuclear reactor designs incorporating evolutionary improvements in design developed during the lifetime of the Generation II reactor designs. These include improved fuel technology, superior thermal efficiency, significantly enhanced safety systems (including passive nuclear safety), and standardized designs for reduced maintenance and capital costs. The first Generation III reactor to begin operation was Kashiwazaki 6 (an ABWR) in 1996.

Due to the prolonged period of stagnation in the construction of new reactors and the continued (but declining) popularity of Generation II/II+ designs in new construction, relatively few third generation reactors have been built. Generation IV designs are still in development as of 2017^[update], and are not expected to start entering commercial operation until 2020–2030.

Though the distinction is arbitrary, the improvements in reactor technology in third generation reactors are intended to result in a longer operational life (60 years of operation, extendable to 120+ years of operation prior to complete overhaul and reactor pressure vessel replacement) compared with currently used Generation II reactors (designed for 40 years of operation, extendable to 80+ years of operation prior to complete overhaul and pressure vessel replacement).

The core damage frequencies for these reactors are designed to be lower than for Generation II reactors – 60 core damage events for the EPR and 3 core damage events for the ESBWR per 100 million reactor-years are significantly lower than the 1,000 core damage events per 100 million reactor-years for BWR/4 Generation II reactors.

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