Higher availability and longer operating life – typically 60 years.
A simpler and more rugged design, making them easier to operate and less vulnerable to operational upsets.A more standardised design for each type to expedite licensing, reduce capital cost and reduce construction time.So-called third-generation reactors have: Fourth-generation reactors are at the R&D or concept stage. Reactor suppliers in North America, Japan, Europe, Russia, China and elsewhere have a dozen new nuclear reactor designs at advanced stages of planning or under construction, while others are at a research and development stage. These and other nuclear power units now operating have been found to be safe and reliable, but they are being superseded by better designs. Over 85% of the world's nuclear electricity is generated by reactors derived from designs originally developed for naval use. Generation IV designs are still on the drawing board and will not be operational before the 2020s. The first ones are in operation in Japan and others are under construction in several countries. So-called Generation III (and III+) are the advanced reactors discussed in this paper, though the distinction from Generation II is arbitrary. Generation II reactors are typified by the present US and French fleets and most in operation elsewhere. Generation I reactors were developed in 1950-60s, and the last one shut down in the UK in 2015. Several generations of reactors are commonly distinguished. The nuclear power industry has been developing and improving reactor technology for more than five decades and is starting to build the next generation of nuclear power reactors to fill new orders. * For smaller advanced reactors see the companion page on Small Nuclear Power Reactors. These are described in a separate information paper.* Many new designs are small – up to 300 MWe.They are more fuel efficient and are inherently safer. Newer advanced reactors now being built have simpler designs which are intended to reduce capital cost.The first so-called Generation III advanced reactors have been operating in Japan since 1996.Improved designs of nuclear power reactors are constantly being developed internationally.