[glenneroo]

There are currently zero reactors worldwide which are using up-to-date designs i.e. Gen IV, as it is still being designed with the first reactor expected to be built by ~2030. All reactors worldwide are Gen II (designed in the 50s), Gen II+ (updated Gen II with a end-of-life extension to 60 years instead of Gen II's 40) or Gen III, which have relatively minor differences according to the World Nuclear Association[0]. The last Gen I reactor finally went offline in 2015.

> 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, and are not expected to start entering commercial operation until 2020–2030.[1]

[0]: http://www.world-nuclear.org/information-library/nuclear-fue...

[1]: https://en.wikipedia.org/wiki/Nuclear_reactor#Reactor_types