Breeder reactors research was quite huge (one of the first breeder was built in the US in 1951). Then this technology has been, for all practical purposes, aba

Breeder reactors research was quite huge (one of the first breeder was built in the US in 1951). Then this technology has been, for all practical purposes, abandoned by nearly all countries that were researching and developing it. See https://en.wikipedia.org/wiki/Breeder_reactor#Future_plants https://en.wikipedia.org/wiki/Breeder_reactor#Future_plants One of the most (if not the most) ambitious project was Superphénix, costed billions and failed flat. https://en.wikipedia.org/wiki/Superph%C3%A9nix https://en.wikipedia.org/wiki/Superph%C3%A9nix The sole officially actively pursued pertinent design, BREST-OD-300 ( https://en.wikipedia.org/wiki/BREST_(reactor) https://en.wikipedia.org/wiki/BREST_(reactor) ), was planned to be built in 2020 ( https://www.world-nuclear-news.org/NN_Fast_moves_for_nuclear_development_in_Siberia_0410121.html https://www.world-nuclear-news.org/NN_Fast_moves_for_nuclear... ) and real work didn't even began ( https://www.world-nuclear-news.org/Articles/Russia-awards-contract-to-build-BREST-reactor https://www.world-nuclear-news.org/Articles/Russia-awards-co... ). Moreover it will only (when built, if ever, but not before 2026) be a demonstrator (low power).