A nuclear power phase-out is the discontinuation of usage of nuclear power for energy production. Often initiated because of concerns about nuclear power, phase-outs usually include shutting down nuclear power plants and looking towards fossil fuels and renewable energy. Three nuclear accidents have influenced the discontinuation of nuclear power: the 1979 Three Mile Island partial nuclear meltdown in the United States, the 1986 Chernobyl disaster in the USSR (now Ukraine), and the 2011 Fukushima nuclear disaster in Japan.
As of 2023[update], only two countries have permanently closed all of their formerly functioning nuclear plants: Italy by 1990, and Germany by 2023. Lithuania and Kazakhstan have shut down their only nuclear plants, but plan to build new ones to replace them, while Armenia shut down its only nuclear plant but subsequently restarted it. Austria never used its first nuclear plant that was completely built. Cuba, Libya, North Korea and Poland never completed the construction of their first nuclear plants due to financial, political and technical reasons. Spain and Switzerland plan nuclear phase-outs.[2][3][4][5]
Nuclear shut-downs after Fukushima have significantly set back emissions reductions goals in several countries. A 2019 study of the impacts of the German and Japan closures concludes that by continuing to operate their nuclear plants "these two countries could have prevented 28,000 air pollution-induced deaths and 2400 Mt CO2 emissions between 2011 and 2017. By sharply reducing nuclear instead of coal and gas after Fukushima, both countries lost the chance to prevent very large amounts of air pollution-induced deaths and CO2 emissions".[6]
Several countries formerly opposed to opening nuclear programs or planning phaseouts have reversed course in recent years due to climate concerns and energy independence including Belgium,[7] the Philippines,[8] Greece,[9] Sweden[10] and South Korea.[11]