Of the 31 countries in which nuclear power plants operate, only France, Slovakia, Ukraine, Belgium, and Hungary use them as the source for a majority of the country’s electricity supply. Other countries have significant amounts of nuclear power generation capacity.[10] By far the largest nuclear electricity producers are the United States with 805 647 GWh of nuclear electricity in 2017, followed by France with 381 846 GWh.[10] As of December 2017 448 reactors with a net capacity of 391 721 MWe are operational and 59 reactors with net capacity of 60 460 MWe are under construction, of those 18 reactors with 19 016 MWe in China.[11]

(data from Wikipedia)

Nuclear power by country in 2017[10][9][1]
Country Reactors Capacity
Net-total (MWe)
Generated
electricity (GWh)
Share of total
electricity use
Notes
operational U/C
Argentina Argentina 3 1 1633 5716.27 4.5%
Armenia Armenia 1 0 375 2411.39 32.5%
Bangladesh Bangladesh 0 1 N/A N/A N/A
Belarus Belarus 0 2 N/A N/A N/A
Belgium Belgium 7 0 5918 40186.70 49.9%
Brazil Brazil 2 1 1884 14854.33 2.7%
Bulgaria Bulgaria 2 0 1926 14872.26 34.3%
Canada Canada 19 0 13554 95131.20 14.6%
China China 39 19 34514 232796.74 3.9%
Czech Republic Czech Republic 6 0 3930 26784.68 33.1%
Finland Finland 4 1 2769 21573.97 33.2%
France France 58 1 63130 381846.02 71.6%
Germany Germany 8 0 10799 72162.80 11.6% Phase-out by 2022
Hungary Hungary 4 0 1889 15218.92 50.0%
India India 22 6 6255 20004.34 3.2%
Iran Iran 1 0 915 6366.21 2.2%
Japan Japan 42 2 39752 29285.05 3.6% Most reactors currently stopped
South Korea Korea, Republic of 25 2 23070 141278.32 27.1%
Mexico Mexico 2 0 1552 10571.92 6.0%
Netherlands Netherlands 1 0 482 3263.18 2.9%
Pakistan Pakistan 5 2 1318 8108.93 6.2%
Romania Romania 2 0 1300 10580.15 17.6%
Russia Russia 35 7 26142 190115.15 17.8%
Slovakia Slovakia 4 2 1814 14015.82 54.0%
Slovenia Slovenia 1 0 688 5967.83 39.1%
South Africa South Africa 2 0 1860 15087.29 6.7%
Spain Spain 7 0 7121 55627.75 21.2%
Sweden Sweden 9 0 9102 63062.89 39.6%
Switzerland Switzerland 5 0 3333 19590.70 33.4% Phase-out planned
Taiwan Taiwan 6 2 5052 21560.47 9.3%
Turkey Turkey 0 2 N/A N/A N/A
Ukraine Ukraine 15 2 13107 80405.85 55.1%
United Arab Emirates United Arab Emirates 0 4 N/A N/A N/A
United Kingdom United Kingdom 15 0 8918 63886.83 19.3%
United States United States 99 2 99952 805647.33 20.0%
World total 451 59 394,054 MWe 2,488 TWh