The United States tops the list, with nearly 100 operational nuclear reactors, providing a total net electricity capacity of 98,708 megawatts. Next on the list is France, with 58 reactors, and Japan is in third place, though, as of August 11, 2015 only one reactor out of 43 is online. Worldwide, there are currently 449 operational nuclear reactors, with a further 56 new plants under construction.

Now, nuclear reactors operate in 31 countries. Most are in Europe, Northern America, East Asia, and South Asia. Only France, Hungary, Slovakia and Ukraine use them specifically as a major source of electricity for the country.

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