There are currently 449 nuclear reactors operating in 31 countries, with total installed generating capacity of more than 390,000 megawatts, based on data from the International Atomic Energy Agency. Nuclear power plants differ in various ways, including reactor types, vessel containments, cooling methods and dispatch purposes.

The Bruce Nuclear Generating Station, located on Lake Huron in Ontario, Canada, is currently the world’s largest operating nuclear power plant. Bruce has eight reactors configured into two separate facilities operating four reactor units each, for a combined installed capacity of 6,274 MW.