Nuclear Power Industry

The nuclear power industry generates electricity from nuclear reactions, overwhelmingly through the fission of uranium and plutonium in nuclear power plants. The first nuclear power plant was built in the 1950s, and global installed capacity grew to 100 gigawatts by the late 1970s and 300 gigawatts by 1990; the 1979 Three Mile Island accident in the United States and the 1986 Chernobyl disaster in the Soviet Union led to increased regulation and public opposition. Nuclear power plants supplied 2,602 terawatt hours of electricity in 2023, about 9 percent of global electricity generation and the second largest low carbon source after hydroelectricity. As of November 2025 there were 416 civilian fission reactors worldwide with a combined capacity of 376 gigawatts, plus 63 under construction and 87 planned; the United States has the largest fleet, generating almost 800 terawatt hours a year at an average capacity factor of 92 percent, and most new reactors under construction are generation III designs in Asia.