Nuclear power, the use of nuclear reactions to produce electricity, can be obtained from nuclear fission, nuclear decay, and nuclear fusion reactions. Presently, the vast majority of electricity from nuclear power is produced by nuclear fission of uranium and plutonium in nuclear power plants. Nuclear decay processes are used in niche applications such as radioisotope thermoelectric generators in some space probes such as the Voyager 2 probe. Like these two processes, generating electricity from fusion power remains the current focus of international research.

In the United States, these research efforts led to the creation of the first man-made nuclear reactor, the Chicago Pile-1, which achieved criticality on December 2nd, 1942. The reactor’s development was part of the Manhattan Project, the allied effort to create nuclearbombs during World War II. It led to the building of larger, single-purpose production reactors for the production of weapons-grade plutonium for use in the first nuclear weapons. The United States tested the first nuclear weapon in July 1945, the Trinity Test, with the atomic bombings of Hiroshima and Nagasaki taking place one month after the test.

Nuclear energy originates from the splitting of uranium atoms – a process called fission. This generates heat to produce steam, which is used by a turbine generator to createelectricity. Because nuclear power plants do not burn any fuel, they do not produce greenhouse gas emissions. By providing power 24 hours a day, nuclear energy is an important part of the energy mix necessary to meet electricity demand. And, with no carbon emissions, it will remain an important clean energy resource for the future. For more than 40 years, Duke Energy has operated nuclear plants – setting industry benchmarks for safety and efficiency in the process. We employ redundant and diverse safety systems to protect the public, our employees and the environment.

The first organization to develop practical nuclear power was the U.S. Navy, with the S1W reactor for the purpose of propelling submarines and aircraft carriers. The first nuclear-powered submarine, USS Nautilus, was put to sea in January 1954. The S1W reactor was a Pressurized Water Reactor. This design was chosen because it was simpler, more compact, and easier to operate compared to alternative designs; thus, it was more suitable to be used in submarines. This decision would result in the PWR being the reactor of choice also for power generation, thus having a lasting impact on the civilian electricity market in the years to come. On June 27, 1954, the Obninsk Nuclear Power Plant in the USSR became the world’s first nuclear power plant to generate electricity for a power grid, producing around 5 megawatts of electric power for Soviet citizens. The world’s first commercial nuclear power station, Calder Hall at Windscale, England, was connected to the British national power grid on 27 August 1956. In common with a number of other generation I reactors, the plant had the dual purpose of producing electricity and plutonium-239, The total global installed nuclear capacity initially rose relatively quickly, rising from less than 1 gigawatt (GW) in 1960 to 100 GW in the late 1970s. During the 1970s and 1980s rising economic costs (related to extended construction times largely due to regulatory changes and pressure-group litigation) and falling fossil fuel prices made nuclear power plants then under construction less attractive. In the 1980s in the U.S. and 1990s in Europe, the flat electric grid growth and electricity liberalization also made the addition of large new baseload energy generators economically unattractive.