Nuclear technology was first developed in the 1940s, and during the Second World War research initially focused on producing bombs. In the 1950s attention turned to the peaceful use of nuclear fission, controlling it for power generation. For more information, see page on History of Nuclear Energy.
Nuclear energy is defined as a source of power which is created from energy released by a nuclear reaction. Nuclear reactors serve three general purposes:
- Civilian Reactors are used to generate energy for electricity and sometimes also steam for district heating;
- Military Reactors create materials that can be used in nuclear weapons; and
- Research Reactors are used to develop weapons or energy production technology, for training purposes, for nuclear physics experimentation, and for producing radio-isotopes for medicine and research.
According to Word Nuclear Association, as of March 2020, the Nuclear Power in the World:
- The first commercial nuclear power stations started operation in the 1950s;
- Nuclear energy now provides about 10 percent of the world’s electricity from about 440 power reactors;
- Nuclear is the world’s second largest source of low-carbon power (29 percent of the total in 2017); and
- Over 50 countries utilize nuclear energy in about 220 research reactors. In addition to research, these reactors are used for the production of medical and industrial isotopes, as well as for training.
The uses of nuclear technology extend well beyond the provision of low-carbon energy. It helps control the spread of disease, assists doctors in their diagnosis and treatment of patients, and powers our most ambitious missions to explore space. These varied uses position nuclear technologies at the heart of the world’s efforts to achieve sustainable development.
Civil nuclear power can now boast more than 17,000 reactor years of experience, and nuclear power plants are operational in 30 countries worldwide. In fact, through regional transmission grids, many more countries depend in part on nuclear-generated power; Italy and Denmark, for example, get almost 10 percent of their electricity from imported nuclear power.
Number of Operable Reactors Worldwide 2020