Operable nuclear reactors worldwide 2021, by country

As of October 2021 there are 441 nuclear reactors in operation in some 30 countries around the world. In the United Kingdom, 13 nuclear power reactors were in operation as of this time. Operable nuclear reactors are those connected to the grid.

Nuclear reactors under construction

The largest plant under construction as of 2021 are situated in Finland and UK with a gross electricity generation capacity of 1,720 megawatts. Meanwhile, the country with highest total electric capacity of nuclear reactors under construction worldwide is China, where almost 14 gigawatts of nuclear reactors were being built.

History of nuclear energy generation

In 1954, history was made when nuclear fission technology was approved for commercial purposes and the first nuclear power plant started operation in the Russian city of Obninsk. For the first time, it was possible to meet the demand of an increasingly energy-thirsty world – at a reasonable price, too. The new energy proved to be an extremely reliable and stable form of electricity. Since nuclear power plants are only shut down for refuelling about every two years, they provide an around-the-clock “baseload” supply of power to the people.

In nuclear fission, uranium atoms are split apart into lighter elements. Uranium is a radioactive metal that is extracted from mines, mainly in Kazakhstan, Canada and Australia. After the uranium splitting process, the used fuel elements are still radioactive and have to be stored in nuclear waste repositories or spent fuel pools. These sites are often underground and require thick metal or concrete walls to shield the public from radiation.