Nuclear Power


The first nuclear power generation reactor is a small experimental reactor (EBR-1), designed and operated by the Argon National Laboratory and located in Idaho, USA. The reactor started work in December 1951.

In the Soviet Union, an existing reactor for the production of plutonium with moderator graphite was modified to produce heat and power and in June 1954 in Obninsk began working the world’s first generator of electricity with nuclear power. The AM-1 reactor was water-cooled and graphite for moderator, with a design power of 30 MWt or 5 MWe.

In the United States, Westinghouse designed the first fully civilian pressure-water reactor (PWR) of 250 MWe, Yankee Rowe, which began operating in 1960 and operated until 1992. Meanwhile, the boiling water reactor (BWR) 250 MWe was developed by the National Laboratory in Argon and designed by General Electric, and was commissioned earlier in the same 1960 year. By the end of the 60’s in the US more than 1000 MWe PWR and BWR nuclear units were ordered. The development of the Canadian reactor CANDU goes on a completely different path, using natural uranium fuel and heavy water as a moderator and coolant. The first unit started in 1962. This design of CANDU continues to be Improved today. In France, the first-reactor MAGNOX began operating in 1956, and their exploitation for civilian purposes began in 1959. In 1964, the first two Soviet nuclear power plants have been put into operation. A reactor with graphite of 100 MW with boiling water begins in the Beloyarsk (Urals). A small pressurized water reactor (210 MW), known as VVER (water-cooled energy reactor), was built in the Novovoronej (Volga). The first large High-Power Channel Reactors (HPCR)  (1000 MW-channel reactor) started in Somnovi Bor near Leningrad in 1973, and in the Arctic, northwest, began working VVER reactor with a nominal capacity of 440 MW. There was developed 1000 MWe version also, which became a standard design for Russian reactors of this generation. In Kazakhstan, the world’s first civilian prototype of a fast neutron reactor (BN-350) was launched in 1972 with a design capacity of 135 MWe (net) producing electricity and heat for desalination of Caspian Sea water.

Now, the civil nuclear energy has produced more than 17 000 reactor years, and nuclear power plants operate in 30 countries around the world. Indeed, through regional transmission networks, many more countries depend partly on nuclear energy; Italy and Denmark, for example, receive almost 10% of their electricity from imported nuclear energy.

Nuclear Energy Worldwide

11% of global electricity is generated by 450 nuclear reactors. Almost 60 reactors are under construction, which amounts to 16% of the existing capacity. In 2017 nuclear power plants have delivered 2487 TWh electricity compared to 2477 TWh in 2016.1 This is the fifth consecutive year in which the world atomic generation has risen, with output of 142 TWh higher compared to 2012.

In 2017, 13 countries have produced at least a quarter of their electricity from nuclear energy. France receives about three quarters of its electricity from nuclear energy; Hungary, Slovakia and Ukraine receive more than half of nuclear energy, while Belgium, Sweden, Slovenia, Bulgaria, Switzerland, Finland and the Czech Republic receive one-third or more. South Korea receives more than 30% of its electricity from nuclear power, while in the US, UK, Spain, Romania and Russia about one-fifth of the electricity is from nuclear energy. Japan was accustomed to relying on nuclear power for more than a quarter of its electricity and is expected to return somewhere close to that level.

Nuclear Power in Bulgaria

35% of Bulgaria’s electricity is produced by nuclear energy. Bulgaria developed nuclear energy from the 60’s of 20 century and according to the adopted energy strategy until 2020 will continue to rely on this ecologically clean source of energy. The construction and commissioning of new power generation facilities on the basis of light water reactor technology from the latest generations III or III+ at Kozloduy site is approved in principle by the Government of Bulgaria in April 2012. This is expected to have a significant positive effect on employment and economic growth, especially in the northwestern region of Bulgaria, and to contribute to the conservation and development of scientific and technical potential in the nuclear energy sector, to ensure reliable and affordable electricity supply in Bulgaria and the Balkan region, and to achieve long-term greenhouse gas emission reduction. For management and realization of the project in May 2012 Kozloduy NPP PLC has established a subsidiary company – Kozloduy NPP – New Build EAD, which currently conducts feasibility studies in order to prepare the government decision on the merits, necessary to start the construction.

The first in Bulgaria WWER-440 was introduced in the operation in Kozloduy NPP in 1974, followed by the second WWER-440 in 1975. In 1980 and 1982, two more WWER-440 were put into operation, followed by two WWER-1000 in 1987 and 1991. Thus the electricity from nuclear energy in Bulgaria increased from 2 800 000 MWh in 1974. To 28 000 000 MWh in 1991. Due to the commitments made by Bulgaria on the occasion of the country’s accession to the European Union, Kozloduy NPP ceased the operation of the first WWER-440 four power plants before the expiration of their projected resource, which was 30 fuel campaigns. Currently, the annual electricity production in Bulgaria of Nuclear energy is about 16 000 000 MWh.