On September 4, 1974, the first reactor of the "Kozloduy" NPP was put into operation.
The “Kozloduy” nuclear power plant is the first nuclear power plant in Bulgaria and in Southeastern Europe.
The beginning of Bulgarian nuclear energy was set on July 15, 1966 with the signing of a cooperation agreement between Bulgaria and the then Soviet Union for the construction of a nuclear power plant. After a detailed technical and economic analysis, the construction site was selected on the Danube River, near the town of Kozloduy.
The “Kozloduy" NPP EAD is located 200 km north of the Bulgarian capital Sofia and 5 km east of the city of Kozloduy, on the banks of the Danube River.
The production facilities and auxiliary facilities of the plant are located on an area of about 1000 decares. The infrastructure of the "Kozloduy" NPP also includes its own shore pumping station and technical water supply channels, which bring the total area of the nuclear power plant to 4,471 decares.
The projects for the plant were prepared jointly by “Toploelektroproekt” - Moscow, and “Energoproekt” - Sofia. The main equipment was supplied by the Soviet Union, and individual facilities - from the then German Democratic Republic, Czechoslovakia and Hungary. The first sod for the construction of the “Kozloduy” NPP was laid in was made on October 14, 1969. In April 1970, large-scale construction activities began for the construction of the facility, which is still unique for our country, in which over one hundred thousand builders and installers participated.
Several entirely Bulgarian projects were implemented at the plant site, which were implemented for the first time in world practice in the construction of nuclear power plants. Some of these technical solutions are significant engineering achievements, to which specialists from other countries also show great interest.
On April 6, 1970, the construction of the main building of the Kozloduy NPP began, with a length of 240 m, a width of 105 m and a height of 40 m. It houses the reactor hall, the engine room, the ventilation center and the electrical devices of the 440-megawatt units. In June 1972, the first reactor arrived from the Soviet Union, and on November 20 of the same year it was lowered into its shaft.
The commissioning of the first nuclear power unit of the Kozloduy NPP in 1974 marked an important national achievement in the modern history of the country - the beginning of nuclear power not only in Bulgaria, but also in Southeastern Europe.
The construction and commissioning of the nuclear capacities of the Bulgarian nuclear power plant was carried out in three stages:
Stage I: 1970 - 1975 Construction and commissioning of units 1 and 2 with water-water reactors VVER-440, model B-230, with two independent channels of safety systems.
Commissioning of unit 1: 1974
Commissioning of unit 2: 1975
II stage: 1973 – 1982 Construction and commissioning of units 3 and 4 with water-cooled reactors VVER-440, an improved model B-230 with triple redundancy of safety systems.
Commissioning of unit 3: 1980
Commissioning of unit 4: 1982
Stage III: 1980 – 1991 Construction and commissioning of units 5 and 6 with VVER-1000 reactors, model B-320 with a hermetic protective shell, triple redundancy of safety systems.
Commissioning of unit 5: 1987
Commissioning of unit 6: 1991
In fulfillment of the commitments undertaken by Bulgaria in connection with the country's accession to the European Union, at the end of 2002 the operation of units 1 and 2 was terminated, and at the end of 2006 – on units 3 and 4.
By Decision of the Council of Ministers dated 20.12.2008, units 1 and 2 were declared facilities for radioactive waste (RW) management, and together with the necessary movable property were provided to the State Enterprise “RW” (SE RAW). The decision determined that “Kozloduy NPP” EAD should continue to operate these units in accordance with the obtained licenses for operation in the “E” state (without production of electricity and/or heat with storage of spent nuclear fuel in the reactor pool) until the relevant licenses were obtained from SE RAW.
On 18.10. In 2010, the NRA issued licenses to the State Agency for the Operation of Units 1 and 2 as facilities for the management of radioactive waste subject to decommissioning, and terminated the licenses of the Kozloduy NPP for the operation of the first two units in the operational mode - state "E".
Units 3 and 4 were declared as radioactive waste management facilities subject to decommissioning by a Decision of the Council of Ministers dated 19.12.2012. By the same decision, the two units with the necessary movable and immovable property were provided for management by the State Enterprise “RAO”. Until the necessary licenses are received from the State Enterprise RAW, “Kozloduy NPP” EAD continues to operate Units 3 and 4 in accordance with the current licenses for operation in the “E” mode.
On 25.02.2013, the NRA issued licenses to the State Enterprise RAW for the operation of Units 3 and 4 as radioactive waste management facilities subject to decommissioning. In connection with the issuance of the new licenses to the State Enterprise RAW, the licenses of “Kozloduy NPP” were terminated. EAD for the operation of units 3 and 4 in the operating mode – state “E”.
A new stage in the development of the nuclear power plant begins with the successful implementation of the strategic national energy project for the extension of the operating period of units five and six. The implementation of the project substantiates the possibility of long-term operation of the nuclear power plants – for the fifth unit until 2047, and for the sixth - until 2051. In 2017, the Nuclear Regulatory Agency (NRA) renewed the operating license of the fifth unit for 10 years. The license of the sixth unit for the next 10-year period was renewed in 2019. This is the maximum term according to national legislation. After its expiration, the nuclear power plant is to apply for the extension of the licenses of the units.