Kozloduy Nuclear Power Plant

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Active reactors ( gross ):

Decommissioned Reactors ( gross ):

The Kozloduy nuclear power plant (also: Kozloduy Kozloduy or; Bulgarian Козлодуй ) is the only in-service nuclear power plant in Bulgaria. It is located 200 km north of Sofia, and five kilometers east of Kozloduy on the Danube. The construction of the nuclear power plant started on 6 April 1970.

History

A total of six pressurized water reactors were built with a total capacity of 3,760 MW at the Kozloduy site. Four units of the power plant are from the old Soviet type WWER-440/230 and were decommissioned in agreement with the European Union by the end of 2006. Units 1 and 2 have already been shut down in late 2002. Units 3 and 4 was followed on 31 December 2006, immediately prior to the EU accession of Bulgaria. The design and construction of units 5 and 6 is the newer Soviet type WWER-1000/320. Units 5 and 6 have a combined installed capacity of 1906 MW. These two blocks were modernized in 2007 and converted to Western security management system ( Teleperm XS).

Energy policy significance

All six blocks together were able to cover 44% of Bulgaria's electricity demand, allowing the country to export up to 20 % of its electricity production. After the closure of Units 3 and 4, this is no longer possible to this extent. For many countries in Southeast Europe, the shutdown and the associated increase in the price of electricity prices means that they can no longer maintain the power supply.

The Bulgarian government decided in April 2005, as compensation for the closure of the four blocks of the construction of the Belene nuclear power plant to resume, which rested since 1990. In February, 2013, with the decision to terminate the Belene project, the Bulgarian Parliament extended the remaining term of the two units at Kozloduy and decided to build another there.

While the gas dispute between Russia and Ukraine and thus resulting for Bulgaria natural gas shortage was pulled by President Georgi Parvanov considering to take the third reactor at Kozloduy block again. According to the Treaty of Accession of Bulgaria have in crisis situations, the right to do so. So the third reactor block can be put back into operation within one month, the fourth need some more time.

Incidents

In full load operation was founded in 2003 suddenly a leak at a weld of the primary circuit of the third reactor. The emergency cooling system came into operation. The now disused Units 1 to 4 were here - in contrast to the more powerful blocks 5 and 6 as well as all western pressurized water reactors - shut off individual segments of the primary circuit with valves. A shut-off was performed, whereby the loss of water after a relatively short period of time could be stopped.

During shutdown of the 5th block on 1 March 2006 remained after the failure of a main coolant pump 22 of the 60 controls in the upper position hang. This was due to an altered design of the control rods through the company Gidropress. It would thus have and can get through the loss of coolant to a meltdown. To shut down the reactor had boric acid are pumped into the reactor. The operator had originally classified the incident on the International Nuclear Event Scale evaluation with stage 0, but the safety authorities placed it at level 2. The incident became known only two months later. Four months later, the plant manager was fired. Gidropress was later accused that the new control rod design has not been tested. The company argued that similar control rods have been used in reactors in Russia.

Fuel rods

In August 2008, allegations of nuclear physicist Georgi Kotev who is responsible in the power plant for checking the quality of the fuel rods, announced that lower quality would be used with unknown properties in the power plant fuel rods. In October 2004, the fuel rods of the type TWSM have been replaced by fuel type TWSA. These new fuel rods were not consistent with those described in the documents. The deviations from the documented fuel properties was confirmed by the Bulgarian authorities and also by Prime Minister Sergei Stanishev. A security problem would thus not arise, which is denied by Western experts.

Because of a leak in the cooling circuit in early April 2013 were shut down a reactor of the nuclear power plant. At the site, the " safe storage " of nuclear waste for over 300 years has been approved by the EU. The repository, which will be built on land adjacent to the Kozloduy Nuclear Power Plant, is completed as planned by 2015.

Data of the reactor units

The Kozloduy nuclear power plant has a total of six blocks: