Bulgaria's Kozloduy NPP has signed a contract with a consortium including Russia's Rusatom Service and Bulgarian engineering services provider Risk Engineering to extend the operating life of the plant's unit 6 by up to 60 years.
The agreement was reached during a meeting of the Bulgarian-Russian Intergovernmental Commission for Economic, Scientific and Technical Cooperation.
Energy Minister Temenouzhka Petkova said the complex technological process is involves specific timeframes and will be carried out by "a consortium uniting two very serious companies". The service life of Kozloduy 6 is due to expire in 30 months, said Rusatom Service director general Evgeny Salkov. He noted that Risk Engineering is a reliable partner. The deadline for completion of its audit expires by the end of this year but part of the documentation will be ready earlier. Once the analyses are submitted to the Nuclear Regulatory Agency which will make a decision within nine months. The maximum term for which the regulator may extend the licence for operation is 10 years. Rusatom Service said it will prepare justification for operation of up to 30 years. The unit began commercial operation in December 1993
Bulgaria has two units in commercial operation, Kozloduy 5 and 6, both 1000MWe Russian-built VVER V-320 pressurised water reactors. The plan to extend the operating lives of these units was launched in April 2012 when Kozloduy NPP signed a contract with a consortium of Russian nuclear utility Rosenergoatom and EDF. Early in 2013 a further contract was signed with Rusatom Services to upgrade the turbine generator of unit 6, taking it to 1100MWe by installing a new stator, with work completed in November 2015.
In October 2014, Bulgaria awarded a contract for the lifetime extension of unit 5 to a French-Russian consortium consisting of France's EDF, Rosenergoatom and Rusatom Service. A €24.7m ($26.75m) agreement with Russian state nuclear corporation Rosatom was signed in October 2015 was for upgrading the turbine generator of unit 5 by May 2018. The government is committed to their life extension and uprate to 104% of original capacity. The operational licence for Kozloduy 5 expires in 2017 and the licence for Kozloduy 6 in 2019. Some 30% of Bulgaria's electricity is generated at Kozloduy.
Rosatom said the work includes an assessment of the "technical condition and justification of the residual service life" of the reactor equipment, the thermal and mechanical equipment of the first and second circuits, the diesel generator power units, and other equipment, buildings and structures of Kozloduy 6. The work is expected to take 30 months.