Russia’s Federal Environmental, Industrial and Nuclear Supervision Service (Rostechnadzor) has issued a second additional service life extension licence for unit 4 of Novovoronezh NPP for 13 years. The licence enable the unit to operate for 60 years instead of 30 years as designed.
More than 40 modifications, including safety improvements, were carried out to prepare the VVER-440 reactor for additional service as part of a major overhaul and upgrade.
“We have developed and implemented new, modern safety systems,” said Andrey Dementiev, deputy director general and director for production and operation at nuclear utility Rosenergoatom (part of state nuclear corporation Rosatom). “For example, as well as the active cooling system, a passive system can be used. It consists of special tanks with boron solution which, if necessary, can be injected into the reactor core to cool it down. There was no such system in the initial design of the unit, which is now fully compliant with most modern requirements despite having been designed in the 1960s”.
Upgrading of Novovoronezh 4 began in 2017, and in January 2019, it was brought to its rated capacity. A two-year Rostekhnadzor licence for an additional extended life was obtained at the end of 2017, and in 2018 a new set of documents was sent to Rostekhnadzor. Based on these and the results of the operation of the new and upgraded systems, Rostekhnadzor issued a licence until the end of 2032.
Novovoronezh 4, a 385 MWe VVER V-179 pressurised water reactor unit, began commercial operation in March 1973.
There are four commercially operational reactor units at the Novovoronezh site: Novovoronezh 4, Novovoronezh 5 (a VVER-1000) and two newer VVER-1200 units, Novovoronezh- II 1 and Novovoronezh- II 2.