12 March 2018

Five Years Late: Grid Connection of First Unit of Leningrad‑II Nuclear Plant in Russia

Five Years Late: Grid Connection of First Unit of Leningrad-II Nuclear Plant in Russia

WNISR, Monday, 12 March 2018

Russia connected the VVER 1200 series reactor, Leningrad-II unit 1 to the grid, 9 March 2018, ten years after construction start in 2008 and five years later than the original scheduled startup in 2013. It is the second Rosatom VVER 1200 to enter service, following the Novovoronezh-6 grid connection on 5 August 2016. The Leningrad plant, is located at Sosnovy Bor, in northwest Russia, on the Gulf of Finland. The Leningrad Phase II project plans 4 VVER 1200 reactors, while Leningrad-I is an operating four-unit, Chernobyl-type RMBK-1000 plant.

There are two variants of the VVER 1200, of which the Leningrad-II units 1&2 are V491, designed by Atomenergoproekt St. Petersburg, while the two units at Novovoronezh are V392M, designed by Atomenergoproekt Moscow. Independent analysis commissioned by the Austrian government to assess the 1200 series V491 design, and planned for Fennovoima in Finland and which relies more on active safety features compared with the passive safety centered design of the V392M. The assessment concluded that the safety features of the VVER 1200 have significant uncertainties. The experts noted that while, “significant efforts have been undertaken by the designer to fulfill the safety objectives, but available information does not permit a definitive assessment.” Both designs raised questions over the reliable function of the core catcher, regarding description of accident scenarios, timing of core flooding to avoid steam explosion and guaranteeing inversion of metallic and oxydic layers in the catcher vessel. While a number of hazardous phenomena are claimed to be controlled by through design, there is evidence that they have not been eliminated as required by the safety objective, including steam explosion, hydrogen detonation, re-criticality and direct containment heating. Rosatom has offered the VVER-1200 Pressurized Water Reactor (PWR) design, also called AES-2006, with a capacity of 1200 MW in various countries, including Bangladesh, Egypt, Finland and Vietnam. Two units are under construction in Belarus. However, the design has not been licensed in any western country. The operation of Leningrad II unit 1 is the second reactor startup in the world in 2018, following on from the Rostov 4 reactor on 1 February, also in the Russian Federation. Four additional reactors remain under construction in Russia, including two more VVER 1200 and two small 32 MW “floating reactors”. All are currently scheduled to start up before the end of 2019.