Unit 2 of the Leningrad II nuclear power plant in Sosnovy Bor, in Western Russia, was connected to the national grid today for the first time. Following this trial operation, the unit will be shut down for an additional equipment inspection by a state commission, Rosatom said, before being put into commercial operation, which is scheduled for 2021. The new unit will replace Leningrad unit 2, which is an RBMK-1000 reactor.

Leningrad II-2 in Sosnovy Bor (Image: Rosatom)

Before its connection to the grid, the VVER-1200 reactor - also known as Leningrad NPP unit 6 - underwent the power ascension tests designed to assess the readiness of its main equipment and systems to produce both thermal and electric power, as well as a step-by-step increase in thermal capacity from 1% to 35%. Reaching 35% thermal capacity, the turbine generator was connected to the grid and started generating and transmitting electricity to the country’s unified power system.

"There are two important milestones in the power unit start-up process. One is initially bringing the reactor to a critical state at the minimum-controlled power level when it 'awakens'," Rosatom First Deputy Director General for Operations Management Alexander Lokshin said. "The second, which is even more important, is its first connection to the grid, when the power unit begins to perform its function and produce electricity. Today, the country received another 1200-megawatt unit and strengthened its credibility as a leading power in the field of nuclear energy," he added.

The new unit was connected to the unified power system and tested at a capacity of 240 MWe, Director General of Rosenergoatom Andrey Petrov said, adding that the next step is trial operation, when the reactor is tested at up to 100% power capacity.

"Each stage is accompanied by numerous equipment checks and dynamic operational tests aimed at stimulating shutdown at various power levels," he said.

The existing Leningrad plant site has four RBMK-1000 units, while Leningrad II will have four VVER-1200 units. Leningrad unit 1 was shut down for decommissioning on 21 December last year. Leningrad II unit 1 was connected to the grid on 9 March 2018.

Researched and written by World Nuclear News

Date: Saturday, 24 October 2020
Original article: world-nuclear-news.org/Articles/Leningrad-II-unit-2-starts-grid-connected-trial-op