Russia began first criticality stage of two nuclear power units last week, including the innovative Unit 1 of the Leningrad Nuclear Power Plant-2

On December 8, the first fuel assembly was successfully loaded into the nuclear reactor core of  Unit 1 of Leningrad Nuclear Power Plant-2. Thus, the first criticality stage began. This stage comprises the loading of nuclear fuel, the attainment of the controlled nuclear chain reaction, and taking the reactor unit to the minimum controlled power level. 

LNPP-2 will use power units equipped with the latest Generation III+ VVER-1200 reactors, which correspond (are aligned with) the post-Fukushima safety measures. Earlier this month Bangladesh began the construction of the country’s first nuclear power plant at Rooppur, which will have two VVER-1200 units. Moreover, Russia offered same reactors to India for the construction of nuclear power plant of Russian design at the second site after Kudankulam NPP. 

The first criticality is one of the key stages of putting a power unit into operation with the main task to confirm that the unit will operate reliably and safely at design parameters during its entire service life. 

“Within 30 days, the reactor facility will be brought to the minimum controlled power level. These operations involve a large range of inspections and tests at different stages during the increase to the power level, as well as testing and revision of various items of equipment to confirm the reliability and safety of the power unit for further operation," said Andrey Petrov, Director General of Rosenergoatom, a Russian nuclear power plants operations subsidiary of Rosatom State Atomic Energy Corporation.

“Unit 1 of the Leningrad Nuclear Power Plant-2 belongs to the latest Generation III+. This is the second innovative unit of its kind. In February 2017, Russia became the world’s first country to launch a nuclear power unit of Generation III+ at the Novovoronezh Nuclear Power Plant,” added Valery Limarenko, President of ASE Group of Companies, an engineering division of Rosatom State Atomic Energy Corporation. 

On December 6, the fuel loading also began at Unit 4 of the Rostov Nuclear Power Plant with VVER-1000 reactor. Thus, for the first time in its history Russia is launching two NPPs in just a week’s time.

VVER-1000 reactors are installed at nuclear power plants in Russia, China, Bulgaria and other countries, with India’s Kudankulam NPP being one of them.


Light-water reactors, using normal water under pressure have been developed and constructed in Russia and are known as VVER-type reactors. In such reactors, water serves both as a neutron moderator and as a reactor coolant.

The VVER-type reactors are considered to be some of the safest reactors worldwide and form the basis of the Russian nuclear industry development program and export expansion. The experience of successfully operating nuclear power plants with VVER-type reactors has already exceeded 1,400 accident-free reactor-years. 

The VVER-1200 units will be constructed on the basis of Generation III + technology. The innovative power generation units have improved technical and economic parameters that ensure absolute safety of operation and fully meet the post-Fukushima requirements of the International Atomic Energy Agency (IAEA). 

The VVER-1200 reactor has 20% higher power capacity (1,200 MW) compared to the VVER-1000 of the previous generation. Its core equipment also has an extended 60-year design life, compared to the 30 years of previous generation reactors.

The main feature of the VVER-1200 project is its unique combination of active and passive safety systems that provides maximum resistance against external and internal influences.

The passive safety systems are capable of functioning even in the event of a complete loss of power supply. They can provide full safety without the active systems and an operator.

Leningrad Nuclear Power Plant

The Leningrad NPP is the largest producer of electricity in Northwest Russia. It is located in Sosnovy Bor, 40 km from the city of St. Petersburg and produces around 50% of the electricity generated in the region.

Rostov Nuclear Power Plant

Rostov NPP is located 13.5 km from the city of Volgodonsk. It is the largest enterprise of the power sector in South Russia, which produces 46% electricity in the region. The commissioning of Unit 4 will bring the share of the plant in electricity production to 54%.
Russia launches two nuclear power units in a week
Russia launches two nuclear power units in a week