India's Kudankulam Unit-5 Reactor Vessel Installed with Russian Support

New Delhi: The Nuclear Power Corporation of India Limited (NPCIL) has completed the installation of the reactor pressure vessel (RPV) at Unit-5 of the Kudankulam Nuclear Power Project (KKNPP) in Tamil Nadu, with support from Russia's nuclear energy corporation Rosatom.

The RPV is the steel component that houses the nuclear reactor and fuel. Its installation marks a key milestone in the construction of a nuclear power plant.

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The installation took place on June 15 with the participation of the engineering division of Rosatom, the project's general designer and contractor. The reactor vessel was manufactured at the Atommash plant of Rosatom's Machine-Building Division in Volgodonsk.

The RPV, which weighs around 320 tonnes, houses the reactor core where nuclear fission takes place.

The operation was carried out using the open-top method, in which equipment is installed into the reactor building using a heavy-duty crane before the dome is erected. This method was previously practised by the joint team from India and Russia during the second phase of construction at the KKNPP.

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"The secret to the success of the Kudankulam NPP project is the long-standing and fruitful cooperation between India and Russia," said Mikhail Novikov, director of projects in India at Russia's Atomstroyexport. "Indian specialists are constructing and commissioning four power units based on the Russian design, while two more power units have already been generating electricity for over 10 years..."

The NPCIL, in a statement, said the milestone reflected close cooperation between the corporation and Russia's Atomstroyexport (ASE), highlighting the importance of international collaboration in India's nuclear energy programme.

The NPCIL said it reflected India's vision for energy security, environmental responsibility and sustainable development under the Nuclear Energy Mission for Viksit Bharat.

The Kudankulam Nuclear Power Plant project is being implemented within the framework of the Intergovernmental Agreement on Cooperation in the Construction of a Nuclear Power Plant in India, concluded on November 20, 1988, and the amendment to it dated June 21, 1998. Its units 1 and 2 were connected to the Indian national grid in 2013 and 2016. respectively. As of April 2026, they have generated over 127 b kWh of electricity. Power units 3, 4, 5 and 6 are the second and third stages of the Kudankulam NPP, each equipped with a WWER-1000 reactor.

Once all six reactors become operational, the plant will have a total installed capacity of 6,000 MWe, making it one of the country's largest nuclear power facilities.