Kudankulam Unit-3 enters reactor-stage commissioning with key system milestone
India’s largest nuclear power station has progressed in its expansion, with Nuclear Power Corporation of India Limited (NPCIL) initiating the “Spillage to Open Reactor” process for Unit-3 of the Kudankulam Nuclear Power Project (KKNPP) on April 25, 2026.
The activity involves flushing and conditioning of safety systems and main coolant pipelines using light water. It establishes cleanliness levels in the primary circuit required for subsequent commissioning stages and enables the start of individual functional testing of primary system equipment for the 1000 MW unit.
The milestone was inaugurated by B. C. Pathak, Chairman and Managing Director of NPCIL, in the presence of Mikhail Novikov, Director for Projects in India at ASE (Atomstroyexport), the engineering arm of Russia’s Rosatom State Corporation, reflecting ongoing Indo-Russian collaboration on the project.
Located in Tirunelveli district, Tamil Nadu, the Kudankulam site remains central to India’s nuclear power programme. The first two units are operational and have generated over 121 Billion Units of electricity, avoiding nearly 104 million tonnes of CO₂ equivalent emissions.
Construction of Units 3, 4, 5, and 6 is underway. Once completed, the site is expected to reach a total installed capacity of 6,000 MW, strengthening India’s baseload capacity and low-carbon energy mix.
NPCIL stated that it continues to follow established standards for safety, quality, and environmental management across project execution.