Union Minister Shri Manohar Lal inaugurates commercial operation of Unit-2 of Subansiri Lower Hydroelectric Project

Key facts

• The Subansiri Lower Hydroelectric Project is India’s largest hydropower project with a total capacity of 2000 MW, comprising eight units of 250 MW each.
• The project is designed as a Run-of-the-River scheme with small pondage, utilizing eight Head Race Tunnels (HRTs) to generate 7,422 million units (MU) of renewable electricity annually.
• The infrastructure features a 116-metre-high concrete gravity dam, which is the largest dam in North-East India.
• The project incorporates technical milestones including India’s heaviest hydro generator rotors, largest stators, and the first-ever use of Rotec’s Tower Belt for dam concreting in the country.
• It provides flood moderation with a 442 million cubic metre flood cushion and a gross reservoir storage of 1,365 million cubic metres at Full Reservoir Level (FRL).
• NHPC Limited (NHPC) has implemented riverbank protection and erosion control measures extending up to 60 km downstream with an investment of approximately ₹522 crore.
• The project will provide free power allocations to Arunachal Pradesh and Assam, with the North-East region receiving a total of 1,000 MW.