Commercial Operation of the first Unit of Country’s Largest Hydropower Project

The Union Minister of Power on 24 December 2025 inaugurated the commercial operation of Unit–2 (250 MW) of the 2000 MW Subansiri Lower Hydroelectric Project through virtual mode.

Key Facts

• Project Capacity: 2000 MW (8 units × 250 MW)
• Location: Subansiri River (Arunachal Pradesh–Assam)
• Developer: NHPC
• Type: Run-of-the-River scheme with small pondage
• Annual Generation: ~7,422 million units (MU) of renewable electricity

Current Status

• Unit–2 (250 MW) commissioned
• Three units to be commissioned shortly
• Remaining four units to be commissioned during 2026–27

Engineering & Infrastructure Highlights

• Largest hydropower project in India
• Largest dam in North-East India
  • 116 m high concrete gravity dam
• Water diversion through 8 Head Race Tunnels (HRTs)
• Enhances:
  • Grid resilience
  • Flood moderation
  • Water management in the Subansiri basin

Power Distribution & Benefits

• Supplies power to 16 beneficiary states
• Free power allocation to:
  • Arunachal Pradesh
  • Assam
• 1,000 MW allocated to the North-East region
• Boosts regional energy security and clean power availability

Source: PIB