New Delhi: NHPC Limited has commenced commercial operations of the fourth unit of the Subansiri Lower Hydroelectric Project, marking a key milestone in the country’s renewable energy expansion.
The company confirmed that Unit 4 achieved Commercial Operation Date (CoD) from 00:00 hours on May 8, 2026. With this, 1,000 MW of capacity from the project is now operational.
Project Location and Scale
The project is located near North Lakhimpur, along the border of Arunachal Pradesh and Assam.
Once fully commissioned, the hydropower plant will have a total installed capacity of 2,000 MW, making it the largest hydropower project in India. The remaining units are expected to become operational by the end of 2026.
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Key Features and Power Generation
The Subansiri project is designed as a run-of-the-river scheme with minimal storage. Its major highlights include:
- Eight head race tunnels (HRTs)
- Annual generation capacity of 7,422 million units (MU)
- Significant contribution to clean and renewable energy
The project is expected to play a vital role in strengthening India’s power grid, especially in the northeastern region.
Delays and Challenges
The project has witnessed a long and challenging journey since its inception:
- Initially scheduled for completion in December 2012
- Construction began in 2005 after forest clearance in 2004
- Work stalled between 2011 and 2019 due to protests over environmental and safety concerns
- Legal hurdles addressed through the National Green Tribunal
Construction resumed in October 2019 after resolving all regulatory issues.
Cost Escalation
The project cost has increased significantly over time—from an initial estimate of ₹6,285 crore in 2002 to approximately ₹27,000 crore, largely due to delays and extended timelines.
Boost to Renewable Energy Goals
With multiple units now operational, the Subansiri project is expected to:
- Enhance India’s renewable energy capacity
- Support clean power generation
- Reduce dependence on fossil fuels
- Improve energy security in the region
About NHPC Limited
NHPC Limited is a Navratna public sector enterprise and India’s leading hydropower company. Headquartered in Faridabad, it focuses on the development and operation of hydroelectric and renewable energy projects across the country, playing a key role in India’s clean energy transition.
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