NHPC Achieves Major Milestone: 250 MW Unit Synchronized in India's Largest 2,000 MW Hydropower Project

India's largest hydroelectric initiative, the Subansiri Lower HE Project, reached a significant milestone as NHPC successfully synchronized Unit-2, a 250 MW component, with the National Grid. This achievement marks a pivotal moment for the 2,000 MW mega dam project located in Arunachal Pradesh.

According to NHPC's official statement, the commissioning process began with Units 1 and 2, which underwent mechanical testing on October 24 and November 6 respectively. The organization further indicated that synchronization of the remaining three units—Units 1, 3, and 4—will follow after completion of thorough testing protocols.

The initial phase of the project will generate 1,000 MW of power output. Once fully operational, the Subansiri Lower HE Project is projected to generate 7.421 billion units of renewable energy annually, significantly bolstering India's energy infrastructure and advancing the nation's carbon neutrality objectives.

The development journey of this project has not been without challenges. After receiving approval in January 2005 at Gerukamukh on the Arunachal Pradesh-Assam border, construction was suspended for eight years between 2011 and 2019 due to anti-dam protests. Work finally resumed in October 2019.

NHPC elaborated on the power allocation strategy: "As a national endeavour, power allocation follows central hydropower regulations. Assam will receive not only its standard allocation of 208 MW but also a preferential 300 MW allotment plus 25 MW of free electricity. Arunachal Pradesh will benefit from 12% free power in accordance with national hydropower policy. The remaining capacity will be distributed among other states, including those in northeastern India."

Upon complete commissioning, the 2,000 MW capacity installation will substantially enhance India's renewable energy portfolio while significantly improving electricity accessibility throughout the strategically important northeastern region. This remarkable achievement aligns perfectly with India's broader strategy to expand clean energy production and reduce dependency on fossil fuel generation.