Rishikesh, 01.10.2024: THDC India Limited, a leading PSU, is making significant progress on the 444 MW Vishnugad-Pipalkoti Hydro Electric Project (VPHEP) in Chamoli, Uttarakhand. Sh. R. K. Vishnoi, CMD, THDCIL, informed that a major milestone was reached in September 2024 when the Double Shield Tunnel Boring Machine (TBM) "NANDAKI" completed 509 meters of the Head Race Tunnel (HRT), which involves installing 2,016 concrete-lined segments—a notable feat given the challenging Himalayan geology.
THDC is committed to establishing organizational excellence through state-of-the-art technology and in this context, he further mentioned that in the same month, THDCIL set a record by boring 29 meters of HRT in a single day, highlighting their advanced technological capabilities in this rugged terrain. The TBM is equipped with a 19-inch disc cutter head and large bucket openings, enabling efficient excavation of hard rock, supported by a powerful 4,200 kW electric drive that delivers torque of over 22,000 kNm. As it progresses, the TBM installs reinforced concrete lining rings consisting of six segments and fills the gap with pea gravel and grouting, ensuring structural integrity.
The project's alignment navigates complex geological formations, including dolomitic limestone, slate, and various critical zones like thrust, shear, and fault zones, which present substantial engineering challenges. Despite these obstacles, THDCIL has completed 3,252 meters of mining with the TBM.
The 444 MW VPHEP, funded by World Bank is designed as a run-of-river hydroelectric project, featuring a 65-meter high dam that utilizes a gross head of 237 meters on the Alaknanda River. The HRT has an 8.8-meter diameter and extends 13.4 kilometres to an underground powerhouse, with a planned discharge of 228 Cumec. After the generation of power, the flow of water will seamlessly flow back into the Alaknanda River through a 9.1-meter diameter tunnel extending 3.1 km.
This project aims to enhance energy capacity in the Northern region, addressing peaking power shortages and generating an estimated 1,657 million units of electricity, with 12% free power allocated to the Uttarakhand state government.
Beyond Energy Generation, VPHEP is committed to integrated Regional Development, enhancing Employment opportunities, Communication, Education, Health, Tourism, and Environmental Conservation in the regional area. This initiative exemplifies THDCIL's dedication to leveraging technology for sustainable growth and regional advancement.
