PGCIL approves Rs 856 crore HTLS upgrade for two Tamil Nadu 400 kV lines
The Committee of Directors on Investment on Projects of Power Grid Corporation of India Limited (PGCIL) has approved an investment of Rs 856.94 crore for the reconductoring of the Tirunelveli–Udumalpet and Pugalur–Madurai 400 kV double-circuit transmission lines in Tamil Nadu. The project will replace the existing conductors with High Temperature Low Sag (HTLS) conductors to increase the power transfer capacity of the two transmission corridors while utilising the existing tower infrastructure.
The investment approval was granted at the committee’s meeting held on August 5, 2026. The project will be booked under Additional Capital Expenditure and is scheduled for commissioning within 24 months from the date of project allocation, with completion targeted by February 11, 2028.
Project
The approved works cover the reconductoring of the Tirunelveli–Udumalpet and Pugalur–Madurai 400 kV double-circuit transmission lines using HTLS conductors.
HTLS conductors can operate at higher temperatures than conventional conductors, enabling higher current-carrying capacity while maintaining acceptable sag levels. This allows the transmission capacity of existing lines to be enhanced without requiring major modifications to transmission towers, reducing the need for new transmission infrastructure.
Network
The two transmission corridors form part of the Southern Region transmission network, where power flows have increased with the rapid addition of renewable energy capacity and rising inter-regional power transfers.
The latest approval follows another transmission strengthening investment by PGCIL in Tamil Nadu. In June 2026, the company approved an investment of Rs 772.65 crore to upgrade the Udumalpet–Madurai 400 kV single-circuit transmission line into a Udumalpet–Madurai 400 kV (quad) double-circuit transmission line. The project was taken up to increase power transfer capacity and improve grid reliability in the state amid rising renewable energy integration and higher transmission loading.
With the latest investment, PGCIL continues to expand transmission capacity in Tamil Nadu through upgrades of existing assets to accommodate growing electricity demand and renewable energy flows.
The featured photograph is for representation only.
