New Delhi: Power Grid Corporation of India Limited (POWERGRID) has approved an investment of ₹856.94 crore to upgrade two major 400 kV transmission lines in Tamil Nadu as part of its ongoing efforts to strengthen the country’s power transmission network and enhance grid capacity.
The investment was approved by the Committee of Directors on Investment on Projects during its meeting held on August 5, 2026, according to a regulatory filing submitted to the stock exchanges.
Two Major Transmission Lines to Be Upgraded
The approved project involves the reconductoring of the following 400 kV double-circuit transmission lines using High Temperature Low Sag (HTLS) conductors:
- Tirunelveli–Udumalpet 400 kV Double-Circuit Transmission Line
- Pugalur–Madurai 400 kV Double-Circuit Transmission Line
The project will be executed under POWERGRID’s Additional Capital Expenditure programme and is aimed at increasing the transmission capacity and improving the operational efficiency of the existing power infrastructure.
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₹856.94 Crore Investment with February 2028 Completion Target
POWERGRID has estimated the total project cost at ₹856.94 crore.
Project Highlights
- Project Cost: ₹856.94 crore
- Location: Tamil Nadu
- Transmission Lines: Tirunelveli–Udumalpet and Pugalur–Madurai
- Technology: High Temperature Low Sag (HTLS) conductors
- Implementation: Additional Capital Expenditure programme
- Target Completion Date: February 11, 2028
- Execution Timeline: Within 24 months from the date of project allocation
HTLS Conductors to Boost Transmission Capacity
The project will replace the existing conductors with High Temperature Low Sag (HTLS) conductors, which are designed to carry higher power loads while maintaining lower sag compared to conventional conductors.
Benefits of HTLS Technology
- Enhances power transmission capacity
- Improves operational efficiency of existing lines
- Supports rising electricity demand
- Minimises the need for new transmission corridors
- Optimises the use of existing transmission infrastructure
The upgrade will help strengthen existing transmission corridors without requiring new line alignments, making the network more efficient and reliable.
Part of POWERGRID’s Network Strengthening Strategy
According to the company, the project is part of its broader strategy to modernise and strengthen India’s interstate transmission network.
By upgrading existing infrastructure, POWERGRID aims to improve grid reliability, ensure efficient power evacuation and support the country’s growing electricity demand while making optimum use of available assets.
About POWERGRID
Power Grid Corporation of India Limited (POWERGRID) is a Maharatna Central Public Sector Enterprise under the Ministry of Power. It is India’s largest electric power transmission utility, responsible for planning, developing, operating and maintaining the country’s interstate transmission network. POWERGRID plays a key role in ensuring reliable electricity transmission, integrating renewable energy into the national grid and supporting India’s expanding power infrastructure.
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