Power Grid Corporation of India Ltd (PGCIL) has planned to upgrade the Udumalpet-Madurai transmission line in Tamil Nadu.
The 400kV Udumalpet-Madurai line is currently a single-circuit one and the plan will involve converting the same to a 400kV double-circuit (quad) line.
Commissioned in April 1993, the line is currently operating very close to its surge impedance loading (SIL) limit during the peak winter season. The line is very old – having completed over 23 years of operation – and is currently witnessing high thermal loading.
During a meeting of National Committee on Transmission (NCT) in February this year where the project was discussed, it was highlighted that the thermal loading of this line is about 850 MVA and under conditions, maximum loading of about 750 MW has been observed.
The need for upgrading the Udumalpet-Madurai line has also arisen due to high renewable energy (mainly wind energy) injection.
The PGCIL board recently accorded investment approval to the project, which is estimated to cost Rs.772.65 crore and with an implementation timeframe of 30 months.
The project, assigned to PGCIL under the regulated tariff mechanism (RTM) framework, is scheduled for commissioning by August 11, 2028.
Project scope
The 400kV Udumalpet-Madurai single-circuit line, running about 127 km (also ckm, as it has a single circuit), will be converted into a 400kV double-circuit (quad) line. One 400kV line bay each at Udumalpet and Madurai will also be part of the project. Besides, existing bay equipment at the Udumalpet and Madurai ends will also be upgraded.
PGCIL has confirmed that space is available for existing bays at the existing Udumalpet and Madurai substations.
More projects in TN
Apart from the Udumalpet-Madurai line project discussed in this story, NCT, in its meeting of February 2026, also approved reconductoring of two important lines in Tamil Nadu. See tndindia.com story dated February 11, 2026 for more details.
Featured photograph is for representation only