The pace of completions of ISTS-TBCB projects appears to have slowed down this fiscal year with only two such schemes getting fully commissioned in the first half (H1: April to September) of FY25.
According to a special study by T&D India based on official statistics, two interstate transmission system (ISTS) schemes were fully commissioned during H1FY25, contributing 592 ckm of transmission lines and 1,000 MVA of substation capacity to the ISTS network.
Both the projects were commissioned in the second quarter (Q2: July to September) with the first quarter (Q1: April to June) recording nil completions.
In September 2024, Gadag Transmission Ltd, a subsidiary of ReNew Transmission Ventures (part of ReNew Power Group), commissioned its ISTS project termed as “Transmission system for Gadag Solar Energy Zone (1,000 mw), Karnataka, Part A, Phase I.” This project based in Karnataka included the new 1,000-MVA Gadag pooling station and a 400kV double-circuit line of 187 ckm connecting this pooling station to the Narendra (New) substation of Power Grid Corporation of India Ltd. With an estimated cost of Rs.365 crore, this project was originally scheduled to commission by September 2023.
Earlier, in August 2024, PGCIL had commissioned its ISTS-TBCB scheme housed under “Powergrid Bhadla Transmission Ltd.” This project was stymied by GIB-related issues and its commissioning was delayed by over 16 months. This scheme, with an envisaged outlay of Rs.1,106 crore, involved the setting up of 405 ckm of 765kV lines connecting the two substations – Fatehgarh II and Bhadla II – in Rajasthan.
These two projects contributed 592 ckm of transmission lines and 1,000 MVA of transformation capacity to the ISTS grid.
Project delays
According to an analysis based on officially-available statistics, around 13 projects that were scheduled to commission by September 30, 2024, are still under construction. These projects, by current thinking, are now expected to commission between October 2024 and as late as May 2026. In many instances, delay in securing right-of-way is seen as a major contributory factor to overall project delay.
Sterlite Power: Mumbai Urja Marg
While the above discussion takes into account fully commissioned projects only, it needs to be mentioned that Sterlite Power commissioned three transmission lines aggregating 223 ckm and one substation of 1,000 MVA – all part of the ISTS-TBCB project housed under “Mumbai Urja Marg Ltd.” This project, earlier known as “Vapi-II North Lakhimpur Transmission Ltd” is massive scheme spanning several states across northeast and western India. According to information available with T&D India, apart from the four elements now commissioned, a few others have already been commissioned earlier. The project is learnt to be on the way to full commissioning, with only a few small elements like the 5-ckm LILO involving PGCIL’s Navi Mumbai substation in Maharashtra, pending completion.
The western region-based components of the Mumbai Urja Marg Ltd project have already started transmitting around 1,500 MW of green energy to Mumbai, a highly-placed official of Sterlite Power told T&D India.
Projects awarded in H1FY25
As discussed in a recent story, the first half (H1: April to September) of FY25 saw the formal award of as many as 14 ISTS-TBCB schemes with PGCIL emerging as the most successful with seven wins.
ISTS growth in H1FY25
It may be noted that in H1FY25, a total of 815 ckm of transmission lines and 12,515 MVA of transformation capacity was added to the ISTS network. While 592 ckm of transmission lines and 1,000 MVA of substation capacity was added by the two fully-commissioned ISTS-TBCB schemes as discussed in this story, the remaining came from ISTS projects on regulated tariff mechanism (RTM), and completion of elements of ISTS-TBCB schemes pending full commissioning, as seen in “Mumbai Urja Marg Ltd” discussed in this story.
ISTS-TBCB completions in FY24
According to statistics available with T&D India, a total of nine ISTS-TBCB schemes were fully commissioned in the whole of FY24, contributing 4,079 ckm of lines and 16,500 MVA of transformation capacity to the interstate grid. Developers credited with these commissioned projects included PGCIL (four projects), Adani Energy Solutions (three), Renew Transmission Ventures (two); and, G R Infraprojects and India Grid Trust (one each).
Featured photograph (source: IndiGrid) is for representation only
