The month of October 2024 proved very eventful for the ISTS-TBCB landscape with as many as three schemes getting fully commissioned.
According to latest statistics released by Central Electricity Authority (CEA), three interstate transmission system (ISTS) schemes awarded under the tariff-based competitive bidding (TBCB) route were fully commissioned during October 2024.
These included two by Sterlite Power and one by Power Grid Corporation of India Ltd (PGCIL). With this, the total number of ISTS-TBCB schemes fully commissioned in the first seven months (April to October) of FY25, stands at five. In a special report dated October 15, 2024, T&D India had indicated that two ISTS-TBCB schemes were fully commissioned in the first half (April to September) of FY25.
The most significant scheme commissioned in October 2024 was the ISTS-TBCB scheme of Sterlite Power housed under Mumbai Urja Marg Ltd (MUML) and officially known as “Western Region Strengthening Scheme – XIX and North Eastern Region Strengthening Scheme – IX”. It may be noted that the project SPV was earlier known as “Vapi-II North Lakhimpur Transmission Ltd.”
This composite project was spread over the western region (Gujarat and Maharashtra) as well as the northeastern region (Assam and Arunachal Pradesh). Among other features, this project is very instrumental in bringing green energy via Gujarat to the Mumbai city.
While elements of MUML had become operational since October 2022, the full commissioning of the project was achieved when the last element – a LILO of the 220kV double-circuit Apta-Kalwa/Taloja line at PGCIL’s Navi Mumbai substation – was commissioned in October 2024 after a delay of over two years. Land-related issues at PGCIL’s Navi Mumbai substation had significantly delayed the commissioning of this 5-km LILO, it is learnt. Most elements of this scheme in the western region, including the Vapi-II substation in Gujarat, were commissioned in September 2024.
Sterlite Power also fully commissioned its ISTS-TBCB scheme “Establishment of new 220/132kV substation at Nangalbibra” housed under project SPV Nangalbibra-Bongaigaon Transmission Ltd. This project involved setting up of the 220/132kV Nangalbibra substation in Meghalaya and associated lines in Assam and Meghalaya.
The third ISTS-TBCB completion in October 2024 was that by PGCIL when it fully commissioned a scheme incorporated under Powergrid Aligarh Sikar Transmission Ltd..Located in Rajasthan, this project mainly involved building of the 765kV double-circuit Sikar-II – Aligarh straddling Rajasthan and Uttar Pradesh, and measuring over 500 ckm. This project officially termed as “Transmission system for evacuation of power from solar energy zones in Rajasthan (8.1 GW) under Phase-II, Part D,” experienced a time overrun of over 18 months.
Cumulative FY25 status
The five ISTS-TBCB schemes commissioned in the first seven months (April to October) of FY25 involved three by the private sector (one by Renew Power and two by Sterlite Power) and two by PGCIL. The aggregate transmission infrastructure developed by these five schemes is estimated at 1,746 ckm of lines and 2,320 MVA of transformation capacity.
According to estimates made by T&D India, based on official statistics, ISTS-TBCB schemes commissioned in FY24 contributed 4,080 ckm of lines and 18,500 MVA of substation capacity to the interstate transmission system network.
Featured photograph (source: Sterlite Power) shows an element of the ISTS-TBCB scheme of Sterlite Power housed under “Lakadia Vadodara Transmission Project Ltd,” which was fully commissioned in January 2023.
