A new ISTS-TBCB scheme envisaging a new pooling station at Kadapa in Andhra Pradesh has been approved for implementation.
In its most recent meeting, National Committee on Transmission (NCT) approved an interstate transmission system (ISTS) scheme officially termed as “Transmission system for integration of Kadapa-II REZ (Phase-I)” with an estimated outlay of Rs.3,673 crore and gestation period of 36 months.
The scheme, straddling Andhra Pradesh and Tamil Nadu, will be implemented under the tariff-based competitive bidding (TBCB) mechanism with PFC Consulting Ltd (PFCCL) acting as the bid process coordinator.
Objective
The Kadapa-II REZ scheme aims to honour connectivity applications of 6,322MW received at the Kadapa-II PS. Applicants include Adani Renewable Energy Fifty-One Ltd for its upcoming pumped storage project (PSP) at Gandikota in YSR Kadapa district (commonly known as Kadapa district), in Andhra Pradesh. This PSP will have total capacity of 1,800 MW and connectivity of 600 MW has been sought by October 2028. (See related story). Connectivity application for 2,250 MW has also been received from Adani Hydro Energy Eleven Ltd, in June 2026.
At the NCT meeting, it was concurred that pumped storage projects will provide inertia support to the grid, thereby contributing to grid stability. PSPs will also provide a storage facility for RE generation, thereby facilitating optimal utilization of transmission infrastructure. [As RE power is used to pump up water into PSPs for electricity generation at a later stage, RE power, in the context of PSPs, is construed as an electricity “storage” facility.]
It was also decided at the NCT meeting that no battery energy storage system (BESS) project will be planned in cases where hybrid applications for solar and PSPs are received.
Project elements
The proposed ISTS-TBCB scheme primarily envisages a new pooling station (PS) at Kadapa in Andhra Pradesh. To be known as Kadapa-II PS, it will have transformation capacity of 3×1500 MVA at 765/400kV level, and 7×500 MVA at 400/220kV level.
This PS will be connected to the existing 765/400kV Thiruvalam GIS substation of Power Grid Corporation of India Ltd (PGCIL), located in Tamil Nadu’s Vellore district, through a 765kV double-circuit line running 226 km (not ckm).
Survey agency
It is reliably learnt that bid process coordinator PFCCL is in the process of appointing a technical consultant for conducting the LiDAR-based survey for the Kadapa-II project. The final selection will be made from among five technically qualified and empaneled entities – GIS Data Solutions, Pratik Surveyors (India) Pvt Ltd, MNEC Consultants Pvt Ltd, Knifedge Technologies Pvt Ltd and VITS Total Power Solution Pvt Ltd.
Featured photograph (source: pinggaoindia.com) shows the 765/400kV Thiruvalam GIS substation of PGCIL. This will be connected to the upcoming Kadapa-II PS through a 765kV double-circuit line, as envisaged in the ISTS-TBCB scheme discussed in this story.