The Interstate Transmission System (ISTS) in India is undergoing significant expansion to facilitate the integration of renewable energy sources.

 The Interstate Transmission System (ISTS) in India is undergoing significant expansion to facilitate the integration of renewable energy sources. Currently, a large number of ISTS schemes are under implementation or planned, with a focus on strengthening the grid to evacuate power from renewable energy projects, particularly solar and wind. These schemes include both transmission line additions and increased substation capacity.

Key aspects of the current ISTS development:

Renewable Energy Integration:

A major driver for ISTS development is the need to evacuate power from the growing capacity of renewable energy projects.

Transmission Line Expansion:

Thousands of circuit kilometers (ckm) of transmission lines are under construction, with a significant portion being developed under the Tariff-Based Competitive Bidding (TBCB) mechanism.

Substation Capacity Augmentation:

Simultaneously, substantial increases in substation transformation capacity (MVA) are being planned and implemented to handle the power flow.

Green Energy Corridors:

The Green Energy Corridor (GEC) projects, both at the inter-state (ISTS) and intra-state (InSTS) levels, are crucial for strengthening the transmission network in renewable energy-rich states.

HVDC Transmission:

High Voltage Direct Current (HVDC) corridors are being planned for the evacuation of power from large renewable energy zones.

Transmission Charge Waivers:

To incentivize the development of energy storage, particularly Battery Energy Storage Systems (BESS) and Pumped Hydro Storage (PHS), the Ministry of Power has extended ISTS transmission charge waivers.

National Grid Integration:

ISTS aims to create a unified energy market by eliminating state-wise transmission restrictions and facilitating power transfer based on demand.

Specific Initiatives:

Green Energy Corridor Phase-II:

The Cabinet Committee on Economic Affairs has approved the Green Energy Corridor (GEC) Phase-II – Inter-State Transmission System (ISTS) for 13 GW Renewable Energy Project in Ladakh.

InSTS GEC:

The InSTS GEC scheme is under implementation in several states for evacuating renewable energy.

ISTS-TBCB:

A large number of ISTS projects are being awarded under the Tariff-Based Competitive Bidding (TBCB) mechanism, with significant transmission line and substation capacity additions.

Inter-Regional Transmission Capacity:

The planned and ongoing ISTS projects aim to increase the inter-regional transmission capacity to about 150,000 MW by 2030.

Challenges:

Land Acquisition and Right-of-Way:

Delays in land acquisition and Right-of-Way (RoW) issues continue to be a challenge in some projects.

Forest Clearances:

Obtaining forest clearances for transmission line construction can also cause delays.