In 2025, India's Interstate Transmission System (ISTS) is seeing significant expansion to accommodate renewable energy growth, with a focus on both large-scale transmission projects and green energy corridors.

 In 2025, India's Interstate Transmission System (ISTS) is seeing significant expansion to accommodate renewable energy growth, with a focus on both large-scale transmission projects and green energy corridors. A key development is the extension of ISTS charge waivers for storage projects, encouraging further investment in Pumped Storage Projects (PSP) and Battery Energy Storage Systems (BESS).

Key Developments:

Expansion of ISTS Capacity:

India has installed 48 GW of ISTS capacity for renewable energy evacuation and has 159 GW under construction, with a total planned capacity of 340 GW to evacuate 230 GW of renewable energy.

Green Energy Corridors:

Intra-state transmission systems (InSTS) are being strengthened through Green Energy Corridor (GEC) schemes to facilitate renewable energy integration at the state level.

ISTS Charge Waivers:

The Ministry of Power extended the waiver of ISTS charges for storage projects, including PSPs and BESS, until June 2028.

Private Sector Participation:

Private companies are increasingly involved in ISTS projects through Tariff-Based Competitive Bidding (TBCB), with many projects expected to be commissioned by the end of FY27.

Land Acquisition:

The government increased compensation for land used in transmission line construction to address Right of Way (RoW) issues.

Renewable Energy Integration:

ISTS facilitates the integration of renewable energy sources like solar and wind into the national grid, contributing to India's decarbonization goals.

Increased Power Availability:

These efforts have contributed to increased power availability, with average power availability reaching 22.5 hours in rural areas and 23.5 hours in urban areas.

Specific ISTS Projects:

Eastern Region: Schemes include the "Eastern Region Generation Scheme – I (ERGS-I)" in Odisha, where H.G. Infra Engineering Ltd. was declared the L1 bidder, according to T&D India.

North Eastern Region: Schemes include "NER Expansion Transmission Ltd".

Western Region: Schemes include "Raghanesda RE Transmission Ltd".

Northern Region: Schemes include "Transmission scheme for integration of Bijapur REZ in Karnataka".

PGCIL: Power Grid Corporation of India Limited (PGCIL) is commissioning several ISTS-TBCB schemes.

Future Outlook:

The ISTS network is expected to continue expanding to meet the growing demand for electricity and the increasing share of renewable energy in India's energy mix.

The government's focus on strengthening both ISTS and InSTS will be crucial for achieving India's ambitious renewable energy targets.

The extension of ISTS charge waivers for storage projects will further incentivize investment in these crucial technologies.