Ministry of Power Sets Standard Timelines for ISTS Projects

The Ministry of Power along with the Central Electricity Authority (CEA), has established standardized implementation timelines for Inter-State Transmission System (ISTS) projects to enhance coordination, planning efficiency, and predictability in project execution.

On 15 April 2026, the National Committee on Transmission (NCT), in its 40th meeting, approved these timelines for various configurations of ISTS projects to ensure better predictability and coordinated system development.

Below are the timelines prescribed for different ISTS project components:

1. Substation Development

   • Greenfield 765kV / 400kV Substations (AIS/GIS/Hybrid): 36 months

   • Greenfield 220kV / 132kV Substations: 24 months

2. High Voltage Direct Current (HVDC) Systems

   • HVDC Systems (Line + Substation): 48—54 months

3. Transmission Lines

   • 765kV Double Circuit Line (<100 km): 30 months

   • 765kV Double Circuit Line (>100 km): 36 months

   • 400kV Double Circuit Line (<50 km): 24 months

   • 400kV Double Circuit Line (>50 km): 30 months

   • 220kV / 132kV Lines: 24 months

4. Substation Augmentation

   • Existing AIS Substations (400kV and above): 30 months

   • Existing AIS Substations (220/230kV and below): 24 months

   • Existing GIS/Hybrid Substations (132kV and above): 30 months

   The memorandum further notes that:

   • Projects in hilly or difficult terrain regions (NER, Sikkim, J&K, Ladakh, and Himachal Pradesh) may receive a 6—12 month extension based on terrain challenges.

   • For multi-component schemes, the overall timeline is based on the longest activity, with flexibility for compression in urgent cases.

Also Read: State Commissions cannot modify tariff adopted by Central Commission and adopt trade margin for ISTS power projects: APTEL

Also Read: Ministry of Power reduces maximum time limit for granting new connections and modifying existing connections

[ISTS Project Timeline Notification]