Nine ISTS-TBCB schemes fully commissioned in FY25, slowdown in transmission growth

Nine interstate transmission system (ISTS) schemes awarded through tariff-based competitive bidding (TBCB) were fully commissioned during FY25. Together, these projects represent around Rs 8.8 billion in annual transmission charges and involved a combined capital outlay of Rs 88 billion.

Of the nine schemes, Power Grid Corporation of India Ltd (PGCIL) developed five. Resonia (formerly Sterlite Power) commissioned two, while ReNew Transmission Ventures and Adani Energy Solutions Ltd (AESL) executed one each.

The total infrastructure delivered includes around 3,165 circuit kilometers (ckm) of transmission lines and 7,820 MVA of substation capacity. While the schemes were completed in FY25, some elements may have been commissioned earlier.

Among PGCIL’s five projects, three were for renewable energy evacuation from Rajasthan. These schemes faced time overruns exceeding two years, mainly due to delays over Great Indian Bustard habitat concerns.

The most complex scheme commissioned in FY25 was “Mumbai Urja Marg Ltd” by Resonia. It spanned northeastern states like Assam and Arunachal Pradesh and western states like Maharashtra and Gujarat. The project enables over 2,000 MW of green power flow to Mumbai and Navi Mumbai.

AESL completed its project under Khavda II-A Transmission Ltd in Gujarat in March 2025. It included a 765 kV double-circuit line of 355 ckm from Khavda Pooling Station-2 to Lakadia. It was commissioned on time and will support evacuation of 4.5 GW of renewable power.

Summary of schemes commissioned in FY25:

• PGCIL Projects
  
  
  • Powergrid Bhadla Transmission Ltd (RE evacuation, Rajasthan)
    
    
  • Powergrid Sikar Transmission Ltd (RE evacuation, Rajasthan)
    
    
  • Powergrid Aligarh Sikar Transmission Ltd (RE evacuation, Rajasthan)
    
    
  • Powergrid Dharamjaigarh Transmission Ltd (WRES XXVIII and XIX)
    
    
  • Powergrid Raipur Pool Dhamtari Transmission Ltd (WRES XXVII)
    
    
• ReNew Transmission Ventures
  
  
  • Gadag Transmission Ltd (RE evacuation, Karnataka)
    
    
• Resonia
  
  
  • Mumbai Urja Marg Ltd (WRSS XIX and NERSS IX)
    
    
  • Nangalbibra-Bongaigaon Transmission Ltd (220/132 kV substation, Meghalaya)
    
    
• AESL
  
  
  • Khavda II-A Transmission Ltd (RE evacuation, Gujarat)
    
    

Transmission sector slowdown in FY25

Despite these commissions, FY25 saw the lowest transmission line addition since FY15. Only 8,830 ckm of new lines were added, far below the planned 15,253 ckm. The previous low was in FY20, at 11,664 ckm.

Of the FY25 addition, 1,950 ckm – or 22 per cent – came in March 2025 alone.

In terms of ownership:

• The private sector added 1,483 ckm, nearly meeting its target of 1,586 ckm.
  
  
• The central sector, led by PGCIL, added only 2,586 ckm out of a planned 5,413 ckm.
  
  
• PGCIL alone added 2,534 ckm, falling well short of its 5,281 ckm target.
  
  

Voltage-wise, all categories underperformed. The largest shortfall was in the 765 kV category, where only 2,158 ckm was added against a plan of 4,703 ckm.

ISTS-specific addition was also weak, with just 3,253 ckm added—another record low since FY15. Intrastate additions stood at 5,577 ckm.

As of March 31, 2025, India’s total transmission line length (220 kV and above) was 494,374 ckm, a growth of only 1.8 per cent over the previous year. The interregional transfer capacity remained unchanged at 1,18,740 MW.

The Ministry of Power revised compensation rates in June 2024 to address RoW (right of way) issues, which are widely cited as the main hurdle in timely transmission development.