India’s accelerating renewable energy expansion is beginning to outpace the country’s transmission infrastructure, with nearly 300 gigawatt-hours (GWh) of clean electricity lost in the January-March quarter of 2026 due to transmission bottlenecks, according to a new analysis by energy think tank Ember.
The report estimated total renewable energy curtailment during the quarter at around 470 GWh, of which roughly 300 GWh was directly linked to inadequate transmission connectivity at key pooling stations. Northern India accounted for 178 GWh of curtailed power, followed by western India with 122 GWh. Southern India, by contrast, reported no transmission-related curtailment, suggesting relatively better alignment between renewable generation and evacuation infrastructure.
The scale of the problem became especially visible on March 30 this year, when India reportedly lost 34 GWh of renewable electricity in a single day. Ember said the amount was equivalent to the daily power consumption of nearly five million urban middle-class households. The findings arrive at a time when India is rapidly scaling up renewable capacity to meet its long-term climate and energy security goals. Yet, industry experts say the pace of transmission planning and execution has failed to keep up with the speed of renewable project commissioning.
Structural Mismatch
Calling the issue a structural challenge rather than a temporary disruption, Anujesh Dwivedi, Partner at Deloitte India, said the adequacy of the Inter-State Transmission System (ISTS) remains one of the biggest bottlenecks for renewable power evacuation.
Dwivedi pointed to data from Grid India showing that around 18,000 MW of renewable generation capacity across RE complexes currently lacks permanent grid connectivity through General Network Access (GNA), forcing developers to rely on Temporary General Network Access (T-GNA). “During hours between 11 am and 3 pm, against a requirement of 18,000 MW, only 6,470 MW of T-GNA margin was available. That means barely one-third of the required evacuation capacity was accessible during peak solar generation hours,” he said.
He added that delays in transmission execution are compounding the problem. According to CTUIL’s report on critical ISTS transmission lines under construction, projects are witnessing an average delay of 15 months between scheduled and anticipated commissioning dates. The imbalance between generation growth and evacuation readiness has widened sharply over the past two years. India added around 16 GW of renewable capacity annually between FY22 and FY24. That figure rose to 29 GW in FY25 and surged further to 51 GW in FY26.
Transmission expansion, however, has moved at a slower pace. Dwivedi noted that India achieved only around 80 per cent of its transmission line targets in FY2025-26, with 12,139 circuit kilometres added against a target of 15,382 ckm. To bridge the widening gap, CTUIL’s rolling transmission plan for 2030-31 has proposed adding 25,146 ckm of transmission lines in FY27 alone, almost double the average annual additions recorded over the past five years.
Grid Under Pressure
Virpal Yadav, Chief Operation Officer at Sunkind India, said the current curtailment reflects the pressure placed on a grid originally designed around thermal generation. “The renewable energy loss witnessed in Q1 2026 was primarily driven by interstate transmission congestion in renewable-rich states such as Rajasthan and Gujarat, where excess solar and wind power could not be evacuated efficiently to high-demand regions,” Yadav said.
He added that many Green Energy Corridor projects are still under development or awaiting full operational commissioning, while renewable generation projects are often completed faster than associated substations and transmission corridors. “More often than not, renewable projects were commissioned faster than the pace at which the associated substations, pooling stations and transmission corridors could be completed,” he said.
Yadav described many of the present constraints as transitional, but said they also reveal the long-term need for a more flexible and storage-enabled grid architecture. According to him, reducing future curtailment will require simultaneous investments in interstate transmission networks, large-scale storage systems and advanced grid management tools. “Battery Energy Storage Systems and pumped hydro storage will play a key role in storing surplus renewable energy and balancing demand during peak consumption periods,” he said, adding that AI-driven forecasting, real-time electricity markets and flexible dispatch systems will become increasingly important as renewable penetration rises.
Curtailment Hits Returns
Piyush Goyal, Co-Founder and CEO of Volks Energie, said the scale of renewable power loss shows that India’s transmission deficit is no longer a temporary operational issue. “The 300 GWh tells you one thing clearly. This is a structural mismatch, not a temporary glitch. We’re adding solar faster than we’re building the wires to carry it,” Goyal said.
He explained that many renewable projects currently operate under Temporary General Network Access because dedicated transmission systems are not yet ready. These projects are scheduled only after long-term GNA holders are served, leaving renewable generators exposed during periods of congestion. “In December 2025, on some days, roughly 4 GW of T-GNA solar capacity faced complete curtailment between 11 am and 2 pm, the exact window when solar is most productive,” he said.
Goyal warned that the impact is beginning to alter investment calculations for developers. According to him, transmission delays of six to twelve months can reduce project internal rates of return by 100 to 200 basis points, especially because T-GNA projects typically receive no compensation for curtailed generation. He argued that storage deployment may offer the fastest near-term relief. India currently has less than 2 GWh of operational battery energy storage capacity against nearly 43.7 GW of ISTS solar capacity deployed across major pooling stations. “That ratio is extraordinary, and it’s the single biggest reason midday solar gets curtailed instead of stored for evening peak,” he said.
Ember’s analysis warned that nearly 20 GW of renewable energy capacity could face connectivity delays during FY2026-27, while one in four major transmission schemes is already delayed by at least one year. The report suggested that around 3 GW to 4 GW of two-hour Battery Energy Storage Systems (BESS) could have absorbed most of the curtailed renewable power seen during the quarter. It also noted that nearly 236 GW of plug-and-play BESS headroom already exists at major pooling stations.
Industry experts increasingly believe that India’s renewable transition can no longer be planned through isolated targets for generation alone. The next phase of expansion, they argue, will depend on whether transmission, storage, grid operations and market design evolve together. For now, the country’s clean energy ambitions are running into a simple but costly constraint: electricity that can be generated but cannot yet be moved. |
