Transmission Constraints Threaten India’s Renewable Energy Expansion
Subject: GS III – Economy; Environment & Renewable Energy.
Context & Background
While India continues to scale up its green energy footprint—boasting over 150 GW of renewable energy projects under construction—transmission bottlenecks have emerged as a critical threat to the sector’s long-term viability.
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The Core Crisis: Solar and wind projects are increasingly facing curtailment—the forced reduction or shutdown of electricity generation due to oversupply, grid congestion, and a lack of transmission capacity.
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The Scale of the Problem: Approximately 37% of renewable capacity at curtailment-affected substations across northern, western, and southern India operates under Temporary General Network Access (T-GNA). These projects suffer a staggering 30% to 50% daytime curtailment, severely eroding revenues and escalating operational costs. Peak curtailment touched 8,617 MW in western India and 5,573 MW in the northern region.
Understanding Temporary General Network Access (T-GNA)
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What it is: T-GNA is a short-term regulatory mechanism that permits renewable energy projects to access available transmission capacity on the inter-State transmission system (ISTS) for durations ranging from a single time block up to 11 months.
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The Vulnerability: Because T-GNA relies on surplus or temporary grid availability rather than dedicated long-term transmission access (LTA), projects dependent on it are the first to be throttled when grid congestion peaks.
Key Structural Bottlenecks Identified by ICRA
Rating agency ICRA and sector analysts have highlighted several interconnected roadblocks slowing India’s energy transition:
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Grid and Storage Deficits: Inadequate inter-State and intra-State transmission infrastructure, compounded by a lack of large-scale energy-storage systems (BESS/pumped storage) required to absorb intermittent generation and stabilize the grid.
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Plummeting Bid Activity: Investor confidence is waning due to grid adequacy concerns. Renewable capacity awarded through bids dropped precipitously from 40.6 GW in FY 2024–25 to 14.7 GW in FY 2025–26, and a modest 4.7 GW by August 2026.
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PPA Deadlocks: As of April 2026, roughly 40 to 45 GW of awarded capacity remained without signed Power Purchase Agreements (PPAs), underscoring severe execution delays.
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DISCOM Fragility: The continued weak financial health of state distribution companies (DISCOMs) creates payment security risks and discourages timely off-take.
Paradigm Shift: Moving Towards FDRE and RTC Power
To overcome the intermittency of traditional solar and wind power, the energy market is shifting toward advanced, reliable supply models:
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Firm and Dispatchable Renewable Energy (FDRE): Power that can be reliably supplied on demand. It bundles variable solar/wind assets with battery storage or complementary sources to match grid load curves precisely when required.
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Round-the-Clock (RTC) Renewable Power: A model ensuring continuous $24\times7$ electricity supply.
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Example: A hybrid project combining solar power (stored in batteries for night use), wind energy, and pumped-storage hydro can compensate for low solar output, providing predictable, baseload-like green power.
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Way Forward: Securing the Green Transition
To meet India’s ambitious climate targets (such as achieving 500 GW of non-fossil capacity and net-zero by 2070), structural interventions are urgently required:
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Fast-Tracking Transmission Infrastructure: Accelerating green energy corridors through coordinated planning between Central and State transmission utilities.
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Mandating Storage Integration: Scaling up battery energy storage systems (BESS) and pumped-storage hydroelectric projects (PSPs) to tackle grid frequency and congestion issues.
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Streamlining Contracting: Enforcing strict timelines for PPA execution and reinforcing DISCOM financial reforms to restore investor confidence.
