India’s clean energy push is increasingly being shaped by three structural pressures: renewable curtailment, transmission delays and the urgent need for large-scale energy storage.
Acknowledging it, Ghanshyam Prasad, chairperson of the Central Electricity Authority (CEA), at the India Energy Transition Summit by the Federation of Indian Chambers of Commerce and Industry (FICCI), said renewable capacity is expanding faster than the system’s ability to absorb it, creating localised curtailment in key renewable hubs and exposing infrastructure constraints that must be addressed to sustain growth.
Curtailment has surfaced most prominently in high-renewable states such as Rajasthan and Gujarat. Early project developers who brought capacity online ahead of grid readiness, have faced temporary restrictions on power evacuation, with several gigawatts of renewable output affected at different points.
Prasad emphasised that the issue is not due to a lack of demand or generation capacity, but stems from system balancing limits, transmission readiness, and storage shortages.
“Renewable absorption faces physical and operational constraints when demand growth slows or infrastructure lags,” he noted, adding that curtailment remains a transitional challenge rather than a structural barrier to expansion.
India curtailed 2.3 terawatt-hours (TWh) of solar power between May and December 2025 despite record renewable expansion, as the grid struggled to handle rising daytime generation and weak demand growth, according to a January 2026 report by global energy think tank Ember.
The report, Beyond Capacity: Why India’s Power System Must Get Flexible, says the curtailed electricity — enough to power nearly 400,000 homes for a year — reflects a widening gap between clean energy growth and system flexibility. India added a record 38 GW of solar capacity in 2025, lifting non-fossil fuel sources to 50 per cent of installed power capacity. Yet instead of replacing fossil generation, some solar output was switched off to maintain grid stability.
The main constraint was limited operational flexibility in coal plants, which must run above a minimum technical load of 55 per cent, preventing them from ramping down during periods of high solar output and low daytime demand.
Transmission constraints are compounding the problem. Developers say inadequate grid infrastructure has left several commissioned renewable plants unable to fully evacuate power, forcing output cuts and financial losses. Industry sources told Down To Earth (DTE) before that at least 30 solar and wind projects faced curtailment between March and August 2025, with losses estimated at up to Rs 700 crore — a trend experts warn could undermine investment confidence and threaten India’s 500 GW non-fossil capacity target for 2030.
The Union Ministry of Power oversees transmission approvals, while projects require general network access from the Central Electricity Regulatory Commission to operate fully. However, several new plants in Rajasthan, Gujarat, Maharashtra and Tamil Nadu have only received temporary network access, allowing power injection only when transmission lines are uncongested.
Developers earlier told DTE the Grid Controller of India has instructed some projects to curtail up to 48 per cent of daily generation during constrained periods, underscoring the growing urgency of grid expansion, storage deployment and system flexibility reforms.
Financial institutions are also closely monitoring curtailment risks, Prasad said, as they influence investment confidence in large-scale renewable deployment.
Transmission infrastructure is emerging as the critical enabler and potential bottleneck for India’s next phase of energy transition.
The country has adopted potential-based transmission planning to align infrastructure with renewable growth, but implementation timelines are increasingly affected by right-of-way challenges and project execution constraints. Transmission project timelines may need to extend from roughly two years to as much as three years to reflect ground realities.
New categories of electricity demand, particularly hyperscale data centres, are also reshaping grid planning standards. Unlike conventional consumers, these facilities require dual supply sources and high-reliability configurations from the outset, adding complexity to system design.
Grid stability is another growing concern. Rising renewable penetration has introduced variability-driven oscillations across the integrated national grid, underscoring the need for stricter adherence to technical standards and improved system flexibility.
Energy storage is emerging as a central pillar of India’s long-term power system architecture as the country advances toward its target of 500 GW of renewable energy capacity by 2030. Large-scale deployment of solar and wind power introduces variability and grid stability challenges, making flexible storage solutions indispensable.
A report, Energy Storage for India’s Energy Transition, released by CRISIL and FICCI on February 26, acknowledges that energy storage systems (ESS), including battery energy storage systems (BESS), pumped hydro storage (PHS), and thermal energy storage (TES), are essential enablers of a reliable and sustainable power supply. These technologies allow surplus renewable energy to be stored and dispatched when required, helping deliver firm, round-the-clock renewable power while optimising grid infrastructure and operational efficiency.
Within this framework, pumped hydro storage is positioned as the backbone of large-scale balancing capacity. Policymakers and system planners emphasise its role as a stable, long-duration solution capable of supporting grid resilience at scale.
Prasad highlighted plans to integrate around 100 GW of pumped hydro storage within the next decade, describing it as the preferred large-scale balancing solution due to its stability and system support capabilities. Identified hydro storage potential has expanded significantly in recent years, supported by policy reforms and private-sector participation.
Pumped hydro’s ability to provide bulk energy shifting, peaking power, and system inertia makes it particularly suited to managing variability from high renewable penetration levels and maintaining grid reliability over extended durations.
Battery energy storage is expected to play a complementary role alongside pumped hydro, offering fast-response capabilities and flexible deployment where large infrastructure solutions are not feasible. While batteries are critical for ancillary services, peak shaving, and localised grid support, planners generally view them as secondary to pumped hydro for long-duration system balancing.
At the same time, large-scale storage deployment across both hydro and battery technologies is increasingly necessary to manage rising system costs associated with renewable integration, including balancing requirements, reserve margins, and grid stability investments. These system-level costs extend beyond headline renewable generation tariffs, reinforcing the strategic importance of storage as a foundational component of India’s clean energy transition.