Curtailment Concerns: Need to focus on effective power delivery, not just expansion

This article is written by Ratul Puri, Chairman, Hindustan Power

From April 1, 2025 to March 31, 2026, India added over 54 GW of renewable capacity. However, a substantial part of renewable energy was curtailed due to grid security concerns and transmission constraints. As per Ember, 300 GWh of renewables was curtailed due to transmission constraints in the first quarter of 2026. Thus, the significant achievement of building extra renewable capacity was subdued by curtailment. No doubt there were mitigating circumstances last year, such as muted power demand and limited storage capacity. Nonetheless, the scenario highlighted a basic truth – renewable energy cannot be scaled without grid modernisation and flexibility. As India transitions steadily towards a solar-enabled future, storage solutions based on flexibility will be indispensable.

Prioritising power delivery

Installed capacity and delivered power are not the same thing. The country has undeniably built scale by boosting generation capacity, particularly based on renewables and non-fossil fuel power. Yet actual output continues to be constrained by curtailment, transmission bottlenecks, grid limitations and despatch inefficiencies. As the power system matures, efficiency, reliability and delivered output matter more than just capacity announcements.

Therefore, the next challenge lies in ensuring that installed capacity is effectively evacuated, despatched and utilised. The real measure of India’s renewable progress will no longer be based on how many megawatts are built. Rather, it will depend on how many megawatts deliver value to the electricity network. As the economy grows, electricity demand keeps rising across homes, industries, services and agriculture. Meeting this burgeoning demand entails higher power generation backed by a system that can effectively deliver it across the entire country. Accordingly, India’s generation capacity is being steadily expanded via conventional and renewable sources. During 2025-26, 52,537 MW of generation capacity was added across all sources, as of January 31, 2026. Of this, renewables accounted for 39,657 MW, with 34,955 MW of solar and 4,613 MW of wind power capacity. For a single year, this represents the highest capacity addition.

Curtailment concerns

Nevertheless, the spoke in the wheel is the fact that renewable capacity is outpacing the system’s ability to absorb it. For the clean energy mission to become a ground-level success, it is imperative that renewable curtailment, despatch delays and the lack of large-scale storage are addressed on a war footing. In states such as Gujarat and Rajasthan with high renewables, curtailment has emerged as a major issue. When the growth in demand slows or infrastructure is lacking, these operational and physical constraints hinder the absorption of renewables. Rather than low demand or generation capacity, curtailment occurs due to system balancing, transmission and storage issues. As per a January 2026 report by Ember, India curtailed 2.3 TWh of solar power between May and December 2025. This was because the grid could not manage rising daytime generation and weak demand, despite the historic expansion of renewables. Instead of replacing fossil fuel generation, solar output had to be curtailed to safeguard grid stability. The curtailed electricity would have been sufficient to power almost 400,000 households for a year.

Addressing transmission, grid stability and variability issues

Another emerging growth area is grid stability. The rising penetration of renewables has led to variability-linked fluctuations in India’s integrated national grid. Addressing this requires stringent compliance with technical norms and better system flexibility.

Owing to the increasing adoption of renewables, variability and grid stability issues can arise. To address these challenges, flexible storage solutions remain the need of the hour. As per a CRISIL-FICCI report on India’s energy transition, energy storage systems, battery energy storage systems (BESSs), pumped hydro storage (PHS) and thermal energy storage will be critical to ensuring reliable and sustainable power supplies. With these technologies, excess renewables can be stored and despatched whenever required. This will facilitate the delivery of consistent, round-the-clock renewable energy while maximising grid infrastructure and operational efficiencies.

Against this backdrop, PHS is poised to emerge as a pivotal pillar in handling large-scale balancing capacity. In view of the intermittency linked to renewables, the government is promoting a mix of energy storage and hybrid solutions to support reliable power supplies through grid stability. Besides, the Central Electricity Regulatory Commission has introduced solar-hour and non-solar-hour connectivity, enabling full use of transmission infrastructure while promoting hybrid renewable projects that combine solar, wind and BESSs.

Given these challenges, India’s next power sector benchmark should be utilisation rather than just installation.