India Lost Significant Solar Power Generation Due to Grid Curtailment in 2025

India’s growing solar energy output was significantly reduced last year because grid operators had to cut back production to maintain system stability, according to a new report by energy think-tank Ember. From late May through December 2025, around 2.3 terawatt-hours (TWh) of potential solar generation was curtailed — energy that could have powered millions of homes and reduced greenhouse gas emissions — due to operational limits on the electricity grid.

The Ember analysis shows that this curtailed solar power amounted to roughly 18% of the average monthly solar generation during the period. Grid operators were forced to cut solar output when electricity demand was lower than expected and other power sources, particularly coal plants, could not be turned down further without risking grid security. Because of this, emergency procedures were used to reduce solar output to keep the grid stable.

The report highlights that the rapid addition of solar capacity — about 38 GW in 2025 — exposed weaknesses in the grid’s ability to integrate large amounts of variable renewable energy. A significant share of the curtailment is linked to transmission bottlenecks and limited operational flexibility of other power plants, which makes it difficult to absorb midday solar production when demand is low.

Solar generators affected by emergency curtailment received financial compensation under existing reserve mechanisms, amounting to an estimated INR 5,750 million to INR 6,900 million (approximately USD 63 million–76 million). Besides this direct cost, the report notes an environmental loss: the curtailed solar generation could have avoided about 2.1 million tonnes of CO₂ emissions if it had displaced coal-fired electricity.

Looking forward, Ember argues that India must improve grid flexibility alongside continued growth in renewable capacity. The report recommends enhancing the ability of conventional generators to adjust output, expanding energy storage solutions, and promoting demand-side measures that shift electricity use to times of high renewable generation.