India Mandates Battery Storage for Solar and Wind Projects

This regulatory shift addresses a persistent gap between India’s rapid renewable energy expansion and its aging transmission infrastructure. Currently, the national grid frequently rejects surplus power during peak generation hours, forcing developers to curtail output. Data from the think tank Ember shows that grid constraints accounted for nearly two-thirds of all renewable curtailment—roughly 300 gigawatt-hours—during the first quarter of this year.

The mandate introduces a tiered implementation schedule. Initially, projects commissioned after July 2027 must provide two hours of storage. This requirement tightens significantly for facilities commissioned between 2029 and 2031, which will be obligated to maintain a minimum duration of four hours. Ministry of New and Renewable Energy Secretary Santosh Sarangi noted that developers have already begun adopting these measures voluntarily to ensure their power remains marketable to grid operators.

Ember analysts estimate that the country requires an immediate 10 gigawatt-hours of storage to prevent waste when coal-fired plants cannot reduce their output further. By forcing integration at the site level, the government hopes to decouple the renewable boom from transmission bottlenecks that threaten to stall India's clean energy transition.