India requires around 10 GWh of battery energy storage system (BESS) capacity immediately to prevent renewable energy curtailment caused by the operational constraints of coal-fired power plants, according to a new analysis released by energy think tank Ember.
The report highlights that India curtailed nearly 2.1 TWh of renewable electricity during FY26 because coal-based generating units were unable to lower their output below minimum technical load (MTL) requirements. As a result, grid operators were often forced to reduce solar and wind generation despite the availability of low-cost clean energy.
According to Ember, the issue stems from the inflexibility of India’s coal fleet, which continues to provide the backbone of the country’s power system. Most coal plants are required to operate above a minimum load threshold, limiting their ability to accommodate fluctuations in renewable energy generation during periods of high solar and wind output.
The think tank estimates that deploying approximately 10 GWh of battery storage capacity could absorb excess renewable generation that would otherwise be curtailed. Stored energy could then be discharged during peak demand periods, improving grid flexibility and enhancing the utilization of renewable energy assets.
India has witnessed rapid growth in renewable energy installations over the past few years, with solar and wind power accounting for an increasing share of electricity generation. However, the expansion of renewable capacity has also highlighted the need for complementary investments in energy storage and grid modernization to maintain system reliability.
The report notes that battery storage can play a critical role in balancing supply and demand, reducing dependence on coal-fired flexibility, and minimizing renewable energy wastage. By storing surplus clean electricity during periods of high generation and releasing it when demand rises, BESS can help improve grid stability while supporting India’s clean energy transition.
The findings come as India accelerates efforts to deploy large-scale battery storage projects through government tenders and state-level procurement programs. Several gigawatt-scale storage projects are currently under development, reflecting growing recognition of storage as a key enabler of higher renewable energy penetration.
Ember emphasized that timely deployment of battery storage infrastructure will be essential for maximizing renewable energy utilization, reducing curtailment, and supporting India’s long-term targets for clean energy expansion and decarbonization.





