Battery storage is now cheap enough to enable solar power to meet as much as 90 per cent of India’s national electricity demand at a competitive levelised cost of electricity (LCOE) of Rs 5.06/kWh ($56/MWh) than current average power purchase costs (APPC) in most states, signalling a major shift in the country’s power economics, according to a new analysis.
The report, Battery storage is now cheap enough to unleash India’s full solar potential by Ember, a global energy think tank, estimates that achieving this will require around 930 gigawatt (GW) of solar capacity and 2,560 gigawatt-hour (GWh) of battery storage, which is equivalent to 4.9 GW of solar and 13.5 GWh of storage for every 1 GW of average demand. Even at this scale, only about 5 per cent of annual solar generation would need to be curtailed.
The findings come at a time when the Indian government expects the country’s peak power demand to reach a record 270 GW, even as a global energy crisis is unfolding. The US-Israel war against Iran has throttled global gas supplies, including from Qatar, India’s largest LNG supplier. While gas-based power was only 6.2 per cent of India’s electricity mix in the fiscal year 2024-25, the government has relied on it for meeting peak demand during short periods in the summer months. The government has often invoked Section 11 of the Electricity Act, 2003, to schedule maximum generation from gas-based stations to meet the peak summer demand. This year India will rely on coal, including imports, even as key benchmark prices of the fossil fuel are on the rise. The improving economics of solar plus batteries offer a natural buffer against such energy shocks in the future.
Additionally, solar is already expanding rapidly in India, and the country is struggling to scale up battery energy storage systems at the pace required to support its rapidly growing renewable energy capacity and deliver round-the-clock (24x7) power. Despite rising solar and wind additions, frequent renewable energy curtailment, especially in high-resource states like Rajasthan and Gujarat, reflects gaps in grid flexibility, transmission constraints and inadequate storage deployment.
While policy support has improved through viability gap funding and dedicated storage tenders, project execution remains slow due to high upfront costs, evolving market mechanisms, uncertainty around revenue streams and limited domestic manufacturing capacity. Discoms, already financially strained, have been cautious in signing long-term storage contracts, further delaying scale-up. As a result, India’s power system continues to rely on coal for balancing and peak demand, even as the need for flexible, dispatchable clean energy grows more urgent.
The report finds that the dramatic decline in battery costs is ready to unlock India’s vast solar potential, making round-the-clock solar electricity a viable and economically superior alternative to fossil fuels. Global turnkey battery costs fell by a massive 40 per cent in 2024, followed by another 31 per cent drop in 2025, and India has access to battery technologies at competitive costs.
“The dramatic improvement in battery economics over the past two years has delivered the missing piece that turns sunshine into reliable electricity day and night,” said Kostantsa Rangelova, global electricity analyst at Ember. “The question is no longer whether solar can power India’s electricity system, but how quickly it can scale.”
Solar installed capacity 143 GW of solar in FY26, accounting for 9.4 per cent of electricity generation in 2025, nearly doubling from 2022 levels. India’s estimated 3,343 GW of feasible ground-mounted solar potential is more than three times the capacity needed to meet 90 per cent of current demand, underscoring the scale of the opportunity.
At the state level, the economics are equally compelling. Solar-plus-battery systems could meet between 83 per cent and 92 per cent of electricity demand in the ten largest states, with seven states crossing the 90 per cent mark. In six of these, the modelled cost of electricity is already lower than current average power purchase costs, with savings of around 15 per cent on average.
The shift is being driven by a sharp fall in battery costs, which declined by 40 per cent in 2024 and a further 31 per cent in 2025. This has addressed a long-standing limitation of solar power (its inability to supply electricity after sunset) by enabling storage and dispatch of daytime generation into evening and night hours.
However, the transition is not without challenges. The Ember analysis identifies extended periods of low solar output, particularly during the monsoon, as the primary constraint. During such periods, solar and batteries together may meet only around 66 per cent of demand, highlighting the need for complementary generation sources. Seasonal and regional demand variations also affect performance, with states such as Uttar Pradesh and West Bengal facing greater mismatches between peak demand and solar availability.
The current power system also presents structural hurdles. Large-scale deployment would require significant expansion of transmission infrastructure to move solar power from high-resource states such as Rajasthan and Gujarat to demand centres. While transmission charges are currently partly mitigated by policy waivers, integrating high shares of solar and storage will require careful system planning and balancing mechanisms.
At the same time, the cost trajectory favours a faster transition. Recent solar-plus-storage auctions in India have discovered tariffs as low as INR 2.9-3.5/kWh, with a six-hour storage project in 2026 priced at Rs 3.12/kWh. In contrast, new coal power tariffs are rising to between Rs 5 and 6.3/kWh due to higher capital costs, fuel risks and environmental compliance requirements.
The analysis draws on hourly electricity demand data for 2024 from the India Climate and Energy Dashboard of NITI Aayog and solar generation data from the European Commission’s JRC PVGIS tool, modelling how solar and storage can match demand across hours, days and seasons.
The report also highlights that India has more than enough resources to become a global solar superpower while ensuring energy independence through local, inflation-proof resources. Beyond ground-mounted potential, India can further strengthen its energy security by tapping into 600 GW of residential rooftop solar and 300 GW of floating solar potential.
The findings of the report suggest that solar backed by battery storage can form the backbone of India’s electricity system, but not in isolation. A diversified mix including wind, hydro and other clean sources will be essential to manage seasonal variability, particularly during the monsoon. Scaling storage, strengthening grids and aligning policy frameworks will be critical to unlocking the full potential.
The results indicate that the question is no longer whether solar can power most of India’s electricity demand, but how quickly the system can adapt to make that transition feasible at scale.