India Proposes Mandatory Battery Storage for New Solar, Wind Projects From 2027

India plans to require battery storage at new government solar and wind projects from July 2027, under draft regulations aimed at making renewable power more reliable as the country's clean-energy capacity expands.

The proposal, prepared by the Central Electricity Authority (CEA), would require new solar and onshore wind projects commissioned after July 1, 2027, to install battery storage equivalent to at least 10% of their capacity for a minimum of two hours, according to Reuters.

The requirement would become stricter from July 2029, when the proposed minimum storage duration would rise to four hours while the 10% capacity threshold remains unchanged.

The draft rules reflect a growing challenge for India's renewable-energy system: solar and wind power do not generate electricity at a constant rate. Solar output falls after sunset, while wind generation can vary with weather conditions. Batteries can store electricity when generation is high and release it later, helping make power available when it is needed.

That challenge is becoming more pressing as India rapidly adds renewable capacity. Reuters reported that the country, now the world's third-largest solar power generator, curtailed nearly 14% of its solar output between April and June because of surplus daytime generation and limited transmission capacity.

In simple terms, some available clean electricity could not be used or moved through the grid when it was being generated.

Battery storage could help address that problem by absorbing surplus power and supplying it later. The proposed rules are also intended to improve grid stability as a larger share of India's electricity comes from renewable sources.

The draft regulations would additionally require clean-energy projects commissioned after July 2027 to include grid-forming inverter capabilities. These technologies can help maintain voltage and frequency on the electricity grid, a function that becomes increasingly important as conventional power plants play a smaller role in the energy mix.

The proposal is still in draft form, meaning the final rules could change before they are formally adopted.

If implemented as proposed, the policy would mark a significant shift for developers building new government solar and wind projects. Renewable-energy projects would no longer be assessed only on their ability to generate electricity; they would also need to account for how that electricity can be stored and delivered when generation drops.

For India's broader clean-energy ambitions, the proposal underlines a changing reality. Adding more solar panels and wind turbines is only one part of the transition. The next challenge is ensuring that the electricity they produce can reach consumers at the right time.

That could make battery storage an increasingly central part of India's renewable-energy build-out from 2027 onwards.