India Proposes 10% Storage Mandate for New Solar and Wind Projects From 2027

India’s Central Electricity Authority has proposed an India renewable energy storage mandate that would require qualifying new ground-mounted solar and onshore wind projects commissioned after July 1, 2027 to install co-located energy storage, a significant proposed change to the technical standards governing the country’s rapidly expanding renewable-power fleet.

Under the draft, storage capacity would have to equal at least 10% of a qualifying plant’s installed capacity and provide a minimum of two hours of storage. That means a 100 MW solar or onshore wind project would require at least 10 MW of storage capable of operating for two hours, equivalent to 20 MWh.

Storage duration would double from 2029

The Central Electricity Authority’s draft regulations would tighten the requirement for projects commissioned after July 1, 2029 and through June 30, 2031. Those projects would retain the minimum storage power requirement of 10% of installed renewable capacity, but the required duration would increase from two hours to four hours.

For a 100 MW renewable project, the later requirement would therefore translate into at least 10 MW/40 MWh of co-located storage. The proposal remains a draft rather than a final mandate, with stakeholders and the public invited to submit comments through October 4, 2026.

The approach would extend India’s growing emphasis on pairing renewable generation with dispatchable resources. Microgrid Media recently covered Tata Power Renewable Energy’s 190.5 MW Rajasthan firm and dispatchable renewable energy project, which combines utility-scale solar generation with 115 MWh of battery storage.

Grid-forming inverters are another major part of the proposal

The India renewable energy storage mandate is only one part of the proposed technical changes. Renewable-energy plants commissioned after July 1, 2027 would also be required to have at least 15% of their inverters equipped with grid-forming control, according to PV Tech’s review of the draft.

The proposal also calls for all power conversion systems used in battery energy storage systems to have grid-forming control that complies with applicable grid-connectivity technical requirements.

Grid-forming capability is increasingly important as power systems add larger quantities of inverter-based generation. Unlike conventional grid-following inverters, grid-forming systems can actively establish and support voltage and frequency rather than simply following an existing grid waveform.

The distinction is also relevant to smaller distributed systems. Microgrid Media’s guide to microgrid controllers and grid-forming inverters explains how grid-forming equipment and supervisory controls perform different but complementary functions when coordinating generation, storage and electrical loads.

India is trying to make renewable generation more dispatchable

The proposed requirements arrive as India’s electricity system absorbs rapidly increasing quantities of solar generation. Reuters reported on September 4 that India curtailed nearly 14% of its solar generation between April and June as daytime renewable output exceeded what could be absorbed or transported in some periods.

Storage can reduce that mismatch by charging when renewable generation is abundant and releasing electricity later when demand is stronger or renewable output declines. It can also provide grid services that become increasingly valuable as conventional synchronous generation represents a smaller share of the generation mix.

The policy direction is already visible at the state level. Maharashtra’s renewable-energy framework, for example, includes storage requirements for new contracted renewable projects, a connection reflected in Microgrid Media’s coverage of the Ekrukh floating solar and battery project.

The proposal is not yet a final rule

The CEA’s action should not yet be described as an enacted storage mandate. The technical requirements are currently proposed amendments and remain subject to consultation and finalization.

If adopted substantially as drafted, however, the rules would move co-located storage and grid-forming capability deeper into the technical requirements for new renewable plants rather than treating batteries simply as optional additions to solar and wind developments.

For developers, that would make storage sizing, inverter architecture and grid-support capability increasingly important considerations at the design stage. For the power system, the broader objective is to make a rapidly growing renewable fleet more controllable and better able to support grid stability as India’s electricity mix changes.