India Proposes Mandatory Battery Storage and Grid-Forming Inverters for New Solar and Wind Projects

The Central Electricity Authority (CEA), the technical arm of India''s Ministry of Power, published a draft notification on September 3, 2026 that would force nearly every new large solar and wind project in the country to be built with co-located battery storage and a minimum share of grid-stabilising inverter technology. If adopted, the rule would mark one of the most consequential regulatory shifts yet for how India''s renewable energy sector is engineered, shifting the cost and complexity of grid integration onto project developers rather than the grid operator.

What The Draft Rule Requires

The proposal takes the form of the draft Central Electricity Authority (Technical Standards for Construction of Electric Plants and Electric Lines) Second Amendment Regulations, 2026, issued under Section 177 of the Electricity Act, 2003 and published in the Gazette of India. Two requirements sit at its core. First, new ground-mounted solar and onshore wind projects commissioned on or after July 1, 2027 would need a co-located energy storage system with at least two hours of storage duration and a capacity equal to at least 10 percent of the plant''s installed capacity. Second, under a new Regulation 106B(20), at least 15 percent of the inverters at renewable power plants commissioned after that date would need to carry grid-forming control capability, and every power conversion system used in a battery storage installation would be required to have grid-forming capability built in, regardless of the plant''s size.

CEA has opened a public consultation window on the draft, inviting comments, suggestions and objections from developers, grid operators and other stakeholders through October 4, 2026, after which the authority can finalise, revise or withdraw the proposed regulation.

Grid-Following Versus Grid-Forming: Why The Distinction Matters

Almost all solar and wind inverters installed in India today are "grid-following" devices: they synchronise to a voltage and frequency reference that the grid itself, anchored historically by large spinning turbines at coal, gas and hydro plants, already provides. That works well as long as enough conventional generation remains online to set that reference. As renewables displace a growing share of that spinning-turbine capacity, grid operators increasingly worry about moments when there simply isn''t enough conventional inertia left on the system to hold voltage and frequency steady through a sudden fault or a large loss of generation.

Grid-forming inverters are designed to behave more like a spinning generator: rather than merely following the grid''s voltage and frequency, they can help establish and stabilise it, providing a synthetic form of the inertia that traditional turbines supply as a side effect of their physical mass. Regulators and grid operators in several markets with high renewable penetration have been moving toward requiring at least some grid-forming capacity for exactly this reason, and India''s proposed 15 percent threshold would put it among the more prescriptive jurisdictions globally on this specific requirement, reflecting how quickly the country''s renewable share has grown.

Curtailment Losses Are Part of the Backdrop

The storage mandate addresses a related but distinct problem: renewable energy curtailment, where generation that could otherwise be fed into the grid is deliberately throttled back because transmission capacity or demand cannot absorb it, typically around midday when solar output peaks. India''s power ministry and state utilities have documented repeated episodes of this kind in recent years, with solar and wind plants forced offline or throttled during periods of oversupply relative to what transmission lines and same-hour demand can handle. Requiring new projects to pair generation with on-site storage gives developers a way to shift some of that midday solar output into the evening peak instead of losing it outright, easing pressure on transmission corridors without necessarily building new lines.

The proposal follows CEA''s National Electricity Plan, which projected a need for roughly 208 gigawatt-hours of battery energy storage capacity by 2030 to support the pace of renewable capacity addition the government has targeted, and comes as India works toward its stated goal of 500 GW of installed non-fossil generation capacity by 2030 — a target that becomes considerably harder to hit reliably without a more resilient, storage-backed grid.

What It Means For Developers

For solar and wind developers, the immediate implication is cost. Co-located storage and grid-forming inverter hardware both add capital expenditure per megawatt that current projects, designed under the existing technical standards, do not need to absorb. Because the requirement applies only to plants commissioned from July 2027 onward, developers with projects already under construction or in advanced planning have a window to either accelerate commissioning ahead of the deadline or begin re-engineering designs to include storage and grid-forming inverters from the outset. Battery and inverter manufacturers serving the Indian market, meanwhile, stand to see a fresh source of guaranteed demand if the draft is finalised largely as written, reinforcing a battery-manufacturing push that the government has separately been trying to accelerate through production-linked incentive schemes.

Sources

• India's CEA proposes mandatory storage for new solar, wind projects from 2027
• CEA Proposes 15% Grid-Forming Inverters And Mandatory ESS For Renewable Projects From 2027
• CEA notifies draft CEA (Technical Standards for Construction of Electric Plants and Electric Lines) Second Amendment, Regulations, 2026
• CEA Proposes Mandatory Energy Storage for New Solar and Wind Projects From 2027
• Energy storage made mandatory for RE generation plants effective July 2027