Draft technical standards propose 10% storage capacity for new ground-mounted solar and onshore wind projects, with storage duration increasing to four hours from July 2029
The Central Electricity Authority (CEA) has proposed a significant change in the technical requirements for new renewable energy projects, with co-located Energy Storage Systems (ESS) set to become a proposed requirement for qualifying ground-mounted solar and onshore wind projects from July 2027.
The proposal is contained in the Draft Central Electricity Authority (Technical Standards for Construction of Electric Plants and Electric Lines) 2nd Amendment Regulations, 2026, published by CEA on September 3, 2026. The draft has been issued for public comments, with stakeholders invited to submit their objections and suggestions by October 4, 2026.
10% Co-Located Storage Proposed from July 2027
Under the draft proposal, ground-mounted solar power plants and onshore wind power plants commissioned after July 1, 2027 would be required to have a co-located ESS with a minimum storage duration of two hours.
The storage capacity would need to be equivalent to at least 10% of the installed capacity of the renewable energy plant.
For example, a 100 MW solar or wind project would require at least 10 MW of co-located storage, with a two-hour duration, equivalent to 20 MWh of storage.
The proposed requirement would therefore introduce storage directly into the technical design of qualifying renewable projects rather than treating it only as a separate procurement or tender requirement.
Storage Duration Proposed to Increase from 2029
The draft proposes a further increase in the minimum storage duration for projects commissioned after July 1, 2029 and up to June 30, 2031.
During this period, the storage capacity requirement would remain at 10% of the plant’s installed capacity, but the minimum storage duration would increase from two hours to four hours.
For a 100 MW renewable project, this would translate into at least 10 MW/40 MWh of co-located ESS.
| Project commissioning period | Proposed ESS capacity | Minimum duration | Example for 100 MW plant |
| After July 1, 2027 | 10% of installed capacity | 2 hours | 10 MW / 20 MWh |
| July 1, 2029 – June 30, 2031 | 10% of installed capacity | 4 hours | 10 MW / 40 MWh |
Grid-Forming Inverters Also Proposed
The draft also introduces requirements related to grid-forming capability.
Renewable energy power plants commissioned after July 1, 2027 would be required to have at least 15% of their inverters equipped with grid-forming control.
In addition, the proposal requires the power conversion systems (PCS) used in battery energy storage systems to have grid-forming capability in accordance with the applicable grid-connectivity requirements.
This would increase the emphasis on inverter-based resources that can provide stronger grid-support capabilities as India’s power system integrates increasing levels of variable renewable generation.
Implications for Renewable Project Design
If adopted in its proposed form, the regulation could have significant implications for the planning and economics of future renewable projects.
Developers would need to account for co-located storage during project design, potentially affecting land requirements, electrical architecture, inverter and PCS selection, energy management systems, capital expenditure and project scheduling.
The proposal could also accelerate the integration of solar and wind generation with battery storage, creating additional demand for BESS equipment and grid-forming technologies.
For renewable projects commissioned after the proposed dates, storage would effectively become part of the plant’s technical configuration rather than an optional enhancement.
Proposal, Not Yet a Final Mandate
The CEA’s announcement is currently a draft regulation and should not be treated as an already enforceable storage mandate.
The official CEA website lists the draft under its Draft Regulations section and confirms that public comments are being invited until October 4, 2026. The final requirements could therefore change following the consultation and regulatory process.
The proposal nevertheless marks a significant shift in India’s renewable-energy framework by linking new solar and wind generation more closely with energy storage and grid-forming capabilities.
Source: Central Electricity Authority (CEA), Government of India — Draft CEA (Technical Standards for Construction of Electric Plants and Electric Lines) 2nd Amendment Regulations, 2026:
CEA — Draft Regulations / Official Publication
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