Written by PPL Newsroom• October 5, 2026• 12:04 pm• Innovation

SECI invites bids for 800 MW/3,200 MWh of standalone battery storage

The tender, SECI-ESS-IV, seeks four-hour batteries that distribution companies can call on when needed. Bids close on 30 October.

The Solar Energy Corporation of India (SECI) has issued a Request for Selection for 800 MW/3,200 MWh of standalone battery energy storage systems, to be procured through tariff-based competitive bidding. The tender, called SECI-ESS-IV, is meant to strengthen India’s storage capacity and help the power system absorb more renewable energy reliably. The document was issued on 1 October 2026.

What the tender asks for

The two figures describe different things. The megawatt number is how much power the batteries can deliver at any moment. The megawatt-hour number is the total energy they can supply over a full discharge. Capacity is to be quoted for four hours of charging and four hours of discharging in one cycle, which is how 800 MW becomes 3,200 MWh.

A bidder must submit one bid covering at least 50 MW/200 MWh and at most the full 800 MW/3,200 MWh. Procurement will be in energy (kWh) terms.

Ownership model: Projects will follow the Build-Own-Operate model and supply stored electricity on an on-demand basis.
Dispatch: The buying entity will schedule discharge for any four hours, starting from 17:00 on a given day and ending at 11:00 the next day.
Charging: Developers must ensure that at least 51% of the energy used to charge the batteries comes from renewable sources.
Technology and grid: The projects are technology-agnostic and can connect to the inter-state or state transmission network. The minimum voltage for inter-state connection is 220 kV.

How the process works

SECI will act as intermediary procurer. It will sign power purchase agreements with the selected developers, then sign back-to-back power sale agreements with the buying entities. Selection will use single-stage, two-envelope e-bidding followed by an electronic reverse auction.

The timeline is short. A pre-bid meeting is scheduled for 7 October, online submissions close on 30 October, and technical bids open on 4 November.

What this means for India

Solar power is plentiful in the day, but demand often peaks in the evening. This tender lets state power utilities and other buyers book batteries that discharge in the hours after sunset. It also requires that most of the charging energy be renewable. SECI has been moving in this direction for some time. In 2022 it issued what the government called a first-of-its-kind standalone storage tender of 500 MW/1000 MWh. This latest tender is larger and has longer-duration batteries. Results will show what developers charge for storage at this scale.

Background

In 2022, SECI tendered 500 MW/1000 MWh of standalone storage that discoms could use on an “on-demand” basis. The government’s release of that time cited a report projecting 27,000 MW/108,000 MWh of four-hour battery storage in the installed capacity mix by 2029-30.

SECI has other storage-linked tenders open this year. In June it invited bids for 1.2 GW of inter-state renewable projects coupled with storage, to deliver 4,800 MWh of assured peak power daily. In August it sought a 50 MW/100 MWh standalone system for short-term, on-demand use.

What happens next

After the bids are opened and the reverse auction is held, SECI will sign agreements with the winners. The discovered prices and the identity of the developers will only be known after that stage.