West Bengal State Electricity Distribution Company (WBSEDCL) has invited bids to set up 250 MW/1,000 MWh standalone battery energy storage systems (BESS) with an additional 250 MW/ 1,000 MWh under the greenshoe option at Goaltore substation, Paschim Midnapore.

Bids must be submitted by November 14, 2025. Bids will be opened on the same day.

Bidders must submit ₹500,000 (~$5,632) plus 18% GST as a document fee and ₹2,500 (~$28) plus 18% GST as a document processing fee.

They must also furnish ₹208,000 (~$2,343)/MWh plus 18% GST as earnest money deposit.

Selected bidders must submit ₹520,000 (~$5,857)/MWh as a performance bank guarantee at least seven working days before signing the battery energy storage purchase agreement (BESPA).

The BESS should be designed for interconnection with the WBSEDCL network at the 132 kV bus at the Goaltore substation.

Developers must guarantee AC to AC round-trip efficiency of 90% on a monthly basis.

Developers must use only commercially established and operational technologies to minimize the technology risk and to achieve timely commissioning.

The BESS must be commissioned within 18 months of signing the BESPA.

The BESPA will be signed for 15 years from the scheduled commissioning date.

Developers can take planned maintenance outages, but must give at least 1 month’s notice. The total planned outage time cannot exceed 34 hours in any two months.

Developers must state the maximum time needed to bring the BESS back to readiness between cycles. This must not be more than 1 hour.

The BESS must be designed to provide at least 4 hours of discharge at rated power.

WBSEDCL will not ask for more than one full 4-hour discharge per day at rated power. The 4 hours of charging can be done in one stretch or split into multiple sessions. The 4 hours of discharging can also be in one stretch or split into multiple sessions.

Charging or discharging may be at or below rated power, as WBSEDCL decides. The total energy discharged each day will be limited by the agreed round-trip efficiency of the energy supplied for charging.

After the bidding is over but before the project starts operating, if WBSEDCL finds that a viability gap funding amount is available, it will inform the developers. In that case, developers must agree to lower the winning tariff by ₹40,000 (~$450)/MW/month. Both parties will sign a short add-on agreement to record this change.

The net worth of the bidders should be at least ₹8.32 million (~$93,724) /MW, as of the last date of the previous financial year or at least seven days before the bid submission deadline.

Bidders must have a minimum annual turnover of ₹5 million (~$56,324) /MWh during the last completed financial year or as of at least seven days before the bid submission deadline.

In July, the Calcutta Electric Supply Corporation invited bids to set up a 40 MW/80 MWh standalone BESS in Kolkata, West Bengal, under the build, own, operate, and transfer model.

India added 48.4 MWh of energy storage capacity in the first half (1H) of 2025, a 74% decline from 186 MWh added in the same period last year, according to India’s Energy Storage Landscape 1H 2025 Report by Mercom India Research.