The Transmission Corporation of Andhra Pradesh (APTRANSCO) has issued a request for selection for the development of 1,000 MW/2,000 MWh battery energy storage systems (BESS) across seven substations in the state.

Bids must be submitted by September 29, 2025. Bids will be opened on October 6.

The projects will be developed under the build, own, and operate model through tariff-based competitive bidding, with viability gap funding (VGF) support.

The VGF support available per project will be capped at ₹1.8 million (~$20,930.23)/MWh, disbursed in three tranches: 20% at financial closure and submission of bank guarantee, 50% at commercial operation date, and the remaining 30% upon completion of the first year of operations.

Bidders must furnish an earnest money deposit of ₹480,000 (~$5,581.40)/MW, a document fee of ₹50,000 (~$581.40) plus 18% GST.

The successful bidder must submit a performance bank guarantee of ₹1.2 million (~$13,953.49)/MW.

The bid processing fee ranges between ₹100,000 (~$1,168.63) and ₹750,000 (~$8,764.75) plus GST, depending on the project capacity.

The scope of work includes the development, operation, and maintenance of the standalone BESS projects at the designated substations. The projects must interconnect with the State Transmission Utility network at the 33 kV level.

The projects must ensure two operational cycles per day, with a minimum annual system availability of 95%. A round-trip efficiency of at least 85% is mandated, with penalties applicable for performance below this level and incentives for exceeding it.

Bidders must have a net worth of at least ₹3 million (~$34,883.72)/MWh of the quoted capacity, as of FY 2024-25 or at least seven days before bid submission. Bidders must also show a minimum annual turnover of ₹6 million (~$69,767.44)/MWh for FY 2024-25, excluding other income.

The projects must be commissioned within 18 months from the effective date of the battery energy storage purchase agreement, with a permissible extension of up to six months, subject to liquidated damages.

In case of performance shortfalls, penalties include liquidated damages equivalent to twice the capacity charges for availability below the mandated threshold. For round-trip efficiency shortfalls, no payment will be made if the efficiency drops below 70%. Levels between 70% and 85% will attract liquidated damages. Delays in commissioning will result in the encashment of the performance bank guarantee, along with penalties.

Recently, SECI issued a request for proposal for the development of a 600 MW/1,200 MWh standalone BESS in Kolimigundla in Nandyal district, Andhra Pradesh.