CESC Invites Bids For 40 MW/80 MWh Battery Storage Project At New Cossipore In Kolkata

CESC Limited, a power utility based in Kolkata, has invited bids for setting up a 40 MW/80 MWh standalone Battery Energy Storage System (BESS) project. The company issued a Request for Selection (RfS) on July 30, 2025. This project will be located at the New Cossipore Generating Station, situated at 28, Jheel Road, Kolkata – 700002. The selected developer will implement the project under the Build, Own, Operate, and Transfer (BOOT) model. After the agreement period ends, the project will be transferred to CESC at a token amount of INR 1.

The bidding process will be conducted through a single-stage, two-envelope e-tender system. Interested bidders must pay a non-refundable document fee of INR 29,500, which includes GST, and a document processing fee of INR 5,00,000 plus 18% GST per project. A key financial requirement includes an Earnest Money Deposit (EMD) of INR 6 crore, including GST. The EMD must be submitted in the form of a Bank Guarantee. In addition, selected bidders must submit a Performance Bank Guarantee (PBG) of INR 15 crore.

The timeline for the bidding process begins with the issue of the RfS on July 30, 2025. Site visits are scheduled from August 2, 2025, to August 17, 2025. A pre-bid meeting and technical clarification session will take place on August 25, 2025. The last date for submitting bids is September 18, 2025. The Letter of Award (LoA) is expected to be issued by or before October 28, 2025. After receiving the LoA, the Battery Energy Storage Purchase Agreement (BESPA) and the Right to Use Agreement for the project land must be signed within 30 days. The financial closure must be achieved within 270 days of signing the BESPA. The Scheduled Commissioning Date (SCD) for the complete capacity of the project is set at 540 days from the date of signing the BESPA.

The project is designed to support CESC’s load management operations through the use of BESS on a demand-based model. The technology to be used for the BESS is open, as long as it meets the required performance standards. The system should be able to deliver a useful energy output of 80 MWh at the delivery point and a peak power output of 40 MW. It must support up to two charge-discharge cycles daily for at least 12 years. The roundtrip AC to AC efficiency should be 90% on a monthly average basis, and the minimum system availability must be 95%.

The BESS will be connected to the CESC network at the 33kV Bus at the New Cossipore Substation. The selected developer will be responsible for all activities, including the design, engineering, procurement, construction, installation, testing, commissioning, operation, and maintenance of the complete system. The RfS document also includes detailed specifications for the battery subsystem, the energy management system (EMS), the battery management system (BMS), and the power conversion system (PCS). It also covers safety guidelines, performance testing, and environmental standards that must be followed during the project’s life cycle.