POWERGRID Issues EPC Tenders for 750 MW / 3,000 MWh Battery Energy Storage Systems in West Bengal

Power Grid Corporation of India Limited (POWERGRID) has invited bids for the establishment of standalone Battery Energy Storage Systems (BESS) across multiple locations in West Bengal. The procurement, totaling a cumulative capacity of 750 MW / 3,000 MWh, is distributed across five strategic projects intended for “On-Demand” usage. Utilizing a Tariff-Based Competitive Bidding (TBCB) process, these systems will be embedded in the West Bengal State Electricity Distribution Company Limited (WBSEDCL) distribution network to provide critical grid flexibility, mitigate renewable energy intermittency, and support peak load management during non-solar hours.

BESS Capacity Allocation by Location

The projects are situated at specific State Transmission Utility (STU) substations, with the delivery point defined at the bus bar of the respective sites. All systems are required to provide a minimum four-hour discharge duration.

Tender Procedural Details & Logistics

The administrative and financial requirements for bidders are detailed as follows:

• Bid Submission Deadlines: Online bid submission for four tenders closes on June 22, 2026, while the remaining tender deadline is June 23, 2026.
• Bidding Portals: Bidders must use the PRANIT e-tendering portal for specific POWERGRID packages and the TCIL portal for aggregated RfS submissions.
• Tender Fees: A non-refundable fee of ₹25,000 is applicable for the Goaltore package. The 500 MW aggregated RfS requires a document fee of ₹5 Lakh plus 18% GST.
• Earnest Money Deposit (EMD): Bidders must furnish an EMD of ₹3 Lakh per MWh of quoted capacity, capped at a maximum of ₹10 Crores.
• Performance Bank Guarantee (PBG): Successful bidders are required to submit a PBG valued at ₹7.5 Lakhs per MWh prior to signing the BESPA.
• Electronic Reverse Auction (e-RA): Selection will conclude with an e-RA among techno-commercially qualified bidders to determine the final Monthly Capacity Charges.

Technical Scope and Performance Requirements

Developers are mandated to adhere to strict technical parameters to ensure grid stability and system longevity:

• Scope of Work: Comprehensive responsibility for design, engineering, supply, testing, installation, and commissioning, followed by 15 years of Operation & Maintenance (O&M).
• Asset Model: Projects will be developed on a Build-Own-Operate (BOO) basis.
• Land Logistics: Land is provided on a “Right-To-Use” basis by WBSEDCL at a nominal annual rent of ₹1/- per project.
• Performance Metrics: Guaranteed AC-to-AC Round-Trip Efficiency (RtE) of 85% and a minimum monthly system availability of 95%. Shortfalls in availability will incur liquidated damages at twice the Capacity Charges for the unavailable portion.
• Duty Cycle & Recovery: The BESS must support one complete charge-discharge cycle per day with a minimum 4-hour discharging capacity at rated power. The system must achieve a maximum recovery time of 1 hour between duty cycles.
• Capacity Degradation: The minimum dispatchable capacity is expected to follow a graduated degradation schedule, starting at 97.5% in Year 1 and maintaining at least 70% from Year 12 through Year 15.
• Auxiliary Power: The developer is responsible for securing a separate metered connection for auxiliary power from WBSEDCL at their own cost.

Institutional Roles and Coordination

The procurement involves distinct roles for state and central entities:

• Department of Power, Govt. of West Bengal: Acts as the overarching Bidding Agency managing the process for the 500 MW aggregated capacity.
• West Bengal State Electricity Distribution Company Limited (WBSEDCL): The designated off-taker and the beneficiary of the “On-Demand” capacity. WBSEDCL is responsible for providing charging energy.
• POWERGRID: Serves as the developer/applicant and the specific tender inviter for individual packages, such as WB-BESS-05 (Goaltore).
• West Bengal State Electricity Transmission Company Limited (WBSETCL): The State Transmission Utility (STU) providing the physical substation connectivity and evacuation infrastructure.

Project Implementation Timeline

Milestones are calculated relative to the Effective Date, defined as 30 days from the issuance of the Letter of Award (LoA) or the date of signing the BESPA, whichever occurs earlier.

1. Document Verification: Submission of all required documentation within 15 days of LoA issuance.
2. Signing of BESPA: Execution of the Battery Energy Storage Purchase Agreement within 30 days of LoA issuance.
3. Financial Closure: Reporting of 100% tie-up of project financing within 9 months from the Effective Date.
4. Scheduled Commissioning Date (SCD): Full project commissioning is required within 18 months from the Effective Date.