CTUIL Streamlines BESS Storage Capacity Enhancement Without Additional MW Connectivity

The Central Transmission Utility of India Limited (CTUIL) has issued an advisory outlining the procedure for enhancing the energy storage capacity of Battery Energy Storage System (BESS) projects that have already received connectivity approval. The guidelines apply to developers seeking to increase storage capacity measured in megawatt-hours (MWh) without increasing the approved charging or discharging power capacity measured in megawatts (MW).

Under the advisory, developers intending to enhance their BESS storage capacity while keeping the existing MW capacity unchanged must submit a formal application under Regulation 5.2 of the General Network Access (GNA) Regulations. Applicants are required to indicate nil additional MW capacity while clearly specifying the proposed increase in MWh storage capacity.

CTUIL has also clarified the applicability of connectivity bank guarantees under Regulation 5.2(e) of the GNA Regulations. The existing requirements for Conn-BG1 and Conn-BG3 remain applicable. However, since Conn-BG3 is generally calculated at ₹2 lakh per MW and the proposed enhancement does not involve additional MW capacity, CTUIL will approach the Central Electricity Regulatory Commission (CERC) to seek clarification on the requirement.

Pending CERC’s clarification, CTUIL will not demand Conn-BG3 immediately for such applications. However, developers will remain obligated to submit the applicable bank guarantee in accordance with any future directions issued by the commission. Failure to comply with these directions could lead to cancellation of the approval for additional MWh capacity and encashment of Conn-BG1.

To expedite the approval process, CTUIL will issue intimations reflecting the enhanced storage capacity once applicants fulfil all required regulatory compliances. Such applications will not require prior discussion in Central Monitoring and Evaluation of Transmission System (CMETS) meetings. Instead, the cases will be presented at subsequent meetings for information and noting.

The advisory also reiterates that developers must comply with all applicable requirements relating to land acquisition, financial closure, the Scheduled Commercial Operation Date (SCOD), and other provisions under the GNA Regulations and prevailing guidelines.

CTUIL has further confirmed that applications for MWh capacity enhancement submitted before the advisory’s issuance will also be processed under the newly established procedure. The guidelines provide a defined framework for developers seeking to increase storage duration without modifying their approved power capacity.