The Central Electricity Regulatory Commission (CERC) has recently notified the Connectivity and General Network Access to the Inter-State Transmission System (Third Amendment) Regulations, 2025, introducing reforms towards securing grid access. The amendment refines the regulatory framework established under the 2022 principal regulations, seeking to align it with the growing share of renewable energy, hybrid generation, and storage projects in India’s power system. It expands the scope of connectivity to include clusters of ISTS substations, the terms “connectivity guarantees” and “host regional load despatch centre (RLDC)”; introduces differentiated access during solar and non-solar hours; integrates new transmission zones under the interstate network; and rationalises procedures for withdrawal, reallocation, and monitoring of connectivity.
In line with the country’s rapidly diversifying generation mix, the amendment aims to ensure an agile and responsive grid access framework.
Objective
The amendment aims to strengthen the general network access (GNA) framework by improving coordination, predictability, and transparency in managing renewable energy sources. It addresses procedural and operational challenges by introducing clearer processes and a flexible scheduling mechanism that distinguishes between solar and non-solar hours. This approach would allow developers to align generation with actual grid availability, enhance utilisation, and reduce idle capacity.
The commission has also reinforced compliance and monitoring to ensure that connectivity is allocated efficiently and supported by tangible project progress.
Key definitions introduced
One of the significant additions in the amendment is the definition of a “cluster of ISTS substations”. Under this, substations that are geographically or electrically proximate may be grouped and declared by Central Transmission Utility of India Limited (CTUIL) as a cluster, enabling inter-substation flexibility in allocation or reallocation of connectivity. This cluster-based approach recognises the spatially concentrated nature of renewable energy projects and is designed to maximise the utilisation of available bays and infrastructure.
The amendment also introduces a number of key operational definitions in line with the new scheduling framework. “Solar hours” and “non-solar hours” are now defined as time blocks determined weekly by the National Load Despatch Centre based on forecasted solar insolation. Correspondingly, “solar hour access” allows injection scheduling rights during solar hours, while “non-solar hour access” provides scheduling rights during non-solar hours. These categories acknowledge the variable character of renewable energy sources and enable developers to seek connectivity aligned with their generation profile.
Other inclusions, such as “connectivity grantee” and “host RLDC”, further streamline institutional responsibilities. The term “connectivity grantee” refers to any entity that has received a final grant and signed the connectivity agreement, while the term “host RLDC” signifies the regional centre responsible for operational coordination with entities within its geographical area. Together, these definitions enhance the procedural clarity of the regulatory text and promote uniformity across agencies and projects.
Revised connectivity provisions
A major portion of the amendment revises Regulation 3.7 of the principal regulations concerning the withdrawal of applications and the treatment of bank guarantees. The new provisions introduce a graded approach depending on the stage of the application. Withdrawals made before the in-principle grant will result in a forfeiture of 50 per cent of the application fee, while withdrawals after the in-principle or final grant will incur a higher forfeiture of both the application fees and the bank guarantee value.
Further, the amendment allows applicants to make equivalent online payments instead of physically encashing bank guarantees in certain cases, enabling faster settlement. It also establishes timelines for the nodal agency to return uncashed guarantees or release land documents following withdrawals, typically within 15 days.
The new regulations introduce flexibility for partial withdrawals in cases where the transmission capacity is unavailable for the full quantum sought, provided the remaining capacity meets the minimum threshold. By allowing partial continuation instead of requiring fresh applications, the commission has reduced administrative redundancy while safeguarding system adequacy.
Integration of BBMB network and small-scale projects
Another important feature is the inclusion of the Bhakra Beas Management Board (BBMB) system as part of the interstate transmission network. Projects seeking connectivity to the BBMB grid, including renewable generating stations (REGS) and energy storage systems (ESS), can now apply under a specified procedure. Renewable energy projects with a capacity between 5 MW and 50 MW may seek connectivity through the BBMB substations, while those below 5 MW owned or selected by the BBMB can apply through the state load despatch centre. The amendment also exempts very small projects from certain financial and documentation requirements, such as bank guarantees and one-time GNA charges, recognising their limited grid impact.
Expanded provisions for renewable, hybrid, and storage projects
The amendment allows renewable energy generating stations with storage to declare both their maximum injection and maximum drawal requirements within the granted connectivity quantum. Similarly, standalone storage systems can now apply for connectivity based on whichever is higher – maximum injection or maximum drawal from the ISTS. This dual-capacity framework provides greater operational autonomy for charging and discharging cycles without requiring separate connectivity for each function.
For hybrid developers, the new provisions formalise differentiated access rights. Entities based on solar sources are categorised as having solar hour access, whereas those based on wind or storage fall in the category of non-solar hour access. In the case of renewable-hybrid generating stations (RHGS) combining solar, wind, and storage, the regulation defines how injection rights will vary across time blocks. This granular treatment acknowledges the technical reality that hybrid stations may operate with varying combinations of resources throughout the day.
The amendment also allows existing solar-based projects to be converted into entities with solar hour access within a specified transition period, ensuring consistency in scheduling. At the same time, projects where non-solar access availability is below 50 MW will continue to have full-day access, preventing unnecessary administrative reclassification.
Procedural and financial rationalisation
The amendment introduces a new lower voltage category of less than 132 kV with a corresponding connectivity bank guarantee of Rs 10 million, thus expanding eligibility for smaller projects. It also revises the treatment of bank guarantees under different stages of connectivity and specifies that guarantees may be issued by any scheduled commercial bank recognised by the Reserve Bank of India.
Timelines for signing connectivity agreements have been tightened. Entities receiving final connectivity must sign the agreement within 30 days, failing which the grant may be revoked. Similarly, the nodal agency must communicate coordinates, terminal bay locations, and single line diagrams within defined periods, ensuring that developers have certainty for construction planning.
Another key change concerns the treatment of additional generation capacity within an existing connectivity quantum. Developers can now add new capacity or storage within the same connectivity limits, subject to compliance with grid codes and the payment of relevant bank guarantees, but without requiring augmentation of the transmission system. This provision facilitates the efficient use of existing assets while allowing incremental capacity addition.
Reallocation and monitoring mechanisms
To ensure optimal utilisation of the transmission network, the amendment introduces a cluster-based reallocation mechanism. If a terminal bay at an ISTS substation becomes vacant due to the withdrawal or revocation of connectivity, the CTU may reallocate it to another project within the same cluster. This approach allows quicker reassignment of infrastructure and prevents prolonged idling of bays. The reallocation will be prioritised based on the chronological order of original applications, ensuring fairness among applicants.
The amendment also strengthens post-approval monitoring. The nodal agency must now publish compliance details of land and financial closure milestones for all connectivity grantees, while RLDCs are required to monitor the actual utilisation of granted connectivity and GNA. The NLDC will compile quarterly utilisation reports and propose remedial measures for non-optimal usage. These steps will address a long-standing concern that many entities held grid access without progressing towards commissioning, thereby blocking capacity that could otherwise be used by active projects.
Governance and conversion provisions
Recognising the evolving corporate structure of renewable energy developers, the CERC has clarified the treatment of parent-subsidiary relationships. Connectivity granted to a parent company can now be utilised by its subsidiaries and vice versa, and may also be transferred among subsidiaries of the same group. However, the regulation mandates that the promoters or shareholders of the connectivity grantee must retain control from the time of application until commissioning, preventing speculative transfers. Any change in control during this period requires prior approval from the nodal agency, which must publish detailed approval procedures after public consultation.
Conclusion
The amendment signifies a clear move towards a more transparent and data-driven transmission framework. For developers, it introduces flexibility through clear definitions of solar and non-solar access, streamlined withdrawals, and the option to expand capacity within existing connectivity, while enforcing discipline via stricter timelines, monitoring, and penalties for non-compliance. For system operators and CTUIL, it strengthens planning authority and also heightens oversight responsibilities through cluster-based coordination and transparent reporting. Overall, by aligning access rights with generation patterns, and enabling better utilisation of infrastructure, the amendment will enhance grid reliability and operational efficiency, preparing the interstate transmission network for smoother, more balanced renewable energy integration.
Aastha Sharma