A renewable energy generating station (REGS) operating with or without an energy storage system (ESS) can now become an entity with solar hour access for a longer length of time, according to the Central Electricity Regulatory Authority (CERC).
Solar Hour Access Rules
This expansion also applies to renewable hybrid generating stations (RHGS) that combine solar electricity with another source, with or without ESS, and renewable power park developers (RPPD) based on solar sources.
The third revision of CERC’s Connectivity and General Network Access to the inter-State Transmission System Regulations, 2022 established the idea of solar hour access and non-solar hour access. In a suo motu ruling, the regulator addressed the bottlenecks in specific clauses.
The third amendment to the GNA, which went into effect on September 9, 2025, intends to optimize grid utilization by minimizing insufficiencies and permitting numerous projects to use the same transmission capacity. Time-block-based limited access is used to achieve this.
Solar vs Non-Solar Access
Here, transmission access is separated into two categories: non-solar hour access, which uses wind power and ESS at night, and solar hour access, which uses solar or hybrid electricity during the day.
According to the third amendment, a REGS, RPPD, or RHGS with specific power source combinations combined with an in-principle or final grant of transmission connectivity, or where GNA is effective, may be converted into an entity with solar hour access within one week of the third amendment’s three-month expiration date.
Within three months of the Third Amendment’s implementation, such entities may request for an extra capacity under specific GNA laws. The Nodal Agency will take this application into consideration while converting the entity to one with sun hour access.
Developers Seek Deadline Extension
The CERC, in its order, noted that renewable energy developers and their associations had sought a three-month extension of the deadline for converting REGS (with or without energy storage systems) or RPPD based on solar power, or RHGS using solar in combination with another source (with or without storage), into entities eligible for solar-hour access after the Third Amendment comes into force.
Developers emphasized that, in accordance with several GNA laws, they need extra time to make decisions and get their firms’ consent before investing in more generation capacity.
Solar Hour Transition Timeline
Additionally, one of the inventors said that there is presently about 300 gigawatts (GW) of solar ISTS connection. However, the ESS technological environment, specialized labor, and supply chain are not presently scalable to enable the execution of huge quantities in short amounts of time. Realistic planning requires more time.
According to CERC, the three-month timeframe was suggested in the April 2025 draft amendment. It believes that organizations have “sufficient” time to prepare for applications. However, a two-and-a-half-month (75-day) extension starting on December 9, 2025, is permitted as a one-time measure, given the recent introduction of the idea of sun hour access.
As a result, it stated, “we loosen Regulation 5.11(b) of the GNA Regulations and grant five and a half months from the date of effectiveness of Third modification (September 9, 2025) in place of three months under Regulation 5.11(b) of the GNA Regulations.”
