Unbridled solar power injection into grid will have financial implications, KSEB tells public hearing

The Hindu

11-07-2025

The cost of managing unbridled injection of solar power to the grid by prosumers in Kerala comes to around ₹500 crore a year, with a per-unit impact of 19 paise on electricity consumers, according to the Kerala State Electricity Board (KSEB).
The KSEB presented this assessment while giving its views at a public hearing organised by the Kerala State Electricity Regulatory Commission on the draft renewable energy regulations. At this pace, the per-unit impact on consumers could shoot up to 40 paise per unit by 2034-35, the KSEB told the hearing.
With day-time solar power injection to the grid crossing 1,000 MW, the KSEB says it is finding it tougher by the day to absorb this huge volume. The power utility says it conducted a study which showed that prosumers in general were exporting 75.53% of their generation during solar hours. In the case of domestic prosumers alone, this was as high as 79.21%.
The cost for accommodating this volume, based on 2024-25 figures, is pegged at ₹500 crore a year.
This cost, according to KSEB officials, arises from multiple components; the loss incurred for having to surrender power from long-term contracts for accommodating the renewable energy injection, the loss incurred by the KSEB from having to replace power 'banked' with it by prosumers during the daytime with high-cost power during peak evening hours and the spending on infrastructure needed to manage the solar power fed into the system.
The KSEB has welcomed the draft KSERC (Renewable Energy and Related Matters) Regulations, 2025 but suggested a number of modifications. On the contentious issue of Net Metering Systems (NMS), the KSEB wanted NMS to be limited to 2 kilowatt (kW). All new systems above 2 kW should be brought under Net Billing System (NBS), according to it.
The KSEB suggestions came at a time when the commission's draft proposal that the maximum capacity for new Net Metering connections should be set at 3 kW had drawn flak from prosumers.
The KSEB also welcomed the commission's proposal to introduce grid support charges, another provision that had drawn considerable criticism during the hearings. The KSEB wanted the grid support charges to be applicable 'uniformly to all existing prosumers, including domestic consumers, with solar capacity up to 10 kW.'
According to the KSEB, the grid support charge recommended by the commission (₹1 per unit of renewable energy exported to the grid) was too low as the actual cost of load balancing, wheeling, and banking would come to ₹7 per unit. But the KSEB said it was accepting the commission's proposal, given the need to avoid burdening consumers.
The KSEB also wanted the commission to set separate Average Power Purchase Cost (APPC) for solar power and wind power, on the grounds that they be 'source-specific to reflect actual costs.' The KSEB suggested that the solar APPC be fixed at ₹2.81 per unit and wind APPC at ₹3.17 per unit.