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The Tripura State Electricity Corporation Limited (TSECL) has warned that stage-wise automatic load shedding may become necessary in predefined areas of the state for limited periods to protect grid stability amid tightening power availability and rising electricity demand.
The corporation said on Friday that the measure may be required during evening and night peak hours to prevent a decline in grid frequency and safeguard the interconnected power system. In an assessment, TSECL Managing Director Biswajit Basu and Director (Technical) Subir Sen said Tripura's peak electricity demand, including cross-border power exports, had reached approximately 540 MW. The state is currently procuring around 50-60 MW through power exchanges to bridge the supply gap during evening peak hours after sunset. Tripura meets its electricity demand through a combination of gas-based power generation within the state, allocations from central-sector generating stations, including coal, gas and hydropower plants, bilateral power purchase agreements and electricity procured through power exchanges. The officials said India's growing electricity demand, coupled with constraints in power availability, had increased the challenge of maintaining a balance between generation and consumption, particularly after sunset when solar power generation declines while demand remains high. Although India has significantly expanded its solar and wind energy capacity, coal continues to account for nearly 70 per cent of the country's electricity generation, leaving the sector vulnerable to fuel transportation disruptions, weather conditions and maintenance-related outages at generating stations. Reduced hydropower generation following weak rainfall, higher temperatures driving air-conditioning demand and maintenance at several coal-fired power plants have further tightened electricity supplies, according to the assessment. Data from the Grid Controller of India showed that the national electricity grid experienced an average power shortfall of nearly 4 GW per day during the first 10 days of October 2026. Several states have sought additional power allocations from the Centre to avoid supply disruptions, while limited availability in the electricity market has increased the cost of short-term power procurement. The officials also pointed to the widening gap between demand and supply in electricity markets. On October 6, demand in the Day-Ahead Market was nearly five times the electricity offered for sale, while demand in the Real-Time Market exceeded available sell offers by more than eight times. Explaining the need for protective measures, the officials said India's interconnected electricity grid operates at a nominal frequency of 50 Hz, and an imbalance between generation and consumption in any part of the system can affect grid frequency across the country. They said that even if Tripura has sufficient electricity to meet its own demand, shortages elsewhere could contribute to a decline in the overall grid frequency. A sustained fall in frequency, coupled with excessive power withdrawal, could threaten grid stability and increase the risk of generating units tripping or a wider system disturbance. To prevent such situations, Under Frequency Relays (UFRs) are deployed across transmission and distribution networks. These automatic protection devices initiate Under Frequency Load Shedding (UFLS), disconnecting predetermined blocks of load when grid frequency falls below specified safety thresholds. The mechanism rapidly reduces electricity demand to help restore the balance between generation and consumption and prevent a potential cascading blackout. Essential services, including hospitals, drinking water supply installations, railway traction and defence facilities, are kept off the designated UFR feeder lists. Under the Indian Electricity Grid Code, 2023, a standardised four-stage UFR scheme has been prescribed to arrest declining grid frequency. The prescribed settings are 49.4 Hz for Stage 1, providing relief equivalent to 5 per cent of peak demand; 49.2 Hz for Stage 2, providing 6 per cent; 49.0 Hz for Stage 3, providing 7 per cent; and 48.8 Hz for Stage 4, providing 7 per cent. Together, the four stages are designed to provide demand relief equivalent to approximately 25 per cent of the previous year's peak demand. As part of efforts to strengthen grid safety in the Northeast, the North Eastern Regional Power Committee (NERPC) has directed the installation of 21 Under Frequency Relays at the 33 kV level of Tripura's power system. According to TSECL, grid frequency has approached the first-stage UFLS threshold on several occasions this month, with readings falling as low as 49.42 Hz during peak periods, just above the Stage 1 setting of 49.4 Hz. The corporation said it was making efforts to maintain a balance between electricity demand and supply. However, shortages in overall power availability, including limited supplies in the electricity market during certain 15-minute time blocks in the evening and night, could necessitate stage-wise automatic load shedding in predefined areas for limited periods. The officials emphasised that such measures would be intended to safeguard the larger interconnected power grid and would not necessarily indicate an inability to meet Tripura's electricity requirements under normal conditions. They expressed optimism that the situation would improve as winter sets in by November, with lower temperatures expected to reduce electricity demand and help restore the demand-supply balance. If grid frequency remains within permissible limits, UFLS action may not be required. The officials said the objective was to ensure electricity was delivered safely, reliably and economically to consumers in Tripura while maintaining the stability and security of the national electricity grid. (ANI)
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