The Southern Regional Load Despatch Centre (SRLDC) has flagged the issue of the electricity transmission system in Tamil Nadu experiencing severe loading on Inter Connecting Transformers and intra-State transmission lines during the peak demand season every year, breaching the security of the grid. It has called for the augmentation of network capacity to handle future load growth.
“During the peak demand season, transmission lines in Chennai area, Neyveli area, Pugalur/Tiruchi area and Erode area are loaded severely,” it said in a recent communication to the Chairman and Managing Director of Tangedco, the State power utility.
There were 26 incidents of grid disturbance from April 2019 to March 2022. In 2021-22, there were six such incidents, resulting in a generation loss of 1,746 MW, the SRLDC said. These disturbances are primarily due to the fact that the transmission system up-gradation/commissioning has not kept pace with the growth of demand in Tamil Nadu.
The SRLDC said grid disturbances were near-miss events, in the sense that they had the potential to impact larger areas by means of cascade tripping. If such disturbances during the peak demand season in Tamil Nadu lead to cascade tripping, it would endanger even the national grid, it warned. Further, during the peak wind season, many intra-State transmission lines were severely loaded near Coimbatore, Tirunelveli and Kayatharu.
Citing the 19th Electric Power Survey, it said Tamil Nadu would experience a peak demand of over 27,000 MW in 2026-27, and would have to import about 18,000 MW from inter-State transmission systems. “With further power contracted to Tamil Nadu through long-term and medium term agreements, the violation in transmission would increase, and augmentation in the system is the need of the hour,” the SRLDC said.
Tamil Nadu saw an all-time high power demand of 17,563 MW on April 29, 2022. The Southern Regional Power Committee, under the Central Electricity Authority, held a special meeting on the transmission constraint in Tamil Nadu.
As per the notes of the meeting, even though Tamil Nadu is of the opinion that the demand may not exceed 26,000 MW in the time frame of 2026-27, as per the current trend, the State may draw 15,000-18,000 MW and, keeping this in view, intra-State network augmentation/straightening should be planned.
It was also emphasised that in future, cheaper power available in other regions should not be curtailed due to constraints in the intra-State transmission network.
