Despite bountiful NE monsoon, hydel reservoir storage remains poor in TN
The steep fall in the hydel storage is due to less rainfall in the Nilgiris district which accounts for two-thirds of the state's total hydel storage.
CHENNAI: Despite the state witnessing floods owing to heavy rainfall this month, the storage in the hydel reservoirs (expressed in terms of million units) stood at 806 million units which is nearly 53 per cent less compared to last year's storage of 1,718 MU on the same date.
The steep fall in the hydel storage is due to less rainfall in the Nilgiris district which accounts for two-thirds of the state's total hydel storage.
As against the state's total hydel storage of 2439 MU, the Nilgiris Group comprising of Pykara and Kundah reservoirs alone have a combined storage of 1523 MU. However, the present storage in the Nilgiris stands at 317 MU which is only 20 per cent of its capacity. Last year, it stood at 1062 MU.
A senior Tangedco official attributed the less storage in the Nilgiris reservoirs to the average Southwest monsoon. Though the state has received 354 mm of rainfall during the SW monsoon as against its normal level of 328 mm, the Nilgiris has received only 772 mm of actual rainfall compared to the normal 842 mm.
In the Northeast Monsoon, Nilgiris has received 497 mm of rainfall as against its average of 491 mm.
After the onset of the Northeast Monsoon, the storage in the non-Nilgiris reservoirs like Periyar, Suriliyar, Kodayar, Papanasam and Servalar increased from 218 MU on October 1 to 434 MU on December 24.
According to Tangedco officials, the hydro generation from April 1 to December 24 period has come down by 37 per cent to 2,982 MU in 2023-24 from 4,769 MU in 2022-23.
"Due to less release of Cauvery water by the Karnataka, the hydro generation in the Mettur Dam, Mettur Tunnel and Lower Mettur Power House has fallen sharply with the less discharge of water for irrigation this year, " the official added. Last year, Mettur Dam and Mettur Tunnel Power House recorded the highest ever generation due to surplus release of water by Karnataka which in turn was let into sea, the official added.
Tangedco officials said that hydro stations were mainly used during the morning and evening peak hours as they offer the cheapest energy. "Due to less availability, we will be forced to procure power during the peak hours to meet hydro shortfall during the summer, " the official noted.