CHENNAI: With the southwest monsoon remaining weak and water in key reservoirs low, Tamil Nadu has witnessed a 50% decline in hydel power generation this year, forcing the state power utility to rely on costly power purchases from the electricity exchange. Between April 1 and July 17 of this year, the state generated only 751.034 million units (MU) of hydel power, compared to 1,509.549 MU during the corresponding period last year.
A senior official from the Tamil Nadu Green Energy Corporation Limited (TNGECL) told TNIE, “Hydel power is one of the cheapest sources of electricity, with the generation cost below Rs 1 per unit. We typically utilise hydel stations extensively during summer and peak demand hours. Last summer, we were able to generate a reasonable quantity of hydel power and manage the demand. However, this year, the prolonged heatwave conditions continued into July, while poor rainfall reduced reservoir inflows.”
The sharp decline in hydel generation also increased the financial burden on the state’s power distribution utility. According to the official, the discom was forced to purchase electricity from the power exchange at rates ranging between Rs 16 and Rs 20 per unit over the last three months.
The official said, “The utility is estimated to have procured nearly 2,000 MU from the power exchange during this period, resulting in significantly higher power purchase costs,” adding that the poor release of Cauvery water from Karnataka exacerbated the problem.
With monsoon activity yet to improve, officials expect hydel power generation to remain under pressure in the coming weeks.
Another senior official said that the last major desilting work was carried out in 2010 in a few reservoirs, including Bhavanisagar and Kundah. The official said, “No desilting work has been undertaken after that. At present, nearly 20% of the capacity in most reservoirs is lost to silt accumulation.” The official said that timely desilting could have increased the effective storage capacity and helped generate additional hydel power. “However, the opportunity has been missed,” he added.