Weak monsoon halves TN hydel power output, forcing costly electricity purchases
Chennai, July 20
A weak southwest monsoon, poor inflows into major reservoirs and prolonged heatwave conditions have sharply reduced hydel power generation in Tamil Nadu this year, increasing the state's dependence on expensive electricity purchases from the power exchange to meet rising demand.
Official data shows that between April 1 and July 17, Tamil Nadu generated only 751.034 million units (MU) of hydel power, nearly half the 1,509.549 MU produced during the corresponding period last year.
The steep fall has come at a time when electricity demand remained high well into July, placing additional pressure on the state's power system.
Hydel power is among the cheapest sources of electricity available to the state, with generation costs remaining below Rs 1 per unit.
Tamil Nadu generally maximises hydel generation during the summer months and peak-demand periods to reduce dependence on costlier power sources. However, this year, the extended spell of high temperatures combined with below-normal rainfall significantly reduced water availability in reservoirs, limiting the operation of hydroelectric stations.
The fall in hydel generation has also resulted in a substantial financial burden on the state's power distribution utility. To bridge the shortfall, the utility has been compelled to procure electricity from the power exchange over the past three months at prices ranging between Rs 16 and Rs 20 per unit.
Officials estimate that nearly 2,000 MU of electricity has been purchased during this period, considerably increasing overall power procurement costs.
The situation has been aggravated by inadequate releases of Cauvery water from Karnataka, which further reduced water availability in reservoirs feeding several hydroelectric projects.
With monsoon activity yet to improve significantly, officials expect hydel generation to remain under pressure in the coming weeks unless rainfall increases substantially across the catchment areas.
Experts within the power sector have also pointed to the impact of inadequate reservoir maintenance on hydel generation.
While desilting was carried out in a few reservoirs, including Bhavanisagar and Kundah, in 2010, no major desilting work has been undertaken since then. Officials estimate that silt accumulation has reduced the effective storage capacity of most reservoirs by nearly 20 per cent, limiting their ability to store water during the monsoon and affecting electricity generation.
They believe timely desilting could have improved storage capacity, enhanced hydel output and reduced the state's dependence on costly power purchases during periods of high demand.
— IANS
Reader Comments
As a Chennai resident, I feel this directly. Our electricity bills have gone up, and we keep hearing about power cuts during peak hours. The Cauvery issue with Karnataka is not helping either. We need better water sharing agreements and maybe more pumped storage projects to balance this. Desilting should be done every few years, not once in a decade! 😤
It's frustrating to see the same mistakes repeated every year. Tamil Nadu has plenty of coastline—why not invest in offshore wind or tidal energy? The state also has the solar potential, especially in southern districts. Instead, we keep buying expensive power from exchanges because of poor planning. The desilting issue highlights how maintenance is ignored until crisis hits. 🤷♂️
I agree that desilting should have been done regularly, but let's not forget that the southwest monsoon has been weakening overall due to climate change. The real solution is to diversify our energy mix—more solar rooftops, more wind farms, and smarter grid management. And yes, better coordination with Karnataka on Cauvery releases is long overdue. 😒
The financial burden on TNEB is enormous. Purchasing 2,000 MU at Rs 16-20 per unit is like burning money. This could have been avoided with proper reservoir maintenance and maybe some advance forecasting. The government should also consider micro-hydel projects in smaller streams to supplement. Every drop should count! 💧⚡
Weak monsoon is one thing, but inadequate release of C
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