Unseasonal rains may boost hydro power supply

Unseasonal rains in March have lifted reservoir levels, easing temperatures and boosting hydropower supply, offering some respite from the impending summer heat, even as the wet weather destroyed winter crops in their wake.

Hydropower usually comes into play in June as rains begin; however, as of 31 March, live storage at 146 reservoirs monitored by the Central Water Commission (CWC) was 76.058 billion cubic meters (BCM), which is 94% of the storage a year ago, and 118% of the average of last 10 years. Of these 146 reservoirs, 18 are hydropower projects with a total live storage capacity of 34.960 BCM.

The rise in reservoir levels will support more production and ease power demand as the temperature rises in the days ahead, analysts said. Hydropower constitutes around 11.4% of India’s total installed power capacity. As of 28 February, installed hydropower capacity in the country stood at 46.85GW.

The Pong Dam on the Beas River in Himachal Pradesh, with a capacity of 396MW as of 31 March was 34% of the total capacity, against 29% last year and the 10-year average of 24%. The 800MW Kol Dam in Himachal Pradesh had a storage level of 79% of the live capacity. Although it is lower than last year’s 91%, it is way above the 10-year average of 58%.

Similarly, the 80MW Panchet Hill project in Jharkhand had a storage of 93%, against 100% a year ago and the 10-year average of 68%.

In Maharashtra, the state with the highest number of large dams, the 300MW Mulshi dam had a storage level of 42% against 28% a year ago. The Koyna dam, with a capacity of 1,920MW, had a storage level of 57% of the capacity, compared to 60% during the same period last year and the 10-year average of 50% of the capacity. Vikram V., vice president and sector head of corporate ratings, ICRA, said: “Although most of the hydropower projects in the north and northeastern parts of the country are dependent on the riverine ecosystem, several hydro projects in the west and south may have been supported by the recent rains.”

The rains also eased power demand. In the first two weeks of March, the peak power demand met was around 205GW, which has now fallen below 190GW. According to the latest data from the Grid Controller of India, the maximum peak power demand met during the day was 187.73GW.

Peak power demand this year is expected to reach 229GW, against 211GW recorded last year. The government has taken several steps to ensure adequate power supply during the summers, including directing all hydropower producers to operate hydropower plants optimally at peak hours in April and May.