India's hydroelectricity output decreased at the steepest pace in at least 38 years during the year that ended March 31, a Reuters analysis of government data showed as greater demand and unpredictable rainfall increased the country's reliance on coal-fired power.
The 16.3% drop in generation from the country's biggest clean energy source coincided with the share of renewables in power generation sliding for the first time since Prime Minister Narendra Modi committed to boost solar and wind capacity at the United Nations climate talks at Paris in 2015.
Renewables accounted for 11.7% of India's power output in the year that ended in March, down from 11.8% a year earlier, a Reuters analysis of daily load despatch data from the federal grid regulator Grid-India showed.
India is the world's third-largest greenhouse gas emitter, and the government often points to lower per-capita emissions compared to developed nations to defend rising coal use.
A five-year low in reservoir levels means hydro output will likely remain low during the hottest months of April-June, experts say, potentially boosting dependence on coal during a period of high demand before the monsoon starts in June.
K. J. Ramesh, former chief of the Indian Meteorological Department, said there is an increased chance of high rainfall during the annual monsoon this year. Still, any impact on hydropower output would not be visible before July.
"When hydro increases due to good rainfall, it should be used to reduce dependence on thermal," he said, adding that erratic rainfall means India should not count on hydro as a reliable power source in the future.
Declining share
Grid-India data showed that hydro's share in India's total power output fell to a record low of 8.3% during the fiscal year ended March 31, compared with an average of 12.3% in the 10 years through 2020.
The share of hydropower has steadily declined in recent years amid a slowdown in adding new capacity, with other sources, including coal, solar and wind, gaining share.
The lightest rainfall since 2018 meant reduced water levels in reservoirs, pushing annual hydro generation to a five-year low of 146 billion kilowatt-hours (kWh).
Meanwhile, power generation from coal and lignite in 2023/24 rose 13.9%, outpacing the 9.7% increase in renewable sources' output, data from the grid regulator showed. Total power generation rose 10.3% in 2023/24, Grid-India data showed.
India missed a 2022 target to install 175 gigawatts (GW) of renewable energy and remains 38.4 GW short of that goal. Grid-India data shows that India's dependence on fossil fuel for power hit a five-year high of 77.2% in 2023/24.
India's addition of renewables slowed to a five-year low in 2023.
According to energy think tank Ember, global hydropower output fell for only the fourth time since 2000 due to lower rainfall and warmer temperatures brought about by the El Nino weather pattern. Ember data showed that hydro output in India, the sixth-biggest hydropower producer, fell nearly seven times faster than the global average.