NEW DELHI, Nov 3 (Reuters) - India's power output fell at the fastest pace last month since the pandemic, as subdued industrial activity and unusually wet weather dented electricity demand and reduced cooling needs, a Reuters analysis of government data showed.

Total electricity generation in October fell 6% year-on-year to 142.45 billion kilowatt-hours (kWh), an analysis of data from federal grid regulator Grid-India showed.

"Continued rainfall in most parts of the country compared to last year led to lower demand," said Bhanu Patni, associate director, India Ratings and Research.

As most large festivals were in October, there was less industrial demand for power, said Debabrat Ghosh, head of India for Aurora Energy.

Growth in electricity use has tapered this year due to a broader economic slowdown and heavy rains, which have reduced cooling demand.

The country's coal-fired electricity generation in October also fell at the fastest pace since June 2020, when the COVID-19 pandemic led to a nationwide lockdown, as overall power demand declined.

Coal-fired generation, which typically accounts for about 75% of India's electricity output, has fallen in six out of 10 months this year, the most since 2020, Grid-India data showed.

India's coal-fired power generation fell by 13.2% in October on an annual basis to 98.38 billion kilowatt-hours (kWh), Grid-India data showed.

The decline in demand for fossil fuels for electricity generation in India, the second-largest importer of coal, has hurt giant miner Coal India.

Coal India, which accounts for about three-quarters of the country's production, suffered its worst profit decline in five years during the quarter ended September due to tepid demand for power this year.

The company's production declined about 10% in October, while coal supplied to power plants fell 6%.

Meanwhile, India's renewable energy output surged to 19.75 billion kWh in October, up 30.2% from a year earlier.