Electricity generation at Indian utilities rose 4% to 66.88 gigawatt hour in December from a year earlier, but missed the targeted 70.36 GWh, government data showed Monday.

Generation at thermal stations--including coal, lignite, gas and diesel--rose 2% to 57.33 GWh last month, slower than the government's estimate of 60.89 GWh, data on the Central Electricity Authority website showed.

The coal-based power plants, which account for four-fifth of thermal generation, operated at 76.92% capacity in December compared with 80.16% a year earlier. The plants operated at lower capacities because
India imported less coal than expected, CEA said.

Indian utilities imported 16.19 million metric tons of coal in April-December, making up little less than half of the target to import 35 million tons in the year through March. Power producers need to import coal as domestic output falls short of demand.

Output at hydro-power plants rose 8% to 6.97 GWh, falling 3% short of the government's target.

Power generation at nuclear plants rose 64% to 2.4GWh, exceeding the government's target of 2.02GWh. CEA didn't give any reason for the higher generation at these plants.