The National Energy Administration vowed to ensure sufficient energy supply during the heating season this year by intensifying efforts to increase coal output this winter and next spring, which it said will witness more coal demand compared with the current level.

The administration will keep a close look at domestic coal production while ensuring stable coal supplies and prices this heating season, it said during a release on Monday.

According to the administration, coal mines in Shanxi, Shaanxi and the Inner Mongolia autonomous region witness daily coal production of more than 8.3 million tons, contributing 75 percent of the country's total coal output.

Recent daily coal output has reached 11.93 million metric tons, the highest in recent years. Average daily coal production reached 11.66 million tons from Nov 1 to 5, up over 1.2 million tons from the end of September.