China has discovered an 89.2-billion-tonne coal reserve at Sha'er Lake in northwest Xinjiang Uygur autonomous region, which experts say is the largest of its kind in Asia.

"We have submitted an exploitation plan for the super-large coal field to the central authorities. Once approved, the exploitation will officially begin," Wei Cheng, deputy director of the Sha'er coal field excavation headquarters, said Thursday.

Prospecting experts have spent a year calculating the coal field's reserves, Wei said.

"The coal's quality is fine, with low sulphur, low phosphorus, low ash, high caloricity and relatively fewer harmful elements," he said.

Reports estimate there are coal reserves of over 2 trillion tonnes in Xinjiang, or about 40 percent of China's total coal reserves.