Surging market demand as winter sets in is pushing up coal prices in China.

The price per ton in Shanxi, China's top coal producing province, was up 40 yuan (about 5 U.S. dollars) on the end of October, and the price of high-quality coal rose even more.

Experts said heavier demand -- due to greater dependence on coal by power plants and people stockpiling coal for the winter -- was fueling the higher prices.

Another factor was the government's determination to shut down small coal mines in response to their appalling work safety record.

Rising production costs -- such as the compulsory allowance to miners and coal resource utility fees -- were another cause of price hikes.

Preliminary statistics show each miner was paid on average 10 yuan extra for each ton of coal since the Ministry of Labor and Security urged mine producers to do so in July.

The pilot coal resource utility fee will go into full swing next year, adding another 70-80 yuan to the per-ton production cost.

China is the world's No. 1 coal producer and consumer. Last year, its coal output reached 2.19 billion tons and the figure is expected to climb to 2.45 billion tons this year.