China's benchmark power coal price rose by 1 yuan (15 U.S. cents) per tonne during the past week.

The Bohai-Rim Steam-Coal Price Index (BSPI), a gauge of coal prices in northern China's major ports, stood at 579 yuan per tonne Wednesday, according to Qinhuangdao Ocean Shipping Coal Trading Market Co. Ltd.

Analysts said the supply and demand balance was broken after four flat weeks. Falling storage in electric power plants was one of the factors affecting the price.

Meanwhile, the railway line connecting the coal city of Datong, Shanxi Province, and the port city of Qinhuangdao, Hebei Province, has been under maintenance since April 7, which affected coal supply and boosted market confidence. A malfunction in the power system of the city of Zhangjiakou also affected supply.

Rising coal futures in the past week have also impacted the coal price.

Released by the Qinhuangdao Ocean Shipping Coal Trading Market Co. Ltd every Wednesday, the BSPI is considered a leading indicator of China's coal prices.