China's benchmark power coal price edged up on Wednesday, marking a rise for the sixth straight week, as increased summer power use drove up demand for coal.

The Bohai-Rim Steam-Coal Price Index, a gauge of coal prices in northern China's major ports published weekly, grew 0.17 percent from a week ago to 582 yuan (more than 85 U.S. dollars) per tonne, according to Qinhuangdao Ocean Shipping Coal Trading Market Co. Ltd.

The coal price has been on a periodic upward trajectory since mid-June as lingering heat waves boosted coal consumption in thermal power plants, and reduced production capacity to some extent led to the shortage in supply.

But analysts dismissed the possibility of continued, sharp price hikes as Wednesday's mild rise signaled the trend has become more stable.

The government has moved in to stabilize prices, and coal producers have also reassured the market with promises of long-term stable supply.

The coal price was 38 percent higher than a year ago, partly due to the country's capacity cuts in the glutted coal and steel sectors, among others.

China aims to phase out 150 million tonnes of coal capacity this year. As of the end of May, around 97 million tonnes of coal capacity had been cut, accounting for 65 percent of the annual goal.