Aerial photo taken on July 9, 2019 shows China Railway Taiyuan Group Co., Ltd. inspectors patrolling on the Datong section of the Daqin Railway in Datong, north China's Shanxi Province. (Xinhua/Cao Yang)

An average of 20 freight trains fully loaded with coal arrive in southwest China's Chongqing Municipality every day from Shaanxi and Shanxi provinces, major coal production bases, as well as Xinjiang Uygur Autonomous Region to help fuel coal-fired power plants in the megacity.

Due to a slew of overlapping factors such as rapid economic recovery, swift foreign trade and rising coal price, west China's economic hub of Chongqing has faced power supply pressure since the third quarter.

From January to October, Chongqing's total electricity consumption increased by 14.9 percent year on year. In October alone, coal-fired power consumption soared by more than 300 percent year on year.

According to the Chongqing economic and information committee, Chongqing's thermal power accounts for over 60 percent of its installed power capacity, while all coal needs to be diverted from outside the city.

Since the beginning of this year, Shaanxi Province has supplied 8.8 million tonnes of coal to Chongqing, an increase of 84 percent year on year. Chongqing has also stepped up the purchase of coal from Shanxi and Xinjiang, which are expected to deliver a total of 4 million tonnes of coal to Chongqing this winter and next spring. The supplemental purchase can guarantee Chongqing's power supply.

Coal trains are also gathering at Hudong Station in China's first coal transportation railway line linking the coal production city of Datong in Shanxi with Qinhuangdao Port in Hebei Province, from where coal can be transferred to the country's southern and eastern regions for power supply and heating.

Datong-Qinhuangdao Railway, deemed China's energy transport artery, is an electrified railway designed exclusively for transporting coal from the provinces of Shanxi and Shaanxi and the Inner Mongolia Autonomous Region to the energy ports of Qinhuangdao and Caofeidian.

China Railway Taiyuan Group Co., Ltd. has increased its daily train trips to 94 from 85, with the departure interval shortened to every 13 minutes on the railway, said Ren Xin, deputy director with the company's dispatching office, adding that the trains carry 1.3 million tonnes of coal per day.

The coal output in Shanxi is expected to exceed 1.2 billion tonnes this year and the power transmission from the province will exceed 9 million kilowatts in December. The output of coal-bed methane will reach 4.2 billion cubic meters this winter and next spring, forecast local authorities.

In the first seven days of November, Shanxi's average daily coal output reached over 3.5 million tonnes, an increase of 170,000 tonnes compared with that in October, showed data from the energy bureau of Shanxi.

As of Nov. 9, Shanxi has supplied 15.19 million tonnes of coal to 14 provinces, regions and municipalities including Shanghai, Zhejiang and Jilin.