China's first shale gas field Fuling, with an annual capacity of 10 billion cubic meters, has become the world's second largest next to North America, Ecns.cn reported on Monday.

This marks the entry of China's shale gas development into a large-scale commercialization stage and is of great significance to the country's energy structure adjustment, relieving pressure on the supply of natural gas in central and eastern China, the report said, citing Dai Houliang, president of China Petrochemical Corporation (Sinopec Group).

It can also help to speed up energy savings and emission reduction as well as air pollution prevention and control, Dai said at a news conference Monday in Hong Kong when the company announced its 2017 annual results.

The Fuling shale gas field, developed by China's leading oil refiner Sinopec in the southwest municipality of Chongqing, has by now accumulatively produced and consumed over 16 billion cubic meters, generating over 6 billion cubic meters of shale gas in 2017. The maximum daily output of shale gas reached 16.7 million cubic meters, which can satisfy the daily demands of 33.4 million households, according to the report.

It is estimated that 3 billion cubic meters of shale gas can help reduce carbon dioxide emissions by 4.2 million tons, which is the equivalent of burning 6 million metric tons of coal.

China has made breakthroughs in shale gas exploration both in capacity and drilling techniques, and by 2020, proven reserves of shale gas are expected to surpass 1.5 trillion cubic meters, according to plans released by authorities in 2017.