China has huge potential for natural gas usage in the transportation sector as an increasing number of clean energy vehicles take to the road, an industry specialist said.

The number of vehicles using natural gas is predicted to reach 2.1 million in 2015 in China and hit 3.2 million in 2020, said Dai Jiaquan, deputy director of the Oil Market Research Office with the CNPC Economics and Technology Research Institute on Thursday.

This will lead to soaring natural gas consumption in the following years, said Dai during the China-Japan Joint Symposium on Asia Oil and Gas held in Beijing.

He estimated that China's natural gas use in the transportation sector will be 32 billion cubic meters in 2015 and reach 56 billion cubic meters in 2020.

This means it will replace 26 million metric tons of petroleum in 2015 and 46 million tons in 2020.

Between 2000 and 2012, China's natural gas consumption grew from 900 million cubic meters to 16.6 billion cubic meters.

The transportation sector accounted for 4 percent of total natural gas consumption in 2000. The figure grew to 11 percent in 2012.