Since the China (Zhejiang) Pilot Free Trade Zone started in 2017, the annual supply of bonded bunker fuel oil in Zhoushan has surged from 1.06 million metric tons to 7.04 million tons in 2023, making Zhoushan China's largest and the world's fourth-largest bunkering port.

Last year, the export volume of Zhoushan's bonded bunker fuel oil reached 48 billion yuan ($6.63 billion), accounting for over 40 percent of the city's total foreign trade exports. The total maritime service output value in Zhoushan was 51.9 billion yuan.

The low-sulfur fuel oil export tax rebate policy has been implemented in Zhoushan since the establishment of the Zhejiang Pilot FTZ. Refineries can produce low-sulfur fuel oil and receive export tax rebates. As a result, Zhoushan's low-sulfur fuel oil prices are on par with, or sometimes even lower than, those of top international ports.

Zhoushan Customs has introduced a policy for blending high- and low-sulfur bonded bunker fuel oil in the FTZ. "For customers, this reduces the cost of bonded oil by about $5 to $8 per ton," said Shen Jianbin, general manager of Zhejiang Free Trade Zone PetroChina Fuel Oil Co.

There are now 20 licensed fuel supply companies in Zhoushan, creating a freer market with diverse options ranging from state-owned, private, and foreign-invested companies.

Collaboration among customs, maritime, and border inspection departments has improved the efficiency of bonded oil clearance, allowing a single fuel supply ship to refuel multiple vessels in one voyage.