China's largest offshore gas field produces 4.5-mln-tonnes oil equivalent in 2025

An aerial drone photo taken in April, 2025 shows the Deep Sea No. 1 energy station, in south China's island province of Hainan. (CNOOC/Handout via Xinhua)

HAIKOU, Jan. 2 (Xinhua) -- China's largest offshore gas field, named Deep Sea No. 1, has recently completed its 100th shipment of crude oil since being put into production, announced the China National Offshore Oil Corporation (CNOOC) on Friday.

The field's total oil and gas output in 2025 exceeded 4.5 million tonnes of oil equivalent, comparable to that of a medium-sized onshore oilfield.

The project was implemented in two phases, with production commencing in 2021 and 2025, respectively.

The second phase of the project represents the country's most challenging deepwater gas development to date, as it operates at the highest temperatures and pressures ever encountered in domestic offshore exploration. Additionally, it is China's deepest gas development, functioning at water depths exceeding 1,500 meters.

The Deep Sea No. 1 gas field now boasts a daily output of 15 million cubic meters of natural gas and over 1,600 tonnes of condensate oil.