On June 25, 2025, China National Offshore Oil Corporation (CNOOC) confirmed the successful launch of Phase 2 of its ultra‑deepwater gas project—Shenhai Yihao (Deep Sea No. 1)—in the South China Sea With this expansion, China immediately gains an additional 4.5 billion cubic meters (BCM) of annual gas supply, solidifying its status in China energy infrastructure.
Proven geological reserves exceed 150 BCM
Water depths reach 1,500 m+, with well depths more than 5,000 m. This makes it China’s deepest offshore gas development
Phase 2 incorporates 12 subsea gas wells, a jacket platform, subsea production system, five undersea pipelines, and five umbilical cables, covering over 170 km
Operates under record-breaking temperatures (138°C) and pressures (69 MPa)—almost 1,000× household pressure
Utilizes an innovative integration of subsea systems, shallow-water platform, deepwater semi-submersible platform, and remote operations
Gas is transported via pipelines to coastal terminals in Hong Kong, Sanya (Hainan), and Zhuhai (Guangdong)
Feeds into the Guangdong–Hong Kong–Macao Greater Bay Area and is integrated with the national gas pipeline network, strengthening China energy security
Adding 4.5 BCM annually reduces reliance on LNG imports, increases natural gas production, and aligns with Beijing’s push for cleaner energy shifts from coal to gas.
The Shenhai Yihao project exemplifies China’s ability in deep‑sea drilling technology and complex offshore gas extraction. Techniques and learnings are pivotal for future developments, including the Baodao 21‑1 field near Hainan
Increased domestic output may lower China’s LNG imports, influencing global LNG spot prices and demand trends—benefitting European and Asian markets.
Ensuring supply to strategic economic zones like Hong Kong, Guangdong, and Hainan underscores China’s regional energy dominance, especially in contested maritime zones.
Building on Phase 2’s success, CNOOC aims to explore similar ultra-deepwater reservoirs using perfected tech. Expect more strategic investments in subsea remote platforms and integrated networks to bolster China energy infrastructure.