China’s first independently-developed ultra-deepwater gas field Shenhai Yihao, or Deep Sea No. 1, has commenced the construction of its phase II project, the China National Offshore Oil Corporation (CNOOC) said Friday. The phase II project, located 200 km offshore from Sanya, south China’s Hainan Province, is expected to increase the natural gas reserves of Shenhai Yihao from 100 billion cubic meters to 150 billion cubic meters once it is completed, according to the CNOOC. Aiming to drill 12 wells, it will also expand the peak annual output of the gas field to 4.5 billion cubic meters, equivalent to 90 percent of Hainan’s natural gas consumption in 2021, the company said. Liu Shujie, the chief engineer with the CNOOC’s Hainan branch, said the phase II project would progress under more complicated seabed geological conditions, overcoming water depth, high temperature, and high pressure. The total depth of drilling will surpass 60,000 meters, 220 percent more than phase I and unparalleled in a global comparison, Liu said. Put into operation in June 2021, the Shenhai Yihao ultra-deepwater gas field is the deepest of its kind in China.