Chevron has started production of liquefied natural gas (LNG) and condensate at its $54bn Gorgon project on Barrow Island off the north-west coast of Western Australia.
The company expects to ship first cargo of LNG next week.
Chevron chairman and CEO John Watson said: "We expect legacy assets such as Gorgon will drive long-term growth and create shareholder value for decades to come.
"The long-term fundamentals for LNG are attractive, particularly in the Asia-Pacific region, and this is a significant milestone for all involved."
Gas for the Chevron-operated project comes from the Gorgon and Jansz-Io gas fields located between 130km and 220km off the north-west coast of Western Australia.
The project includes a 15.6Mtpa LNG plant on Barrow Island, a carbon dioxide injection project, as well as a domestic gas plant with the capacity to supply 300 terajoules of gas per day to Western Australia.
It will have three production trains with the capacity to produce 15.6 million tonnes of LNG per annum.
The Gorgon project is a joint venture between the Australian subsidiaries of Chevron (47.3%), ExxonMobil (25%), Shell (25%), Osaka Gas (1.25%), Tokyo Gas (1%) and Chubu Electric Power (0.417%).
More than 80% of the company's Australian subsidiaries' equity LNG from the Gorgon and Wheatstone projects is covered by sales and purchase agreements.
Image: The Gorgon project gets gas from the Gorgon and Jansz-Io gas fields. Photo: courtesy of Chevron Corporation.