The announcement came after first cargo was loaded on to the Methane Rita Andrea on December 28.

The second cargo of LNG from the facility will be loaded on to the Methane Mickie Harper which is expected in Gladstone in the first week of January.

QCLNG is the world's first LNG project to be supplied by coal seam gas. The start of production from the plant's first LNG train is the result of more than four years of development and construction on Curtis Island.

At plateau production, expected during 2016, QCLNG will have an output of about 8 million tonnes of LNG a year, connecting over 2000 onshore wells spread across 4500 square kilometres which flow through a 540km pipeline to the Curtis Island liquefaction facility near Gladstone. Following this it is chilled to -162C, changing its state to a liquid form, making it 600 times smaller and enabling it to be stored and transported in LNG vessels to markets.

BG Group's natural gas also supplies power stations, industrial users and gas retailers in Australia under long term contracts.

Water produced from gas wells will be processed at two treatment plants providing supplies for use by local landholders, industry and communities.

BG Group interim executive chairman Andrew Gould called the first cargo an “immense achievement” in delivering a “highly complex” LNG project.

“The start-up of QCLNG is testament to the hard work, skill and dedication of all our employees, partners and customers including the thousands of individuals who have been involved in physically building the plant,” he said.

“The ongoing support from both the State Government of Queensland and the local councils of our upstream region and in Gladstone has also been pivotal in this development.

“We thank them all.”