(Reuters) - U.S. liquefied natural gas (LNG) company Venture Global LNG sought authorization on Thursday from U.S. energy regulators by Aug. 30 to unload the first LNG commissioning cargo at the Plaquemines export plant under construction in Louisiana.

About a week ago, a tanker full of LNG named the Qogir docked at Plaquemines, according to Venture Global and data from financial firm LSEG. The tanker came from Norway.

Energy analysts and traders said Venture Global would use that LNG to cool down parts of the Plaquemines facility as part of the plant's testing and commissioning process.

Officials from the company were not immediately available for comment. Earlier in the week, Venture Global said the Qogir docked at Plaquemines but did not provide other information.

On Thursday, Venture Global filed with the U.S. Federal Energy Regulatory Commission (FERC) for authorization no later than Aug. 30 to unload the first LNG commissioning cargo on or after Aug. 30.

LNG plants under construction, like Plaquemines, use super-cooled fuel to test and cool equipment in preparation for startup.

In addition to the Qogir, another LNG vessel, the Venture Gator, which was not fully loaded with LNG, according to data from LSEG, was anchored in the Mississippi River near Plaquemines. Analysts said it was likely the vessel, which was listed as available for orders, would go to Plaquemines.

Plaquemines started pulling in small amounts of natural gas from U.S. pipelines in late June, analysts have said the plant could start turning gas into small amounts of LNG in test mode in coming months.

Venture Global has said that building the two phases at Plaquemines would entail an investment of about $21 billion.

Analysts have said they expect Venture Global to complete work on the first 1.8-billion cubic feet per day (bcfd) phase of Plaquemines from 2024 to 2026 and the second 1.2-bcfd phase from 2025 to 2026.

The U.S. is already the world's biggest LNG exporter with seven export plants able to turn about 13.8 bcfd of gas into about 104.6 million tonnes a year (MTPA) of LNG.

One billion cubic feet is enough gas to supply about five million U.S. homes for a day.