April 29 (Reuters) - Australia's Woodside Energy ( WDS )

announced on Monday it has approved a $17.5 billion

investment for the construction of a liquefied natural gas (LNG)

plant in Louisiana.

It is the first financial go-ahead to construct a LNG plant

in the U.S. since President Donald Trump returned to office

declaring an energy emergency and promising to unleash U.S.

energy onto the world.

The decision will help the U.S. further strengthen its

position as the world's largest exporter of the superchilled

gas.

The plant will cost $1.5 billion more than the original

price tag the company gave last year for the first phase of the

project and days after it said it was assessing the impact of

U.S. tariffs and other trade measures on the project.

The project's three separate processing units, or trains,

with a 16.5 million-ton-per-annum (Mtpa) capacity, are expected

to begin production in 2029. The project has the potential to

add two more LNG trains, taking its capacity to 27.6 Mtpa.

The investment will help Woodside deliver about 24 Mtpa from

its worldwide LNG portfolio in the next decade, contributing to

over 5% of global LNG supply, the company said.

The company also estimates the project will generate $2

billion in annual net operating cash in the 2030s, offering an

internal rate of return of 13% and a payback period of seven

years.

Stonepeak, an investor in the Louisiana LNG Infrastructure

LLC, will put $5.7 billion towards the expected capex, with most

of that money spent in the first two years of construction.

Woodside's share of the construction costs will be $11.8

billion, the company said.

Woodside's greenhouse gas emission reduction targets remain

unchanged after the final investment decision on the U.S.

project, the company said.