MELBOURNE—Royal Dutch Shell on June 10 shipped the long-awaited first cargo of LNG from its Prelude floating LNG plant off northwest Australia, sealing Australia's position as the world's top LNG exporter.

Prelude's start-up marks the end of a $200 billion LNG construction boom in Australia over the past decade, during which eight LNG plants were built on the country's eastern and northwestern coasts.

Prelude's first cargo had been targeted for 2018, but has been delayed as the company tackled a string of teething problems at the world's biggest floating vessel, a 490-m long (1,600 ft) ship.

"Today's first shipment of LNG departed from Prelude FLNG, safely," Shell's integrated gas and new energies director, Maarten Wetselaar, said in a statement.

The shipment on the Valencia Knutsen LNG tanker is going to customers in Asia, Shell said.

Prelude will produce 3.6 mtpa of LNG. The start-up comes just as spot LNG prices have sunk to more than three-year lows, as new projects in Australia and the U.S. have boosted global supply over the past year, while demand in Asia was dented by a mild winter.

"How fast Prelude delivers its second and third cargo, and ramps up to plateau output will be a key indicator of success. Shell will be keen to ramp up to full production quickly to counteract any reserves impact from the already producing and connected Ichthys field," said Wood Mackenzie's senior analyst Daniel Toleman in a statement.

"With Prelude onstream, Australia is on track to export more than 80 MMtpa of LNG, which surpasses Qatar as the largest LNG producer in the world," he added. "The completion of Prelude marks the end of the Australian greenfield LNG boom. The next investment cycle is already in sight, with backfill projects – Scarborough, Barossa, Browse, Arrow and Crux – vying for FID."

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