* Shell aims to start exports from Prelude LNG this year
* Inpex hopes to commence shipments from Ichthys LNG
* The two gas fields offshore Australia overlap
* Both projects have been plagued by delays, cost overruns
By Henning Gloystein
SINGAPORE, April 24 (Reuters) - Shell and Inpex are on thefinal stretch of a years-long race to export gas from offshorenorthern Australia, where both have spent billions of dollarsbuilding the world's biggest maritime vessels to grab a slice ofAsia's booming LNG market.
Anglo-Dutch energy major Royal Dutch Shell andInpex, Japan's biggest oil and gas producer, are vying for firstgas from two overlapping fields after delays and cost overrunsthat have plagued both projects.
The pair have spent billions on offshore facilities,including Shell's 490 metre (1,600 ft) long Prelude floatingliquefied natural gas unit and Inpex's Ichthys Explorersemi-submersible platform, both the world's largest of theirclass.
Inpex also has the 340 metre-long Ichthys Explorer, afloating LNG production and storage unit, built in South Korea,in parallel with Shell's Prelude.
"Prelude and Ichthys are both record breaking mega-projectsthat have been competing throughout their development," saidSaul Kavonic or energy consultancy Wood Mackenzie.
Both arrived on site last year and are about to receivewhat's known as a "cooling cargo" of liquefied natural gas(LNG), which indicates a plant is getting closer to startingoutput.
The delivery is used to chill the facilities ahead ofregular production of LNG, which is shipped at a temperature ofminus 160 degrees Celsius.
The race means more than just pride as the Prelude andIchthys fields straddle the same gas in the Browse Basin,according to WoodMac.
"Their reservoirs are connected, meaning whichever projectstarts producing first will draw some gas away from the otherproject," Kavonic said.
Ship tracking data in Thomson Reuters Eikon shows the'Gallina' LNG tanker arrived at Prelude in mid-April in order todeliver a cooling cargo, while the 'Pacific Breeze' is due toarrive at the Ichthys field from Malaysia this week.
Both projects are still preparing for export, but Shell isgrappling with the challenges of commissioning a brand newtechnology.
"We currently assume first cargo from Ichthys in Q3 and fromPrelude in Q4, with risk of further delays," said Kavonic.
A Shell spokeswoman reiterated that the oil major expects toget cash flow from Prelude in 2018.
Inpex has said it expects a start-up at Ichthys, initiallydue in 2016, in April or May.
"There is no change to the schedule that we announced inMarch," Inpex spokesman Carlo Niederberger told Reuters.
Although both projects feed from the Browse Basin, Inpexsaid it was not yet certain whether there would be directcompetition for gas between the two fields.
EXPENSIVE & LATE
Prelude - which will produce, process and export LNG - cameat a cost of more than $13 billion, several years late andbillions of dollars over initial estimates.
Prelude is expected to have an annual LNG productioncapacity of 3.6 million tonnes, making it the smallest but mostchallenging Australian LNG project in recent years.
Ichthys will send gas onshore to Darwin through an 890-km(550 mile) pipeline, where it will be processed into LNG forexport. Once completed, the $40 billion project will have anannual LNG capacity estimated at nearly 9 million tonnes.
Both Prelude and Ichthys will also produce condensate, anultra-light form of crude oil, as well as liquefied petroleumgas (LPG).
Exports from new LNG projects including Ichthys and Preludeare expected to help Australia overtake Qatar to become theworld's largest LNG exporter by the end of the decade.
(Reporting by Henning Gloystein, Jessica Jaganathan inSINGAPORE, Osamu Tsukimori and Aaron Sheldrick in TOKYO; writingby Henning Gloystein; editing by Richard Pullin)
