Prelude FLNG

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NamePrelude FLNG
OwnerShell plc
Port of registryFremantle, Australia
BuilderSamsung Heavy Industries, Geoje Shipyard, South Korea
CostUS$10−13 billion
Laid downOctober 2012
LaunchedDecember 2013
CompletedJuly 2017
Maiden voyageJuly 2017
In service2018
IdentificationIMO number9648714
General characteristics
TypeFloating production storage and offloading
Tonnage300,000 GT[2]
Displacement600,000 tonnes[1]
Length488 m (1,601 ft)
Beam74 m (243 ft)
Height105 m (344 ft)

Prelude FLNG is a floating liquefied natural gas platform owned by Shell plc and built by the TechnipSamsung Consortium (TSC) in South Korea for a joint venture between Royal Dutch Shell, KOGAS, and Inpex.[3][4] The hull was launched in December 2013.[5]

It is 488 metres (1,601 ft) long, 74 metres (243 ft) wide, and made with more than 260,000 tonnes of steel.[6] The vessel displaces around 600,000 t when fully loaded, more than five times the displacement of a Nimitz-class aircraft carrier.[7] It is the world's largest floating liquefied natural gas platform as well as the largest offshore facility ever constructed.


The main double-hulled structure was built by the Technip Samsung Consortium in the Samsung Heavy Industries Geoje shipyard in South Korea. Construction was officially started when the first metal was cut for the substructure in October 2012. The Turret Mooring System has been subcontracted to SBM and has been built in Drydocks World Dubai, United Arab Emirates. The MEG reclamation unit by Fjords Processing Norway and built in South Korea is the only topside module subcontracted. Other equipment such as subsea wellheads are being constructed in other places around the world. It was launched on 30 November 2013 with no superstructure (accommodation and process plant).[8]

The vessel is moored by its turret to 16 seabed driven steel piles, each 65 meters long and 5.5 meters in diameter.

Subsea equipment is being built by FMC Technologies, and Emerson is the main supplier of automation systems and uninterruptible power supply systems.[9] By July 2015, all 14 gas plant modules were installed.[10]

Cost and funding[edit]

Prelude FLNG was approved for funding by Shell in 2011.[11]

Analyst estimates in 2013 for the cost of the vessel were between US$10.8 to $12.6 billion.[5] Shell estimated in 2014 that the project would cost up to US$3.5 billion per million tons of production capacity. Competitive pressures from an increase in the long-term production capabilities of North American gas fields due to hydraulic fracturing technologies and increasing Russian export capabilities may reduce the actual profitability of the venture from what was anticipated in 2011.[11] In 2021 the WAToday news website reported that it was believed that the ship had cost at least US$17.5 billion, though Shell has never confirmed the actual cost.[12]


The Prelude FLNG system was built for use in the Prelude and Concerto gas fields in the Browse LNG Basin,[9] 200 kilometres (120 mi) off the coast of Australia; drilling and gas production were planned to begin in 2016.[5][11] The system has a planned life expectancy of 25 years.[13] The Prelude and Concerto fields are expected to produce 5.3 million tonnes of liquid and condensate per year; this includes 3.6 million tonnes of liquified natural gas, 1.3 million tonnes of condensate, and 400,000 tonnes of liquified petroleum gas.[14]

Natural gas will be extracted from wells and liquefied by chilling it to −162 °C (−260 °F).[14] The ability to produce and offload LNG to large LNG carriers is an important innovation, which reduces costs and removes the need for long pipelines to land-based LNG processing plants. However, fitting all the equipment onto a single floating facility was a significant challenge.

The system is designed to withstand Category 5 cyclones,[4] although workers may be evacuated before that on an EC225 rescue helicopter.[15] According to plans, it will produce 110,000 BOE per day.[16]

On 25 July 2017, after a journey of 5,800 km (3,600 mi) from its construction site in South Korea, Prelude arrived on site in Western Australian waters. It was expected to become operational in 2018.[17][18] On 26 December 2018, Royal Dutch Shell announced that initial production had begun at Prelude. Shell said that wells had been opened and that the start-up and ramp-up phases were underway.[19]

Prelude was shut down in February 2020 after a reported electrical problem. The platform had previously suffered two incidents that saw the unintended release of gas, which NOPSEMA described as "dangerous".[20] It restarted production in January 2021.[21][12]

The ship's electrical supply was disrupted by a small fire on 2 December 2021. This led to the cessation of production and the evacuation of most of the crew.[12][22]

As a result of repeated environmental and safety mishaps, NOPSEMA ordered the supermajor to not resume production for an indefinite period of time, pending Shell's ability to prove updated practices. According to NOPSEMA, Shell "did not have a sufficient understanding of the risks of the power system on the facility, including failure mechanisms, interdependencies, and recovery", adding that "power loss directly impacted critical safety systems along with the ability to safely evacuate crew by boat or helicopter."[23]

In April 2022 the vessel resumed operations.[24] Operations were again partially stopped and then fully stopped during a strike which lasted 11 weeks until 25 August 2022.[25]

A Lego model of Prelude was built for a Shell trade show in 2014.[26] Nearly 5 meters long, the model currently resides in the foyer of Shell's Perth head office.


  1. ^ a b Summers, Chris (15 July 2011). "The gas platform that will be the world's biggest 'ship'". BBC News. Retrieved 17 December 2014.
  2. ^ "Prelude - 9648714 - Floating Storage/Production". Maritime Connector. Retrieved 17 December 2014.
  3. ^ "Steel Cutting for Prelude FLNG Begins in South Korea". Offshore Energy (Press release). 18 October 2012. Archived from the original on 29 October 2013. Retrieved 28 October 2012.
  4. ^ a b "Shell's massive Prelude hull world's biggest-ever floating vessel and first ocean-based LNG plant". Financial Post. Reuters and Associated Press. 3 December 2013. Archived from the original on 4 December 2013. Retrieved 5 December 2013. Shell said Tuesday that the 488-metre (1,600 foot) hull of the structure, known as Prelude was floated out of the dry dock in Geoje, South Korea where she is being built.
  5. ^ a b c "Shell's record-breaking Prelude takes to the water". BBC News. 4 December 2013. Archived from the original on 4 December 2013. Retrieved 4 December 2013.
  6. ^ Newnham, Danica (18 October 2012). "Construction of Prelude FLNG begins". Upstream. Archived from the original on 24 November 2012. Retrieved 28 October 2012.
  7. ^ DeHaemer, Christian (28 July 2011). "The Prelude FLNG Project". Energy & Capital. Retrieved 28 October 2012.
  8. ^ "Prelude Project milestones". Shell Australia. Retrieved 17 September 2015.
  9. ^ a b "Shell's Prelude FLNG Project, Browse Basin, Australia". Offshore Technology. Retrieved 28 October 2012.
  10. ^ Sustaita, Melissa (8 July 2015). "Prelude topsides installed". Asian Oil & Gas. Retrieved 17 September 2015.
  11. ^ a b c Kelly, Ross (19 June 2014). "GDF Suez, Santos Halt Innovative LNG Plan in Australia : Companies Say Offshore Conversion Project Not Commercially Viable". Wall Street Journal. Retrieved 30 December 2014. Shell approved construction of the world's first floating LNG vessel in 2011 to process gas from the Prelude field, also located off Australia's northern coast. The giant vessel—longer than four soccer fields when laid end to end—is being built in a South Korean shipyard and is scheduled to start producing LNG in 2016. ... Shell has estimated its Prelude project will cost up to $3.5 billion for each million tons of production capacity, indicating a total cost of up to $12.6 billion.
  12. ^ a b c Milne, Peter (3 December 2021). "Shell's giant $24b Prelude LNG ship shut down after fire". WAtoday. Retrieved 5 December 2021.
  13. ^ Savov, Vlad (5 December 2013). "Made by Samsung, Shell's Prelude is an Empire State Building on water". The Verge. Archived from the original on 6 December 2013. Retrieved 5 December 2013.
  14. ^ a b "Shell's Prelude FLNG Project, Browse Basin, Australia". Offshore Technology. Retrieved 9 October 2015.
  15. ^ Prelude's "super" chopper Video by Shell, 24 March 2015.
  16. ^ "Shell's massive Prelude hull world's biggest-ever floating vessel and first ocean-based LNG plant". Financial Post. Reuters and the Associated Press. 3 December 2013. Retrieved 30 December 2014.
  17. ^ "Prelude floating LNG facility arrives in Australia". Oil & Gas Journal. 25 July 2017. Retrieved 24 October 2017.
  18. ^ "Shell's Prelude FLNG Reaches Australian Waters". The Maritime Executive. 25 July 2017. Retrieved 24 October 2017.
  19. ^ Jaganathan, Jessica (26 December 2018). "World's largest floating LNG platform starts production in WA". Sydney Morning Herald.
  20. ^ Collins, Ben (21 August 2020). "World's largest floating LNG factory remains in shutdown — at just three years old". ABC News.
  21. ^ Collins, Ben (24 January 2021). "LNG production at Shell's Prelude gas processing plant in Western Australia restarts following 11-month closure". ABC News.
  22. ^ Snow, Madison (5 December 2021). "Shell's Prelude LNG vessel shuts operations, staff evacuation underway after electrical fire". ABC News. Retrieved 5 December 2021.
  23. ^ "The Many Growing Pains of Shell's Prelude FLNG Continue". JPT. 2022-01-04. Retrieved 2022-05-22.
  24. ^ Paul, Sonali (2022-04-11). "Shell resumes shipping LNG from Prelude off Australia". Reuters. Retrieved 2022-06-18.
  25. ^ "Shell reaches deal with unions to restart Prelude FLNG". 25 August 2022. Retrieved 7 September 2022.
  26. ^ "Throwback Thursday Lego Brick Shell's Prelude FLNG Facility". Brickman. 12 October 2017.

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