Built by Technip and Samsung Consortium in South Korea as a joint venture between the Royal Dutch Shell, KOGAS and INPEX, the Prelude FLNG marks the largest offshore facility ever constructed and the world’s second floating liquefied natural gas platform.
The enormous ship, costing $12 billion and built out of enough steel to build 36 Eiffel Towers, arrived in the Browse Basin, 475 kilometres northeast of Broome, after a month of being towed by tugs through international waters. 160 highly trained personnel remained on board during the journey to ensure the ship safely reached its destination. After completing work in the Browse Basin in 25 years, the Prelude will be capable of simply disconnecting and moving to a separate gas field in another part of the world.
The Prelude FLNG marks the largest offshore facility ever constructed and the world’s second floating liquefied natural gas platform.
Measuring an astounding 488 metres in length and 74 metres in width, and a weight of approximately 600,000 tonnes, the Prelude is the biggest vessel ever built. As a result of its size, it has created an immense learning curve for the trained personnel tasked with preparing the ship for operations.
“We have gained valuable experience through the development and construction of Prelude that can be applied both on and offshore to further improve integration and reduce costs,” says a Shell spokesperson. “For example, removing non-essential scope, building vertically to reduce plot size, applying the double mixed refrigerant liquefaction process and integrating effectively from the well head right to the LNG carrier.
The complexity of the facility is breath-taking. Floating LNG consolidates the traditional offshore to onshore LNG infrastructure into a single facility that is based over the fields. The FLNG facility gathers, processes, stores and offloads natural gas and condensate products at sea.” (Offshore Technology)
Estimated to process approximately 5.3 million tonnes of LNG per annum, the Prelude must now undergo rigorous and complex preparation before commencing operations. The Prelude will have 16 mooring chains attached to the 250-metre-deep sea floor to secure the 600,000-tonne vessel.
The Prelude will have 16 mooring chains attached to the 250-metre-deep sea floor to secure the 600,000-tonne vessel.
After the vessel is secured, the hook-up and commissioning phase will commence. The hook-up stage is expected to be the most laborious stage of the whole ordeal, with 1,500 personnel operating to ensure everything is prepared and secure. These individuals will be sourced from Perth, Darwin and Broome, which will become the base for marine and aviation services. It is estimated to take approximately 12 months to complete, as seven production wells and four flexible risers are prepared below the ship to prepare the natural gas before transporting it to the Prelude for storage.
Once operational, the Prelude will be running constant return flights via helicopter to the ship and have a staff roster of 250 Australians, with 120 to 140 personnel on the ship at any given time.
There has, however, been some scepticism around the economic proficiency of these floating liquefied natural gas platforms, especially a platform of the size and complexity as the Prelude.
During a Gastalk event, Saul Kavonic, Principal Analyst of Wood Mackenzie discussed the boom: “For me, 2017 was the year of FLNG. We saw the first ever delivery of LNG produced from Petronas, and Shell’s Prelude FLNG completed in the yards in Korea and begin commissioning. Mozambique has also taken to FLNG with Coral South, and its volumes are already secured.”
These FLNG projects were economically logical when first commission as the demand for oil was increasing at a price tag of US$100 a barrel. Floating LNG platforms had the capability to access extremely isolated assets at an increased speed and lower cost, with the ability to simply shift operations when the asset ran out.
These FLNG projects were economically logical when first commission as the demand for oil was increasing at a price tag of US$100 a barrel.
Now that the gas market has tightened and oil is sitting at around the US$60 mark, these enormous projects simply aren’t as cost effective as they used to be. “They will not achieve the return on revenue anywhere near what was first expected. There is the issue of cost challenges, and in the current market state we’re unlikely to see large-scale FLNG projects being sanctioned in next five to ten years,” said Mr Kavonic. (SMH)
Ultimately, the natural gas market will have the final say in future projects such as these – if the market remains steady large scale floating LNG platforms simply won’t be efficient. Nevertheless, if demand were to increase, so will the size of such projects, resulting in the construction of colossal vessels operating in increasingly remote stretches of sea.