A groundbreaking offshore construction vessel is being used for a Gippsland Basin decom contract, which will provide a safer and more cost-effective removal of platforms.
The Esso Australia Pty Ltd (Esso Australia), a subsidiary of ExxonMobil Australia, recently awarded Switzerland-headquartered Allseas, a leading contractor in the offshore energy market, the contract to remove up to 12 retired platforms from the Gippsland Basin in the Bass Strait, with a combined weight of approximately 60,000 tonnes. It covers up to 12 topsides and up to 11 steel jackets.
Allseas will utilise the Pioneering Spirit, which the company says is the largest, most versatile offshore construction vessel in the world, designed for the single-lift installation and removal of offshore platforms and the installation of record-weight pipelines.
The emergence of Pioneering Spirit sets new standards in offshore installation and decommissioning, according to Allseas. Capable of lifting entire platform topsides of up to 48,000 t and jackets up to 20,000 t in a single piece, it significantly reduces the amount of offshore work associated with installation and decommissioning, moving the work onshore where it is safer and more cost effective and reducing the time required to execute such contracts. The vessel set a new world record for the heaviest lift ever performed in July 2024, when it removed the last platform of the Shell Brent field in the North Sea, Brent Charlie, with topsides weighing 31,000 t.
Allseas plan to remove all the structures with Pioneering Spirit in just three to four months, starting late 2027. Once removed, the facilities will be transferred to barges or vessels for load-in to the Barry Beach Marine Terminal in Victoria for dismantling and recycling by a separate onshore contractor. Planning and engineering work is already underway.
