Allseas’ gargantuan catamaran, the Pieter Schelte, is not even built yet but the company has just announced it’s going to build one even bigger.
When Shell awarded Swiss-based Allseas Group the contract to remove, transport and load-in to shore the topsides of three of its Brent platforms in the North Sea using the huge Pieter Schelte, still under construction in Korea, it captured media attention around the world.
“Giant catamaran to carry worn out North Sea oil rigs ashore”, proclaimed Reuters, with similar headlines appearing in national newspapers globally.
Now, to meet predicted demand for removing large and complex offshore infrastructure (and maybe also because it loves the attention) Allseas has decided to build an even bigger single-lift platform installing and decommissioning vessel.
The new vessel, as yet unnamed, can remove all platform topsides in the North Sea which are beyond the capability of Pieter Schelte, Alsseas said.
Besides decommissioning, it will designed for worldwide installation of very large topsides.
Lift capacity will be 72,000 metric tons, exceeding the capacity of Pieter Schelte by 50%. The vessel will have a width of 160 m (525 ft), whereas Pieter Schelte is 124 m (406 ft) wide.
Allseas said the new vessel will be ready in 2020.
Shell’s Brent contract is the first to be awarded to Pieter Schelte, a dynamically positioned, single-lift installation, decommissioning and pipelay vessel currently under construction at Daewoo Shipbuilding and Marine Engineering in Korea.
With a length of 382m and width of 124m, the Pieter Schelte will have a topsides lift capacity of 48,000 tons and a jacket lift capacity of 25,000 tons.
ABB Consulting recommends that operators should make better preparations during the "lighthouse phase" to avoid cost increases when the time comes for full scale decommissioning.
On the 20th anniversary of Greenpeace’s campaign against the sinking of the Brent Spar platform, the oil and gas industry in the North Sea is still tied to a no dumping policy that makes “no scientific sense”, according to Shell’s former decommissioning manager.
Coupled with falling oil prices, decommissioning costs in the North Sea are coming up above the original budget. This puts operators with oil and gas platforms in the region, such as Shell whose Brent decommissioning project will take many years and accrue high costs, in a tight spot.