With Pieter Schelte, the figures alone are impressive. 382m long, 124m wide and with a slot width of 59m it can remove topsides up to 48,000 tons in a single lift, potentially revolutionizing large decommissioning projects. The new vessel is able to replace the previous slower method of removing topsides piece by piece with one lift, meaning a decommissioning job could be done in a fraction of the time.
Outside of the Gulf of Mexico (where NTL2010-G05 makes it mandatory) and some other shallow-water areas, decommissioning has been infrequent, with the busy North Sea seeing few decommissioning jobs despite a number of platforms being well beyond their design life. That is set to change and the Pieter Schelte should be on the front line of a more concerted effort to remove platforms in the region.
The opportunity is significant – in the North Sea 478 platforms may need to be removed before 2045. The vessel has already won a number of contracts with removing three platforms from the Brent field up first. Along with this, the versatile vessel will be laying 890km of trunkline for the South Stream project. In the latest edition of its Subsea Vessel Report Douglas-Westwood forecasts that $9.75 billion is to be spent installing pipelines globally between 2015 and 2017, demonstrating that the potential is there for significantly more work in both applications in the coming years.
All of this points towards good early signs that building the vessel will prove to be a smart move from Allseas, despite worries over pricing contracts that take a long time to plan but far less to complete. Ultimately, however the impact the Pieter Schelte will depend on cost and demonstrable ease of use in an industry that is inherently cautious when it comes to trying new things (Shell spent four years studying the ship before awarding the Brent decommissioning contract).
The possibility of this starting a trend remains to be seen – will other players decide to build similar vessels after seeing it in action for the first time in May 2015? Allseas themselves appear confident that the Pieter Schelte will be a success with another decommissioning vessel able to lift a staggering 72,000 tons already planned.
By Ben Wilby, Douglas-Westwood Faversham