Written by Jeremy Cresswell -
Energy Voice has teamed up with Shell to celebrate 40 years of Brent. This promoted series will examine the people, milestones and technology that helped make this historic North Sea find possible. It will also analyse what lies ahead for the breakthrough discovery. Happy 40th Brent!
As things stand today, what is the schedule for removal of the first topsides looking like?
Well, it turns out that the timetable is relatively relaxed.
What matters is getting everything right, including waiting for a decent “weather window”; one with wriggle room.
“Brent Delta is currently sitting there, unmanned,” says Brent decom manager Duncan Manning.
“All preparations are complete and it’s sitting out there waiting to be lifted. The focus is therefore now on the vessel and ensuring that changes that need to be made following the Talisman
Yme platform topsides removal prior to lifting the Brent Delta topsides are carried out.
“This includes installing additional lifting arms, which sounds straightforward but isn’t.
“These are 65m, 2,000-tonne beams and we need 16 of them for Brent Delta. They all need to be integrated so they work together.
“But, because the platform is no longer manned, we’re not schedule-driven. This is about doing the lift at the right time; when the vessel is right and when offshore conditions are right too.”
Meanwhile, Shell has a full safety case for leaving the platform in an unmanned state.
“We’re remotely monitoring the platform …we don’t need personnel on the platform doing that,” says Manning.
“So we have an assurance that, when the vessel arrives in-field to do its job, we’re good to go.”
All things being equal, the first lift opportunity should present itself in the Spring. A weather window of three to five days will be required and Brent Delta will be the largest platform topsides ever lifted in the history of the offshore industry.
Because this is not schedule-driven, the team doesn’t need to push the weather boundaries to get it done.
Assuming a smooth lift and parking of the topsides on the Allseas vessel’s own cargo-barge called Iron Lady, then the hefty load will be towed to Teesside for skidding ashore at Able’s new deepwater decom facility.
“The next step after that is that we will carry out a full survey of the platform,” says Manning.
“We’re then going to have an open-day to allow both local residents and those who have worked on the platform in the past to show friends and family what had been their workplace at one time.
“After that, it is up to Able to determine what components will be recycled for re-use, then do a soft strip and a hard strip followed by full destruct of the topsides. Expectation is that 97% of materials (mostly steel) will be recycled.”
Then what? What are the likely next step?
Teams are currently completing reservoir isolation on Brent Bravo and are about to start that process on Brent Alpha, plus Charlie.
There will be continual activity on all three of the remaining platforms.
“But, before we lift anything else, we will be looking at what lessons can be learned from Brent Delta in terms of its preparation and removal.
“The next big milestone will be submission of the decommissioning plan, bearing in mind that, at the moment, we only have an approved decom plan for Delta.
“The hope is that it will go in for public consultation in the not too distant future. We’ve extended the consultation period from the required 30 days to 60 days to allow people more room in
which to comment.
“That, in turn, will set the timeline for the removal of further Brent infrastructure.”
However, a second lift next year is considered unlikely; indeed it seems that one heavy-lift a year could become the pace of removal.
There is a perception that the decommissioning of a platform topsides is a huge, huge scope of work, which it is.
But if this is viewed in the context of the totality of the decom of Brent, the topsides piece is probably 2-5%, according to UK & Ireland upstream VP Paul Goodfellow.
It is worth remembering that this is the industry that is out of sight, out of mind – no-one cares about it except those who work within it.
That potentially makes decom a really difficult sell, as confirmed by Manning and, of course, Shell was badly shaken by the Brent Spar debacle of the mid-1990s.
Manning: “I’ve spent a lot of my time speaking with stakeholders who aren’t necessarily versed in oil & gas; trying to convey the scale of what we are doing with the Brents …or example a
300,000-tonne gravity topsides built at the height of the UK’s 1970s energy crisis was not designed to be removed.
“When you put it this way, the penny tends to drop that this is a very large engineering challenge,” Manning confirms.
To celebrate and capture the rich history of Brent, Shell is commissioning an e-memory book and an oral history project. If you have an unforgettable Brent story, or have an old photo or memory you would like to share, you can submit them at www.shell.co.uk/brentmemories. The oral history project will be interviewing a selection of candidates from a variety of roles and years to record the highlights and uncover the less widely known stories from the last 40 years. Digital recordings will be donated to The University of Aberdeen who will share these stories with anyone who is interested, from family members and researchers, to students and the public. Please contact Brentinfo@shell.com if you would like more information about these projects.