OFFSHORE EXPERT: “Having read this Prelude document a few times to take it all in, it seems to me that the main issue is how do you design for a 10,000 year event?” COMMENT: “I am not an expert and would only say that so-called 10,000 year weather events seem to be occurring annually at the moment. If Noah was still around, and residing in Southern England, he might well be looking for his carpentry tools.”
COMMENT FROM A RETIRED SHELL OFFSHORE MANAGER
Regarding recent discussions on this website about Shell Prelude FLNG project, information available via this link provides useful input.
The 28 page section of a 75 page Shell document gives a description of the development and goes into great detail, providing answers to most of the issues raised by a fellow Shell Retiree.
Having read this Prelude document a few times to take it all in, it seems to me that the main issue is how do you design for a 10,000 year event?
The many issues raised with respect to cyclonic activity, waves, wind and the ability to weather vane are answered. There are two thrusters located near the stern with a total power of 6 megawatts or 8,000 HP. More than ample to ensure the heading of the facility is optimum at all times. Other issues with respect to Green house gas emissions during operations and other environmental are dealt with in detail.
Lloyds Register have been active by drawing up rules for the construction of such large hulls. A presentation given by Lloyds to the Industry is available via this link who also make reference to a hull design for a 10,000 year event. The end result will be akin to a “brick nettie”
Perhaps my fellow Shell retiree would be interested in this?
Where Shell have a proven track record of questionable Competence is centred around the Operations of facilities where a plethora of shortcomings continues to be demonstrated to all and sundry, not only locally but on a global scale.
COMMENT BY JOHN DONOVAN
Many thanks. The further information about Prelude is helpful and no doubt will be taken into account by Bill Campbell, retired HSE Group Auditor for Shell International, who I am hoping will provide his opinion for publication. I am not an expert and would only say that so-called 10,000 year weather events seem to be occurring annually at the moment. If Noah was still around, and residing in Southern England, he might well be looking for his carpentry tools. The flooding has been described by PM David Cameron as of biblical proportion.
COMMENT FROM “RELIEVED,” ANOTHER FORMER SHELL EMPLOYEE
Personally, I think the real issue with the Prelude is long term maintenance. RDS has shown a predisposition to get cheap when equipment begins to wear out. We have seen this in the North Sea and elsewhere. However, fixed platforms usually don’t sink. There is a good chance RDS can put the Prelude on the bottom if they play their ‘Touch F** All’ games with maintenance on this vessel.
COMMENT BY “WASHINGTON OBSERVER”
For all you Prelude fans out there I have a bit of sobering information. The reason the US Navy does not built aircraft carriers any larger than they do is because they don’t know how to do it. The issues for the Navy are dynamics, i.e., shock and vibration, and long term hull maintenance. Hulls have a service life that is fatigue related. The harder you work a ship the shorter the hull life. If the US Navy doesn’t know how to built mega-ships what makes Shell think a South Korean shipbuilder and consultants know how ????
FURTHER COMMENT BY “RELIEVED”
Read the most recent comments about the Prelude. The comments about ‘rogue’ waves was interesting. I don’t know what the data for SE Asia are, but I do know that rogue waves in excess of 35 meters have been documented in the North Sea. There is plenty of data available from some of the oil/gas production platforms located there. I also know the US Navy has compiled data about rogue waves for various locations about the world. Someone might try contacting the US Office of Naval Research or the National Oceanographic and Atmospheric Admin. to see if that data is available.