Customers in the offshore industry don't mind being second when it comes to new technology.

Why did it take 10 years for Aker to get the SPAR concept accepted in the Gulf of Mexico? And why did it take years from when Golar-Nor introduced the first floating production, storage and offloading (FPSO) vessel in the North Sea till the FPSO concept got generally accepted? Why is it that when the automakers introduce a new automobile, the customers line up to be first to get the new model? But when the offshore industry introduces a new concept, the customers line up to buy number two. Few oil companies want to take the risk, however small, to be first to try new technology. Proven, proven, proven. That's the magic word.

Despite the conservatism, the offshore industry has come a long way in developing new technology. Deepwater fields, horizontal drilling, enhanced recovery, sub-sea separation, etc. etc. The benefits to the oil companies in making use of new technology have been enormous. And many oil companies, in partnership with the supplier industry, have led the way in developing new technology. And the suppliers, driven by their desire to be constantly better, are striving to develop new and more efficient technology to meet the world energy needs.

Sometimes, it is just not good enough to make existing solutions bigger, or taller, or stronger, or faster to meet the challenges of taking the industry forward. There is a reason why we don't fly in 5,000 passenger airplanes, or don't cruise across the oceans in 500 knot vessels, or don't build 4,921-ft (1,500-m) tall offshore platforms. Sometimes we need step-change technology to take us across the barriers.

HiLoad

HiLoad is a new concept for offshore loading of crude oil. HiLoad was developed as an answer to the oil companies' wish to be able to load any tanker at any offshore location regardless of water depth, and without any special equipment on the tanker. HiLoad has no mooring system. It keeps the tanker in position by thrusters and dynamic positioning. This means that the deeper it gets, the more competitive HiLoad becomes, as it has no expensive mooring system and no associated installation cost.
HiLoad is remotely operated. The thrusters, ballast system, position reference systems, and all other systems are remotely controlled from the Cyberbase control station on the FPSO. More than 300 cyberbase control stations are delivered and in operation for control of drilling rigs, remotely operated vehicles (ROVs) and vessels worldwide. It is proven.

HiLoad is like a forklift truck. Imagine a forklift truck floating in the sea. That is HiLoad. When the tanker approaches the field, HiLoad swims towards the tanker until eventually the large soft fenders on the vertical towers make contact with the side of the tanker. The ballast tanks are emptied within 2 minutes, and the horizontal "fork-plate" makes contact with the underside of the tanker. The impact is soft, as the entrapped water between the hull and the HiLoad provides a giant cushion.

Once HiLoad has made contact underneath the vessel, the attachment system, consisting of friction pads surrounded by rubber seals, is activated. The water inside the six friction cells is pumped out, and the cells are connected to the atmosphere. The static head thereby generated in combination with the friction material inside the cells, provides a horizontal holding capacity of 1,500 to 2,500 tonnes, pending on vessel draft. This is more than 15 times what is required, and ensures that HiLoad and the vessel becomes and moves like one unit. HiLoad is now taking control of the station keeping, and the DP system keeps HiLoad and the tanker within defined operational limits throughout the loading operation.

The loading hose is kept on a reel onboard HiLoad, and the hose end is easily winched to connect to the tanker's midship manifold for loading.

Onboard the FPSO are the cyberbase control station, the crude oil export line and metering station, and necessary power supply. The crude is pumped from the FPSO to the tanker via HiLoad through two 16-in. or one 19-in. flexible low pressure riser. There are two umbilicals, comprising power, control and fiber optical cables, to provide full redundancy. The capacity is sized to load a 1 million bbl-size tanker in 24 hours.

Prior to HiLoad connecting to the tanker, the mooring master boards the tanker, as with conventional loading from a SPM, and stays onboard the tanker for the duration of the loading period. The mooring master is in radio contact with the HiLoad Pilot at the cyberbase control station on the FPSO, and can initiate emergency disconnection procedures at any time.

HiLoad has a turret and swivel arrangement allowing the connected tanker to weathervane 360°. Space is allocated for a pig receiver. The loading hose from HiLoad to the mid ship manifold on the tanker is equipped with an integrated fail-safe valve to avoid any oil spill during a quick disconnect.

When the tanker is fully loaded, the loading hose is emptied and reeled back to HiLoad. The Attachment system is deactivated, ballast water is let into the tanks, and HiLoad quickly disengages from the tanker, which is free to start its voyage to the crude receiving terminal.

Between loadings, HiLoad floats with a draft of 82 ft (25 m), minimizing the environmental loads. It carries the weight of the unsupported portion of the riser and umbilicals. A parking system designed to withstand a 100 years return condition keeps the HiLoad in position. The parking line configuration allows HiLoad to move relatively freely within the operational sector. The lines will gradually tighten as the HiLoad approaches the operation sector limits, preventing HiLoad from drifting out of the operational envelope. Alternatively, HiLoad can be parked on the FPSO between loadings.

Reliability

HiLoad is designed to DNV's Rules for Mobile Offshore Units, and both DNV and ABS have issued "Approval in Principle" certificates. Full redundancy has been an important design criteria, and all systems on HiLoad are fully redundant. DNV recently carried out an in depth reliability and availability analysis concluding with 99.8 % availability for HiLoad.

HiLoad is equipped with three thrusters of 2 MW each. Even with one thruster out of operation, the HiLoad maintains 100% thrust capacity. The ballast system enables HiLoad to be deballasted to a draft where the attachment system is above water for easy inspection and repair. HiLoad is in principle a vessel, designed and shaped to do a specific task only, and it can be docked for periodic inspection and repair, just like any other vessel. If no docks are available, HiLoad may be brought totally out of the water by a submersible barge. The dry weight of HiLoad is 2,200 tonnes.

Extensive testing of docking and station keeping capabilities has been carried out at Marintek in Norway, as well as wind tunnel testing and full scale prototype testing of the attachment system. These tests verify that docking can be carried out in 1-year return conditions in areas like West Africa, Brazil and Gulf of Mexico, and the DP system keeps a VLCC in position in 1-year return conditions with only half of the thruster capacity utilized. The attachment system is proven to have a holding capacity of more than 15 times what is required.

Cost

An investment in HiLoad is an investment in a vessel. HiLoad may be used for longer or shorter periods at a specific field, and it may easily be relocated to other fields. With other deepwater crude oil export systems, a major part of the investment is in the mooring system and the installation of the system. With HiLoad, the investment is in the device itself, and this cost compares favorably with other alternatives.
HiLoad, with its thrusters and DP2 capability requires no additional tugs to maneuver the tanker and hold it within operational limits during loading. Hence the daily operating cost of a HiLoad export system is low.
Adding capital expenditures and operating expenditures, HiLoad has an advantage of at least US $50 million. Net present value compared to existing systems. To reduce up front investment, HiLoad can also be leased on a time charter basis.

Oil company support

HiLoad is developed in close co-operation with ConocoPhillips Marine Department and is partially funded by ConocoPhillips. Patents for the HiLoad concept and the attachment system are pending in a number of countries world wide, and the first patent has been granted in Nigeria. Detailed engineering of the unit is completed, and the first HiLoad can be deployed in the field 12 to 18 months from order.
Is HiLoad new technology? HiLoad is a vessel. It consists of only proven components and systems. Its thrusters, DP system, control system, its seals and rubber friction materials, its position reference systems and cameras, its pumps and valves have all been used tens and hundreds of times before, and it all comes from world leading suppliers. The shape of the hull is new, but it is simply steel welded together to form a shape ideally suited to perform this vessel's single task: To connect to the tanker, keep it in position and load that valuable crude oil.

Sometimes a step-change is necessary.

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