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SUBSEA FACTORY ballasted solid protection structure, into which seawater is al- them at US$50/bbl you need a solution that has 50% of the lowed to ? ow, ? lling or exiting the structure, never in contact capex and opex cost of present day FPSOs (? oating produc- with the oil. The bag and center pipe can be retrieved. tion, storage and of? oading vessels). SeaCaptaur thinks the

Kongsberg designs the SSU (subsea storage unit) system North Sea has the most potential in terms of producing its from the riser, from a topsides facility where it has been small pools. But, Roberts says, “there’s a cultural problem. through separation, to of? oading via shuttle tanker, through separation, to of? oading via shuttle tanker, They [North Sea operators] only understand big. They need They [North Sea operators] only understand big. They need to ensure that the time it takes to export the oil to ensure that the time it takes to export the oil to scale down right down to small and basic.”to scale down right down to small and basic.” and heat management meets the requirements of and heat management meets the requirements of SeaCaptaur has drawn on the Apache (Australia) SeaCaptaur has drawn on the Apache (Australia) the speci? c ? eld. The SSU has integrated the speci? c ? eld. The SSU has integrated and Sasol (South Africa) control buoy systems, and Sasol (South Africa) control buoy systems, sensors, barrier philosophy sensors, barrier philosophy the Khazzan oil storage tanks and the the Khazzan oil storage tanks and the and operational management and operational management Prinos tank. It has a base case Prinos tank. It has a base case ensuring full overview of ? ll- ensuring full overview of ? ll- 50,000 bbl oil storage tank on 50,000 bbl oil storage tank on ing, discharge and thermal ing, discharge and thermal the sea? oor. The tank would be the sea? oor. The tank would be performance of the system, performance of the system, ? oated out using a tug and then ? oated out using a tug and then says Kongsberg. ballasting for positioning. The ballasting for positioning. The

The project was given tank would be connected, us-tank would be connected, us-

Demo 2000 funding and ing tethers, to a rigid mono-ing tethers, to a rigid mono- is part of a joint indus- lithic production spar buoy, try project with Statoil, which pierces the surface

Det Norske, Lundin, and for gas ? aring and offtake. the Research Council of The buoy would contain four

Norway. As part of the levels, or decks, containing the levels, or decks, containing the

DEMO 2000 funding, test- processing systems – which processing systems – which ing was carried out on a could support electric submers-could support electric submers- 1/9 scale model. ible pumps. Access for mainte-ible pumps. Access for mainte-

Kongsberg’s subsea oil storage

Kongsberg is looking to nance would be via an access nance would be via an access tank concept. Image from Kongsberg. offer similar technology for sub- offer similar technology for sub- gangway, the like those being gangway, the like those being sea chemical storage and produced water storage. used in the offshore wind industry.

The system would require a specialized, 65,000 bbl capac-

Seacaptaur ity shuttle tanker for offtake. SeaCaptaur has designed a DP

Australian ? rm SeaCaptaur has another solution. Alan shuttle tanker for this job, complete with motion compensated

Roberts, the ? rm’s managing director, and Max Begley, of gangway, which could in effect do a milk round of several

Matrix Composites & Engineering, joined forces to create a facilities and take the crude straight to the terminal, to avoid system to develop small pools. third party lifting charges or tariffs.

SeaCaptaur is focusing on ? elds containing 5-15 MMbbl “It is still cheaper than a FPSO,” but, you have to have a recoverable in 10-300m water depth. Roberts says there’re number of small pools running, say 2-3, to maintain a produc- around 2000 small pools around the world, but to develop tion rate of 10-11,000/d, to make it work, Robert says.

Relying on infrastructure

MMbbl, are within 50km of a pipeline – although what type of pipe-

While there is a large prize to be had in the UK North Sea’s small line this was needs de? ning in further work. Some 80% contained pools, individually it’s hard to make these small reservoirs pay less than 20 MMbbl but were less than 10km from a pipeline. their way. By far, most of the opportunities are in

According to a University of Aberdeen report looking at the pos- the central North Sea, followed by west of sible pro? tability of small pools (containing 3-15 MMbbl recover- Shetland and then the northern North Sea. able), at $60/bbl, the smallest size pool that becomes economic “The central North Sea and northern North is 11 MMbbl. Sea is where there is already a lot of infra-

The current technology to develop such a ? eld is a single well, structure,” Blake says. “There is not a lot of with a single ? owline, a single umbilical for tieback to a host. But, infrastructure west of Shetland.” “if we could cut the cost by 25%, it would take the ? eld size to 9 “There is a possibility to hook this stu