Major subsea contract for Senegal’s first oil development

The contract, valued between US$500M and US$750M, was initially awarded in December 2018 subject to FID, which has now occurred.

Confirmation of the award follows approval of the US$4.2Bn project by the Senegal Government. It is the country’s first offshore oil development. Phase 1 of the development will target an estimated 231M barrels of oil resources, with first oil targeted for 2023.

Developing the project is the Rufisque Offshore, Sangomar Offshore and Sangomar Deep Offshore (RSSD) joint venture (JV), comprising Capricorn Senegal Limited (a subsidiary of Cairn Energy PLC), Woodside Energy (Senegal) BV, Far Ltd and Petrosen (the Senegal National Oil Company).

As the operator of the RSSD JV, Woodside has executed the purchase contract for a floating production storage and offloading (FPSO) facility and issued full notices to proceed for the drilling and subsea construction and installation contracts.

MODEC will supply an FPSO with an oil processing capacity of 100,000 bbl/day, 130M standard cubic feet (scf) of gas per day, 145,000 barrels of water injection per day and will have minimum storage capacity of 1.3M barrels of crude oil.

Scheduled for delivery in early 2023, the FPSO vessel will be permanently moored in 780 m of water approximately 100 km off the coast of Dakar. The vessel will be moored via an external turret mooring system to be supplied by Sofec, a MODEC group company.

Diamond Offshore has been awarded two well-based contracts for the drillships Ocean BlackRhino and Ocean BlackHawk.

Under its contract, the Subsea Integration Alliance will provide the engineering, procurement, construction, transportation and installation of the SURF system and associated subsea production systems. The development will include 23 wells, 107 km of rigid flowlines, 28 km of flexible risers and jumpers, and 45 km of umbilicals in water between 700 m and 1,400 m.

Offshore activities will take place from 2021 to 2023 using Subsea 7’s reel-lay, flex-lay and light construction vessels.

Subsea Integration Alliance, which teams Subsea 7 and OneSubsea, the subsea technologies, production and processing systems division of Schlumberger, was established during the front end engineering design (FEED) phase, which will now transition into the full EPIC phase based at Subsea 7 Global Projects Centre (GPC) in Sutton, UK. SURF engineering will be performed by Subsea 7 GPC centres in Sutton and Suresnes, France. A base in Senegal will support the offshore campaign and conduct site receipt testing and equipment storage.

Subsea 7 vice president Africa region Gilles Lafaye said “Subsea 7 brings decades of experience in working safely and reliably in the region as well as bringing global engineering and execution capabilities to support Senegal as it increases energy production.”

Subsea Integration Alliance deputy chief executive Stuart Fitzgerald said “Subsea 7 and OneSubsea, through our Subsea Integration Alliance, have been working closely with Woodside since before the FEED award. This award reflects our successful experience of previous projects delivered by the alliance and a strong relationship built over many years with Woodside.”