Gjøa Field, North Sea Northern, Norway

Statoil's Gjøa field lies in blocks 35/9 and 36/7 of the North Sea. The field was proven in 1989. Reserves are estimated to be 82 million barrels of oil and condensate and 40 billion cubic metres of gas. Total Gjøa development investments are estimated at NKr29.3bn. After Snøhvit, this is the biggest project Statoil has under development.

Statoil awarded a three-year $427m drilling contract to Transocean Offshore covering of 13 wells, with options for a further three. The Transocean Searcher rig will drill the wells. First is planned to start in October 2008.

Plans envisage Gjøa to be developed with subsea templates tied back to a semi-submersible platform. Statoil has signed a contract with FMC Technologies for delivery of subsea systems.

DRILLING THE GJØA FIELD

In mid 2007, the Norwegian Storting (parliament) approved the Gjøa Plan for Development and Operation (PDO). The project is economically marginal, but made viable through tying back the Hydro-operated Vega and Vega South fields back to Gjøa.

The main power requirements will be derived from a land source which, according to Statoil, will have less of an environmental impact compared to a traditional solution with electricity produced at sea.

ABB Power Technologies will manufacture and install a 100km cable from Mongstad, north to the platform. This will make it the world's longest for transfer of high-voltage alternating current to floating installations.

The NKr500m contract will begin in 2009 with final tie-in to the field in 2010. Plans call for this to be coordinated with electricity production from the Mongstad energy project's (EVM) Combined Heat and Power (CHP).The reduction in carbon emissions from Gjøa at full production will equate to the emissions from 100,000 cars.

FLOATING PRODUCTION PLATFORM

The field will be developed with a floating production platform. The project consists of three main contracts. Aker Kvaerner will be responsible for the construction and assembly of the platform deck.

Statoil and Aker Kvaerner have signed the contract worth approximately NKr8bn for the semi-submersible platform to be located at the Gjøa field offshore Norway. The scope of work includes detail design of topside and hull, procurement, construction and hook-up of topside, and mating of topside and hull. The platform will be constructed at Aker Kvaerner Stord.

A NKr450m living-quarters contract was awarded to Leirvik Module Technology. The design envisages around 3,600m² of floor space. The quarters module will provide 100 single cabins with en suite facilities, as well as offices, a control room, a canteen and lounges. This unit is scheduled for completion by 2009, and will be built in aluminium to give a total weight of 1,500t including helideck and lifeboat station.

Samsung Heavy Industries was awarded the $150m contract to build the hull. Samsung has commenced mobilisation activities with a planned fabrication start in South Korea in February 2008. Up to 1,000 people will be working on the 14,000t hull structure.

The completed hull will then be transported to Aker Stord, south of Bergen, Norway for assembly.

OIL AND GAS PRODUCTION

Gas will be sent via the UK Flags pipeline to St Fergus in Scotland. Oil will be piped to the Troll II line and further to the Statoil-operated Mongstad refinery north of Bergen. Start-up of oil and gas production is expected in 2010.

Gaz de France will be operator during the production phase. Gjøa operations are being planned with a logistics, supply and helicopter base at Florø, north of Mongstad. Gaz de France's operations organisation will be based in Stavanger.

Statoil is development operator for Gjøa, while Gaz de France takes over as operator when the field comes on stream. The licensees are Gaz de France (30%), Petoro (30%), Statoil (20%), Shell (12%) and RWE Dea (8%).

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