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Contract to Subsea 7 for underwater installations on Troll

May 15, 2007, 15:55 CEST

Hydro has on behalf of the Troll Oil license awarded a contract worth approximately NOK 370 million to Subsea 7 subsea for the sea lines to the Troll O2 field in the North Sea.

The deliveries comprise two flexible flowlines and one umbilical, approximately 4 kilometers each. The lines will be installed between existing Troll O1 and the new Troll O2 in 2009.

Hydro is the operator of Troll Oil and has drilled 113 production wells into the Troll field. The experience has contributed to extensive knowledge about the reservoir and its production characteristics. New data from the wells show that the recovery rate from the northwestern part of the field can be increased by drilling new production wells.

The new subsea construction effort, called Troll O2, allows the drilling of new wells with several production extensions. A well slot is also being included to accommodate the drilling of production wells into the Brent formation, where oil was proven in 2005.

The new well template will be tied into the Troll C production platform in the North Sea. It is anticipated that the new wells, which can be drilled from the template, will increase the area’s oil reserves by more than 20 million barrels.

As operator of Troll Oil, Hydro has been responsible for long-term development in the field’s thin oil zones. The field’s commercial oil reserves have increased from zero in 1986 to some 1,400 million barrels. Hydro is working on a new long-term plan for increased oil recovery from Troll. The goal is to boost reserves by 30 percent, to more than 2 billion barrels of oil.

Troll Oil includes blocks 31/2, 31/3 and 31/5 and is some 80 kilometers northwest of Bergen. The field is developed with two production platforms, Troll B and Troll C, and subsea production systems. Three drilling rigs will drill the production wells from the subsea well templates.

License holders in Troll Oil

  • Hydro (operator) – 9.78 %
  • Statoil – 20.81 %
  • Petoro – 56.00 %
  • Shell – 8.10 %
  • Total – 3.69 %
  • ConocoPhillips – 1.62 %