Concept Selection Study

Project Overview

The Frigg Gamma and Frigg Delta discoveries are located in the Norwegian sector of the North Sea within PL442 east of the closed Frigg Main field. Gamma and Delta, which lie in PL442, have a recoverable reserve estimate of 16.04 MSm3 of oil with an API gravity of 22.5-25°.

Centrica Energi has been evaluating the development options for the Frigg Gamma Delta (FGD) field, includingevelopment on a standalone basis or in a combined development with other nearby fields. The Select Study fixed platform solution scope has been part of this evaluation. CONSUB provided all subsea input to thestudy which was coordinated by g3 Baxi Partnership Ltd. d

Scope of Services

CONSUB’s supported an early phase scope to select the optimum drilling option and subsea well arrangement. This was part of other early phase scopes which supported and refined the fixed platform solution for this Select study (wells drilled at a Delta drill centre tied back using subsea facilities to a fixed production platform at the Gamma drill centre with stabilized oil exported to Oseberg A via a newly installed pipeline).

CONSUB provided the conceptual design of the subsea facilities. The subsea pipeline design included:

• Routing assessment;
• Material selection;
• Mechanical design including stability, expansion and buckling assessment;
• Pipeline coating and corrosion protection design;
• Crossing design and quantity;
• Trenching lengths and rock dump volumes;
• Installation assessment.

The subsea production system design included:

• Definition of the control system and umbilical
• Comparison of standard SPS supplier solutions and their applicability to FGD
• Compare diver or diverless tie-in systems.

The definition derived through the conceptual design was used to support a Class III cost estimate and associated project execution schedule which was integrated into the overall fixed platform solution CAPEX.