Clair Phase 1

Clair Phase 1 Oil and Gas Field Profile

Location and Geography

• The Clair Phase 1 Oil and Gas Field is located approximately 75 kilometers west of the Shetland Islands in the North Sea, United Kingdom.
• It is situated in water depths of up to 150 meters and spans an area of about 220 square kilometers, covering five licence blocks (206/7a, 206/12, 206/8, 206/13a, and 206/9).

Discovery and Development History

• The Clair field was originally discovered in 1977 and is the UK’s largest hydrocarbon resource.
• Between 1977 and 1995, several appraisal wells were drilled to delineate the field. A 3D seismic survey was also conducted during this period.
• The first development phase (Clair Phase 1) was sanctioned in 2001, representing an investment of £650 million by BP and its partners.

Project Details

Operator and Ownership:

• The operator of the Clair Phase 1 field is BP Exploration Operating Company.
• The ownership is shared among BP (45.1%), Shell UK Limited (28.0%), ConocoPhillips (7.5%), and Ithaca Energy (19.4%).

Production Start:

• Production from the Clair Phase 1 field commenced in February 2005, with initial production through the original appraisal well. Full production built up to a plateau of 50,000 barrels per day (bpd) by 2007.

Reserves and Production:

• The Clair Phase 1 field has estimated recoverable oil reserves of 300 million barrels as of 2018. The initial hydrocarbons in place were estimated at 7 billion barrels of oil equivalent across the entire Clair field.
• The field produces approximately 12.26 million barrels of oil per year and 120.68 million cubic meters of gas per year as of 2019.

Infrastructure:

• The field is developed using a conventional steel platform supported by a four-legged, lattice-type braced jacket. The jacket is approximately 165 meters in height and is positioned over the existing 206/8-10z well.
• The topsides facilities include three deck levels (main, production, and cellar) housing all facilities for drilling and processing of produced fluids and gas. Key modules include the well manifold system, well test system, two-train separation, oil export system, gas compression, and produced water handling.

Export:

• Oil from the field is exported to the Sullom Voe Terminal in Shetland via a 105km, 22-inch diameter pipeline. Produced gas is exported through a 10km, 6-inch diameter spur line into the Magnus enhanced oil recovery trunkline.

Geology

• The reservoir consists of heavily faulted and fractured Devonian to Carboniferous age sandstones. The field is divided into nine fault-bounded segments with a common free water level and a maximum oil column of around 600 meters. A gas cap is present in the structurally elevated ridge segments.

Contractors and Engineering

• Major contracts were awarded to several companies:
  • Aker Verdal: Fabrication of the platform jacket.
  • AMEC: Fabrication and integration of the deck, and engineering and project management services.
  • Heerema Hartlepool: Fabrication of the drill rig.
  • Mustang Engineering: Front-end engineering, detail design, and project management for the platform.
  • Saipem: Installation of the platform.

Future Development

• The Clair Phase 1 facilities are expected to continue production until 2028. The Clair Ridge Project, which is the second-phase development, aims to extend the life of the field to 2050 and increase the overall recovery from the Clair field.