press release

Chevron Press Release - Chevron, Partners Celebrate First Production From U.K.'s Britannia Field

Photo of Britannia Platform

Britannia, majestically rising nearly 440 feet above the surface, dwarfs two nearby vessels. Chevron's Alba platform can be seen in the distance.

SAN FRANCISCO, Aug 3, 1998 A major new gas condensate field has begun production, on time and nearly 20 percent under its original budget, Chevron announced today.

The Britannia field is one of the largest known remaining gas fields in the U.K. to be brought onto production. With estimated gas reserves of 3 trillion cubic feet, the field will produce enough gas to meet at least eight percent of the countrys current energy needs

Operated jointly by Chevron and Conoco on behalf of an international consortium, Britannia is located 130 miles northeast of Aberdeen in the U.K. sector of the North Sea. The field was developed with the major part of its gas production pre-sold under long-term contracts.

The Britannia project team deserves high praise, said Richard Matzke, a director of Chevron Corp. and president of Chevron Overseas Petroleum Inc. Im proud of them and of the results of their dedication and determination, particularly as they maintained an enviable safety record while bringing the project in under budget.

Matzke pointed out that the original development budget of $2.5 billion was reduced by nearly 20 percent, with actual costs now forecasted at approximately $2 billion a significant savings and a testament to the project teams cost-reducing commitment.

Through its steel platform and subsea facilities, Britannia is expected to reach its full daily capacity of 740 million standard cubic feet of gas per day, and over 50,000 barrels of condensate by Oct. 1, 1998. Gas will be transported through a new pipeline to St Fergus, Scotland; condensate will be transported via the Unity Platform into a second new pipeline connecting to the Forties Pipeline System.

Establishing and maintaining an exemplary safety record was job one, noted Robert Connon, managing director of Chevron U.K. Ltd.We congratulate the project team on bringing the field on stream with a safety performance of which our team and our industry can be proud.

Chevron U.K. Ltd., a subsidiary of San Francisco-based Chevron Corp., pioneered U.K. North Sea drilling in 1964 and is currently operator of the Alba field.

Notes to editors:

Co-venturers in the Britannia project:
Chevron UK Limited (co-operator) -- (30.20%)
Conoco (U.K.) Limited (co-operator) -- (42.41%)
Union Texas Britannia Limited -- (09.42%)
Saga Petroleum Company UK Limited -- (09.01%)
Phillips Petroleum Company UK Limited -- (06.78%)
Texaco North Sea UK Company -- (02.18%)


Britannia gas/condensate field

The Britannia gas/condensate field development is one of the largest and most significant ever undertaken in the United Kingdom. Under an agreement unique in the UK, Chevron U.K. Limited and Conoco (U. K.) Limited have established a separate company, Britannia Operator Ltd (BOL), to act as Operator of the field. Britannia will play a key role in meeting the UK's need for primary energy from indigenous sources.


  • Location: 210 kilometres north-east of Aberdeen
  • Discovered: by wells 15/30-1 and 16/26-2, drilled respectively by Venture 1 drilling rig in 1975, and Ocean Kokuei in 1977
  • Appraisal drilling: completed with the wells 16/26-24 and 15/30-10 in 1992
  • Government approval: December 1994
  • First production due: third quarter1998
  • Field life: approx. 30 years
  • Estimated recoverable reserves: approx. 3 trillion cubic feet of gas, 145 million barrels condensate and natural gas liquids (NGL)
  • Size of reservoir (areal extent): 112 sq km (70 sq miles)
  • Development wells: 35 projected
  • Peak production capacity: 740 million standard cubic feet of sales gas, and in excess of 50,000 barrels condensate per day
  • Pre-drilling: 17 wells were pre-drilled in 1995 and 1996, 7 by the rig Sovereign Explorer at the subsea manifold site and 10 by the Sedco 711 at the platform site through a pre-installed template
  • Export - Gas and gas liquids: by new 27" 186km (116 mile) pipeline, installed during 1997, to St Fergus, Scotland, for processing at the SAGE (Scottish Area Gas Evacuation) terminal
  • Export - Condensate: by new 14" 44km (27 mile) pipeline, installed during 1997, to the BP Forties Pipeline System via the Unity Platform
  • Terminal facilities: SAGE terminal expansion comprises a by-pass train which will add more than 740 million standard cubic feet of gas per day (mmscf/d) to the current 1,150 mmscf/d capacity of the terminal's two existing process trains.
  • Development budget: 1.55 billion. Forecasted expenditures are about 1.25 billion in total.
  • Water depth: 146m
  • Gas purchasers: include Conoco (U.K.) Limited, Mobil Gas Marketing (UK) Limited, National Power plc, PowerGen plc and Total Oil Marine plc.
Conoco (U.K.) Limited 42.41%
Chevron U.K. Limited 30.20%
Union Texas Britannia Limited 9.42%
Saga Petroleum UK Limited 9.01%
Phillips Petroleum Company United Kingdom Limited 6.78%
Texaco North Sea UK Company 2.18%
Detailed engineering  
Topsides began August 1994
Subsea began September 1994
Steel jacket began October 1994
Export pipeline began July 1995
Pre-drilling programme began May 1995
Topsides fabrication began August 1995
Jacket fabrication began August 1995
Subsea manifold fabrication began April 1996
Installation of manifold 12 April 1997
Installation of jacket August 1997
Installation of topsides August 1997
Installation of flowlines & umbilical July 1997
Installation of export pipelines July 1997
Hook-up and commissioning of facilities October 1997 - Summer 1998
Facility completion 31 July 1998
Platform drilling Begins second quarter 1998
First production 3rd quarter1998
PLATFORM Drilling, production and accommodation platform located at the east end of the reservoir in Block 16/26
Total operating weight 28,900 tonnes
Total dry weight 19,400 tonnes
Overall deck dimensions 90 x 40 x 20 m high
Height from flare tip to seabed 268 m
Design flowrate (gas) 814 MMSCFD
Design flowrate (condensate) 70 MBPD
Number of well slots 36
Accommodation 140 persons (max)
Design and management services AMEC Process and Energy, London
Drilling design KCA Ltd, Aberdeen
Accommodation module fabrication SLP, Lowestoft
Drilling facilities module fabrication SLP, Teesside
Integrated deck and flare boom fabrication Kvaerner Oil & Gas, Teesside
Piperack and compression module SLP, Teesside
Jacket and topsides installation Heeremac, Leiden, Holland
Control system Silvertech, Horsham
Offshore hook-up and commissioning AMEC Process & Energy, Aberdeen
Substructure 8-legged steel jacket over 10 slot pre-drill template
Jacket design Kvaerner John Brown Engineering, London
Jacket fabrication Dragados Offshore Services, Cadiz, Spain
Substructure Dimensions 78m x 70m (base) x 158m high
Substructure Weight 20,000 tonnes
Piles 20 x 2.74m diameter, 5 at each corner; vertical skirt piles driven to 105 m penetration; total weight approx 12,000 tonnes
Piles construction SIF Holland Offshore, Roermond, The Netherlands
Risers 2 export risers (1 x gas, 1 x condensate); 5 infield risers; 5 umbilical J-tubes, provision for 4 retrofitted caissons for future tie-ins
Subsea Production Facilities

700 tonne subsea manifold with 14 slots (8 wells pre-drilled, 3 planned future, 3 spare) located 15km from the platform in Block 15/30

Heated flowline bundle to platform (37" carrier, 14" dia. Production, 8" dia. Test, 3" methanol, 12" water return)

Remote control from platform via 2 electro-hydraulic umbilicals

Provisions for Future Expansion Allows for possible tie-in of a remote satellite well cluster from the west and planned future tie-in of up to four well satellite template located mid-line
Design and manufacture of subsea well systems Dril-Quip, Aberdeen
Design, fabrication, installation and tie-in of subsea pipeline bundles Smit Land & Marine/Stolt Comex Seaway Alliance, Brombrough/Aberdeen/Tain
Subsea production control system ABB Seatec, Nailsea, Bristol
Fabrication of subsea manifold Consafe, Burntisland
Manifold installation Heeremac, Leiden
Design and engineering of export pipelines JP Kenny, Staines, Middlesex
Installation of pipelines EMC, Motspur Park, Surrey
Gas export linepipe supply Europipe GMbH, Germany

Updated: August 1998