Second Western Area Well Success Completes Cygnus Field Appraisal

Centrica plc today announced the successful drilling of a second appraisal well (44/12a-5) in the western region of the Cygnus gas field, located in the UK southern North Sea. This latest well completes the full appraisal of the field within its current field boundary and follows the successful appraisal in March of the first western area well (44/11a-4).

This second appraisal well has achieved a stabilised flow rate of 29 million standard cubic feet per day (MMscfpd), confirming good reservoir characteristics. Analysis from discovery wells together with six appraisal wells and 3D seismic evaluations will allow the reserves potential of the field to be assessed as part of full field development planning.

Centrica owns a 48.75% equity stake in the Cygnus field along with operators GDF SUEZ E&P UK Ltd and licence participant Endeavour Energy UK Limited.

Following the successful appraisal of the eastern area of Cygnus in 2009, the licence partners are pursuing a revised and optimised field development plan. This comprises a two-phase approach with an enlarged first phase to include the full development of the eastern area, and a phase two development of the western area. The development schedule is being reviewed by the partners as part of the ongoing field development evaluation with first gas from eastern area scheduled for 2013.

The Cygnus field partners have also been awarded exploration licence P1731 by the Department of Energy and Climate change (DECC) which surrounds the Cygnus field and could extend it further.

Centrica Energy’s Upstream Managing Director, Jonathan Roger, said: “This is potentially one of the most significant undeveloped gas fields in the UK continental shelf and comes at a time when developing the untapped potential of the North Sea is critical to UK energy supply security. We are now working closely with our partners to commence the first phase of development.”