The last of four main structures for Cygnus natural gas field has departed the Heerema Hartlepool yard in the UK en route to installation on North Sea Blocks 44/11a and 44/12a, 150 km offshore Lincolnshire (OGJ Online, Aug. 13, 2012).
It’s the Cygnus Alpha compression module, which will be set atop the Alpha process and utilities topside. That unit, the largest of four platforms due on the field, departed the yard earlier with the Bravo wellhead platform.
The Cygnus Alpha wellhead platform sailed away in May. The field also will have a quarters platform, which, like the Alpha wellhead platform, will be bridge-linked to the process and utilities platform.
The unmanned Bravo wellhead platform will be tied to the process and utilities platform with a 7.5-km, 12-in. production line and umbilicals. Production is to begin by yearend.
Operator GDF Suez E&P UK Ltd. plans to produce from five wells drilled from each of the wellhead platforms. Production will peak at about 250 MMcfd of gas. The total of proved and probable reserves is estimated at 635 bcf.
Cygnus gas will flow through a new 51-km export line linked to the Esmond Transport System pipeline, which makes landfall at Bacton.