Engie’s Cygnus field has achieved first gas and is on course this year to become the largest producing gas field in the United Kingdom North Sea. Discovered in 1988, Cygnus went into development only after the government introduced a GBP 500-million (USD 810-million) tax allowance for large shallow-water gas fields in July 2012. Located 90 miles offshore Lincolnshire, England, the field has estimated gross 2P reserves of approximately 635 Bcf. Engie has a 38.75% interest in Cygnus with the remaining stakes held by Centrica (48.75%) and Bayerngas (12.5%).