Neptune Energy has recently set up four enhanced horizontal subsea tree systems (EHXT) for the Duva subsea tie-back development project in the Norwegian sector of the North Sea in a standalone operation with a vessel.
Being the first for Neptune Energy, the installation was carried by Solstad’s vessel Far Samson instead of a rig, reducing installation time, costs and operational emissions, the company said.
Thor Løvoll, Neptune Energy’s director of Drilling & Wells in Norway, said: “By introducing the latest available technology combined with quality planning and teamwork, we completed the installation safely, successfully and ahead of schedule. Deploying the subsea trees from a vessel saved about 20 days of rig time, reducing costs, time and emissions.”
Neptune said that the 20 days of reduced rig time is equivalent to approximately $12 million savings for the license partners. By using a vessel instead of a rig, installation activities saw emissions drop by more than 60 per cent.
The operation took place in cooperation with TechnipFMC, Ross Offshore, Solstad Offshore, Oceaneering, Fugro, IKM and Tigmek.
Neptune Energy’s Head of Gjøa Subsea Development, Crawford Brown, also said: “We are progressing with the Duva project at pace and have reached an important milestone. The efficient installation of the subsea trees allows the project more schedule flexibility as we enter the drilling and completion campaign for the Duva production wells.”
The drilling rig Deepsea Yantai, operated by Odfjell Drilling, will drill and complete the remaining sections of the Duva well program during Q2/Q3 2021.
The Duva oil and gas field was Neptune’s first discovery in the Norwegian North Sea. It is located 14 kilometres northeast of the Neptune-operated Gjøa field, at a water depth of 360 metres.
First production from Duva should kick off in the third quarter of 2021.
Licence partners on Duva in addition to Neptune as operator include Idemitsu (30 per cent), PGNiG Upstream Norway (30 per cent) and Sval Energi (10 per cent).