World’s longest ETH pipeline installed at Fenja field

Neptune Energy has completed the installation and testing of the electrically trace-heated (ETH) subsea production pipeline at its Fenja field in the Norwegian sea.

Said to be the world’s longest, the 37-kilometre ETH will transport oil from the Fenja field to the Njord A platform, operated by Equinor.

TechnipFMC’s vessel carried out the offshore installation across two subsea campaigns in 2020 and 2021 approximately 120 kilometres north of Kristiansund at a water depth of about 320 metres. The company also fabricated and assembled the ETH pipe.

“Completing the installation and testing of the ETH pipe is a great technical achievement and a major step forward in the development of the Fenja field”, said Erik Oppedal, Neptune’s director of Projects and Engineering in Norway.

“The ETH pipe-in-pipe solution is crucial for extracting the oil and is a creative, cost-effective approach that permitted us to tie the field back to existing infrastructure”.

Due to the high wax content of the Fenja field’s oil, the contents of the pipeline must be warmed to a temperature above 28 degrees Celsius before starting the flow after a scheduled shutdown or interruption.

During normal production, the temperature in the pipeline would be well above this temperature, Neptune explained.

Ståle Ryggvik, TechnipFMC’s project director, said: “The successful completion of the Fenja ETH pipe-in-pipe installation has been made possible through our unique iEPCI project capabilities, close collaboration with Neptune Energy, and by leveraging TechnipFMC’s extensive experience in the technology”.

Fenja is Neptune’s first operated development project on the Norwegian Shelf and is estimated to contain 97 million boe.

Neptune kicked off its Fenja drilling campaign following the spud of the first well in April 2020. In September 2020, the company started drilling the Bue well on the field. Bue is, along with Pil, one of the discoveries on the Fenja field.

According to the company’s project update, drilling of the Fenja production wells is scheduled to begin in the fourth quarter of 2021, by the Deepsea Yantai drilling rig.