Alvheim

Location and Geology

The Alvheim oil field is located in the central part of the North Sea, close to the British sector, on the Norwegian Continental Shelf. It is situated in blocks 24/6P (PL 203), 24/6P (PL 088 BS), 25/4P (PL 036 C), and 25/4P (PL 203), with a water depth of approximately 122 meters (407 feet).

The field's reservoir is of Paleocene age, consisting of Heimdal formation sandstones concentrated as submarine fan deposits at a depth of about 2,200 meters.

Discovery and Development

The Alvheim field was discovered in 1998 through the well 24/6-2, which tested the hydrocarbons potential of the A2 North Heimdal T60 sand prospect within the Lista Formation. The well was drilled by the semi-submersible rig Transocean Leader and reached a total depth of 2,722 meters.

The field was developed in two phases. The first phase involved ten production wells and two water disposal wells, with first oil achieved in June 2008. Phase II began in 2009 and included the drilling of three multilateral wells, completed in September 2012. There are also plans for further phases, including Phase III.

Reserves and Production

The Alvheim field contains recoverable reserves of approximately 180 million gross barrels of oil equivalent. When combined with the nearby Vilje field, the total resources are estimated to be between 200 and 250 million barrels of oil equivalent gross.

As of the latest data, the Alvheim conventional oil field has recovered about 92.44% of its total recoverable reserves, with peak production in 2009. Production is expected to continue until the field reaches its economic limit in 2029.

Field Operations and Infrastructure

The Alvheim field is operated by Aker BP, with ConocoPhillips also holding a stake in the field.

The field is developed using the Alvheim FPSO (Floating Production, Storage, and Offloading) facility, which was converted from the multipurpose shuttle tanker Odin. The FPSO has an overall length of 252.16 meters, a moulded breadth of 42 meters, and a moulded depth of 23.2 meters. It has a storage capacity of 560,000 barrels of oil and is passively moored by 12 lines designed to withstand a 100-year storm.

Gas from the field is exported through the UK SAGE system via a 14-inch, 24-mile cross-border pipeline to the St. Fergus gas terminal in Scotland. Produced water is reinjected into the reservoir.

Satellite Fields and Expansions

The Alvheim area includes several satellite fields tied back to the Alvheim FPSO, such as:

• Vilje: Started production in August 2008.
• Volund: Started production in April 2010.
• Bøyla: Developed as a subsea tie-back to the Alvheim FPSO, producing since January 2015.
• Skogul: Tied-in to Alvheim and started production in 2020.
• Frosk: Discovered in January 2018, with first oil in 2023. The field has estimated recoverable reserves of ten million barrels of oil equivalent and is expected to produce for ten years.

Aker BP is also maturing other discoveries in the area, including:

• Kobra East & Gekko (KEG): Drilling started in January 2023, with production expected early next year.
• Tyrving (ex-Trell and Trine): Fabrication underway, with drilling of three wells to begin in the first half of 2024 and production starting the following year.

Increased Oil Recovery (IOR) and Life Extension

Aker BP is focused on increasing oil recovery (IOR) at Alvheim. The company is undertaking various projects to debottleneck the FPSO, improve capacity, and facilitate the tie-in of more discoveries. This includes a water capacity upgrade project sanctioned in the fourth quarter of 2020 and a gas debottlenecking project to increase the FPSO’s gas production capacity by 15%.

Efforts to extend the lifespan of the Alvheim FPSO are ongoing, including upgrades such as the turbine generator control system.

Production Goals and Future Plans

Aker BP aims to produce more than one billion barrels from the Alvheim FPSO through the development of several satellite fields. The company continues to work on maturing new discoveries and expanding the existing infrastructure to support additional tie-backs to the Alvheim FPSO.

Expansion projects, such as the Kameleon Gas Cap Blow Down and the Kobra East & Gekko (KEG) Phase 2, are currently in the feasibility stage, targeting start-up between 2030 and 2034.