Equinor and its partners in the Åsgard and Mikkel licences have initiated phase 2 of the Åsgard subsea compression project in the Norwegian Sea. The development aims to maintain production levels from the field by increasing pressure in the pipelines connecting the wells to the Åsgard B platform.
Next-Generation Technology Enhances Resource Recovery
Trond Bokn, Equinor’s senior vice president for project development, emphasised the technological advancement: “In this project, Equinor, together with partners and suppliers, has further developed and qualified the next generation of compressor modules. The technology allows us to recover more gas from producing fields. Good resource utilisation is important to maintain high and stable production from the Norwegian continental shelf.”
Left:Trond Bokn, Equinor’s senior vice president for project development.Photo credit: Arne Reidar Mortensen. Right :Randi Hugdahl, vice president for exploration and production for Åsgard and Kristin Photo credit: Ole Jørgen Bratland
The project builds upon extensive field history. The original plan for development and operation (PDO) of Åsgard received approval in 1996, with Åsgard A commencing production in 1999 and Åsgard B following in 2000. The PDO for Åsgard subsea compression gained regulatory approval in 2012, and phase one of the compression system began operations in 2015, marking the world’s first facility for gas compression on the seabed.
Phase 2 Installation Completed
The initial development plans recognised the long-term need for increased pressure to compensate for reservoir pressure decline. The first compressor module in phase two underwent replacement in 2023, with the second and final module now installed at a depth of 270 metres, completing the phase 2 deployment.
Randi Hugdahl, vice president for exploration and production for Åsgard and Kristin, highlighted the system’s performance: “The compressor system has produced stably for ten years with almost 100 percent uptime. The system has so far contributed to increased value creation from the field of about NOK 175 billion.”
Significant Recovery Rate Improvements
Combined across both compression phases, the recovery rate from the Mikkel and Midgard fields will increase to 90 percent due to the compressor installation. This enhanced recovery represents an additional 306 million barrels of oil equivalent from the fields, demonstrating substantial resource optimisation benefits.
Technical Specifications and Infrastructure
The ÅSC station, positioned in 270 metres of water on the Midgard field approximately 40 kilometres from the Åsgard field centre, represents an impressive subsea engineering achievement. With a total weight of 5,100 tonnes, a footprint of 3,300 square metres, and extending 26 metres above the seabed, it stands as the largest subsea processing plant ever installed.
The station comprises two identical compressor trains operating in parallel, each powered by a compressor with an electric motor capacity of 11.5 MW. A complete spare train is maintained in Kristiansund, enabling rapid component replacement if operational issues occur. The system employs a modular design concept, facilitating maintenance and component exchange.
Several key components from the original compression modules have been overhauled and reused in the new modules, demonstrating a commitment to sustainable resource utilisation in the project’s execution.
Partnership Structure
The Åsgard licence partners include Equinor Energy AS (operator) with 35.01 percent, Petoro AS with 34.53 percent, Vår Energi ASA with 22.65 percent, and TotalEnergies EP Norge AS with 7.81 percent.
The Mikkel licence partners comprise Equinor Energy AS (operator) with 43.97 percent, Vår Energi ASA with 48.38 percent, and Repsol Norge AS with 7.65 percent.
The phase 2 completion represents continued technological leadership in subsea compression technology while supporting the Norwegian continental shelf’s production sustainability through enhanced recovery from mature fields.
For more information visit www.equinor.com
