Field/project development

Norway Greenlights Subsea Tiebacks To Extend Mature Field Production

The Irpa gas field, Verdande oil field, and Andvare production-well tiebacks will extend the lives of the mature Aasta Hansteen and Norne fields into the late 2030s.

Aasta Hansteen
Underwater illustration of the Aasta Hansteen FPSO.
Source: Equinor

Norwegian authorities have approved the development and operation plans for two subsea fields in the Norwegian Sea—the Irpa gas field and the Verdande oil field—along with the production well Andvare in the Tampen area.

The approvals are the latest in a string of announcements as Norway’s strategy unfolds to explore near-mature fields to develop production cost-effectively using existing infrastructure, thus securing its position as oil and gas supplier of choice for Europe and the UK into the late 2030s.

Expected on stream in 2026, Irpa will be tied back to the floating production, storage, and offloading facility (FPSO) at the Aasta Hansteen field—the first spar platform on the Norwegian Continental Shelf and the world’s largest at a height exceeding the Eiffel Tower.

The Verdande oil field and the Andvare well will be tied back to the Norne field and FPSO with the intention of extending the life of Norne, which has been in production since 1997. Equinor expects the Verdande field to begin producing in Q4 2025.

The Andvare well will be drilled as a sidetrack from one of 15 existing subsea templates (including 52 production and injection wells) on the Norne field, Equinor said.

“By utilizing the Aasta Hansteen and Norne infrastructures, these development projects will quickly bring new production to market with low development costs, while extending the activity on the host platforms," Equinor's Senior Vice President for Project Development Trond Bokn said in a news release.

Deepest Drilling Yet on the Norwegian Shelf

Equinor Energy AS operates the $1.38 billion Irpa project with a 51% interest. Minority partners include Wintershall DEA (19%), Norway’s state-owned Petoro (20%), and Shell (10%). The Aasta Hansteen field is located at a depth of 1300 m in the Vøring area in the Norwegian Sea, 300 km west of Sandnessjøen.

Irpa will be developed with three wells drilled at depths of up to 1350 m, making it the deepest field drilled on the Norwegian Continental Shelf. Once connected to an 80-km pipeline to the Aasta Hansteen platform, Irpa will contribute to extending Aasta Hansteen’s life to 2039, according to Equinor.

Recoverable gas reserves are estimated at 20 billion std m3, as well as 0.4 million std m3 in condensates, or approximately 124 million BOE.

On 30 June, the Norwegian Petroleum Directorate (NPD) reported that 12 wildcat wells were completed in the first 5 months of 2023 out of a total of 18 exploration wells drilled; discoveries were confirmed in seven wells. By year-end, NPD expects to have drilled a total of 40 wildcat and appraisal wells.

“Most of the wells are being drilled near infrastructure, which could yield valuable additional resources for existing fields,” Director General Torgeir Stordal said in a news release, adding that some wells are being drilled “in less-explored areas.”

The discoveries total between 9 and 32 million std m3 oil equivalent, according to NPD.

In May, Norway reopened Equinor’s Njord field in the Norwegian North Sea after 6 years of extensive upgrades to the platform and floating storage and offloading vessel aiming to double both field life and production.