Gina Krog

Location and Geology

The Gina Krog oil and gas field is located in the central part of the North Sea, approximately 230 kilometers southwest of Stavanger, Norway, and about 30 kilometers northwest of the Sleipner field. It is situated on the Utsira High, specifically in blocks 15/5 and 15/6 of production licences PL 303, 048, 029, and 029B. The water depth at the site is around 120 meters.

The hydrocarbons at Gina Krog are extracted from sandstone reservoirs of Middle Jurassic age in the Hugin Formation, at depths ranging from 3,300 to 3,900 meters. The reservoirs are structurally complex, segmented, and vary in thickness and quality. They are capped by Heather shales and have a coal layer at the base on top of the Sleipner Formation.

Discovery and Development History

The Gina Krog field was first discovered in 1974 under the name Dagny. Initially, it was considered a small gas field. However, after further exploration and appraisal between 2008 and 2011, significant volumes of oil were identified, and the field was renamed Gina Krog in 2013. The plan for development and operation (PDO) was approved in 2013, and production commenced in June 2017.

Ownership and Partners

The Gina Krog field is operated by Equinor, which holds a 58.7% interest. The other partners are KUFPEC Norway with a 30% interest and PGNiG Upstream Norway with an 11.3% interest.

Infrastructure and Production

The field is developed using a standalone, 20-well, 70-bed jacket platform with a designed production capacity of 10,000 Sm³/d of oil and 9,000,000 Sm³/d of gas. The platform includes living quarters and processing facilities. Initially, the field was produced using gas injection in most reservoir segments, but since 2021, all segments have been produced via pressure depletion.

Stabilized oil is stored in the Randgrid Floating Storage and Offloading (FSO) unit, which was converted from a shuttle tanker, and then shipped to refineries by shuttle tankers. Rich gas is processed at the Sleipner A platform, while condensate is transported via the Sleipner R platform and then processed at Kårstø into natural gas liquids (NGL) products. Sales gas is exported from Sleipner A via Gassled (Area D) to the UK and EU markets.

Recent Developments and Future Plans

In 2023, Equinor made a commercially viable gas discovery near the Gina Krog field, with plans to start production in the fourth quarter of 2023. This discovery is expected to help extend the lifetime of Gina Krog and strengthen its profitability due to the use of existing infrastructure.

Additionally, Equinor has plans to develop the Eirin gas field, discovered in 1978, as a subsea facility tied back to the Gina Krog platform. This development is expected to extend Gina Krog’s productive life from 2029 to 2036 and will contribute to low CO₂ emissions from production. The Eirin field has estimated recoverable reserves of 27.6 million barrels of oil equivalent, mostly gas, and production is expected to start as early as 2025.

A new 23km long pipeline between Gina Krog and Sleipner A is set to replace the existing Rangfrid FSO in 2024, aiming to reduce annual operating costs and carbon dioxide emissions by around 18,000 tonnes per year.

Environmental and Operational Efficiencies

Since September 2023, the Gina Krog field has been fully electrified by power from shore via the Johan Sverdrup field, which significantly reduces its carbon footprint. The field's operations, including the upcoming Eirin development, are designed to have low CO₂ emissions, with only about three kilos of CO₂ per barrel of oil equivalents.

Investments and Production Levels

The development of the Gina Krog field involved an investment of around NOK 31 billion ($3.7 billion). In 2019, the net production from Gina Krog averaged 1.8 thousand barrels of oil equivalent per day (mboepd). The field is expected to host 225 million barrels of oil and gas reserves.

Contractors and Service Providers

Several contractors and service providers have been involved in the development of the Gina Krog field, including:

• Heerema Fabrication Group for the jacket
• Daewoo Shipbuilding & Marine Engineering (DSME) for the design and construction of the topsides
• Aker Solutions for detailed engineering services and offshore hook-up and commissioning
• Teekay for the conversion of the FSO
• Ocean Installer for subsea installations
• SNC-Lavalin for detailed design of the jacket
• DOF Subsea for turret mooring and riser installation
• GE for turbomachinery equipment and services
• ABB for internal and external telecommunication systems.