The Johan Castberg project comprises three oil fields, namely Johan Castberg (formerly Skrugard), Havis, and Drivis, located in production license PL 532, about 100km northwest of the Snøhvit-field in the Barents Sea, offshore Norway.
Ownership of production licence PL532 is held by Equinor (50%), Vår Energi (30%) and Petoro (20%).
The oil fields are located at water depths of approximately 360m to 390m. The reservoirs extend to depths of 1,900m and are expected to hold 400 to 650 million barrels of proven oil reserves.
The Johan Castberg project is operated by Equinor (formerly Statoil). Equinor submitted the project’s plan for development and operation (PDO) in December 2017, while the project received approval from the Norwegian Government in June 2018. Construction of the Johan Castberg project’s topside began in November 2018, while first oil from the field is expected to flow in 2022.
Estimated to cost approximately NOK 49bn ($8.01bn), the project will generate employment for approximately 4,800 people during the construction period.
The field’s production capacity is expected to be 200,000 barrels of oil equivalent per day over an estimated operational life of 30 years.
Discovery, drilling, and development of the Johan Castberg project
Johan Castberg was discovered in April 2011 and Havis in January 2012, while Drivis was discovered in May 2014. The fields are situated in blocks 7219/9 and 7220/4,5,7. The project lies 150km northwest of Goliat and roughly 240km from Melkøya.
The fields were discovered after the 20th licensing round on the Norwegian Continental Shelf was announced in April 2009 by the Ministry of Petroleum and Energy.
Drilling of Johan Castberg was concluded in early 2011 with the completion of drilling the well (7220/8-1) using Transocean’s rig Polar Pioneer, which encountered hydrocarbons at approximately 1,250m below sea level.
Drilling of the Havis prospect concluded in early 2012. The last well, 7220/7-1 was drilled using Aker Solution’s rig, Aker Barents. The well was drilled to a depth of 2,200m below sea level and at sea depth of 365m. Estimated volumes from Havis are expected to be between 200 and 300 million barrels of recoverable oil equivalent.
The appraisal of the Skrugard (now known as Johan Castberg) discovery was concluded in March 2012. Appraisal well 7220/5-1 was drilled using the Transocean Barents drilling rig to a depth of 1,740m below sea level, at a water depth of 388m. The appraisal confirmed the estimated initial volume from the Skrugard, and Havis facilities in the range of 400 to 650 million barrels of recoverable oil.
Equinor is also drilling exploration wells around the Johan Castberg area to further increase the resources to make the project more robust. The company discovered the Skruis exploration, adding to Johan Castberg’s recoverable reserves in October 2018.
Development of the Norwegian oil fields
The development concept for the first two discoveries was announced in February 2013. The plan includes installation of a floating production unit (FPU/FPSO) with a pipeline to shore and an onshore oil terminal at Veidnes, outside Honningsvag, in Finnmark.
Fields will share common infrastructure facilities such as the subsea system, comprising umbilicals, subsea trees, wellheads and flowlines, along with the topside installed with modules for gas injection, re-compression, and separation.
The 1,900t FPSO vessel will be equipped with two gas turbine generators, water and chemical injection modules, flare system besides being capable of accommodating 140 workers.
Production from the fields will be tied-in to a semi-submersible floating installation through a subsea production system located in about 380m of water.
A total of 18 production wells will be drilled, in addition to 12 water and gas injection wells to provide pressure support.
Transportation of the produced oil from offshore to the onshore oil storage facility will be facilitated by a pipeline measuring 280km in length.
The oil will be stored in two mountain caverns. It will be transferred to the quay through a pipeline. Crude tankers will further transport the oil from the terminal.
Contractors for the Johan Castberg Field Development project
IKM Ocean Design conducted the pre-front end engineering design (FEED) for the project.
Sevan Marine received a contract in March 2012 to carry out a concept study for utilising an FPSO for development of the Johan Castberg field. The company was also involved in the feasibility study that was conducted for the project earlier in 2011.
Aker Solutions carried out the preliminary studies for the development of the first two discoveries in addition to supplying subsea production system and designing the FPSO.
Kvaerner received the contract for the delivery of topside modules along their hook-up and integration in February 2018. Sembcorp Marine together with Aker Solutions carried out designing of the FPSO’s accommodation unit and its modules.
Other contractors involved in the Johan Castberg project are ABB, SUEZ, Subsea 7, Siemens, PALFINGER MARINE, Baker Hughes, Multiconsult, Jotron, Kongsberg Oil & Gas Technologies, Energomontaż-Północ Gdynia, ProSep, KOSO Kent Introl, Glamox, Alcatel Submarine Networks, Ocean Installer, Vissim, Hummervoll Industribeleg, AF AeronMollier, and MRC Global.
Goliat Oil and Gas Field, Barents Sea, Norway
The Goliat field is located in the production licence 229, in the Barents Sea, north of Russia and Norway.
Johan Sverdrup Field, North Sea, Norway
Johan Sverdrup field consists of two discoveries, Avaldsnes and Aldous, located off the coast of Stavanger in the Norwegian North Sea.