Troll Nord partners secured consent from Norwegian authorities to start up facilities and modifications associated with the North Sea Troll Phase 3 project. The Equinor Energy AS-operated development was originally scheduled to come on stream this spring but was postponed due to COVID-19 restrictions.
The plan for development and operation (PDO) for Troll Phase 3 was approved in December 2018 (OGJ Online, Dec. 7, 2018). The project is further development of Troll field and will produce gas from Troll Vest.
Development comprises two subsea templates with eight gas wells tied into the Troll A platform. The wellstream is routed to Troll A through a new 36-inch pipeline for further compression and export via existing infrastructure.
Recoverable reserves from Troll Phase 3, mainly gas, are estimated at 2.2 billion boe.
With an 8-billion kroner investment in Troll Phase 3, licensees expect production from the development to last at least 30 years.
Troll was proven in 1979, and the original PDO was approved in 1986. The plan was updated in 1990 in order to move the gas processing to the Kollsnes terminal. The field came on stream in 1995.
Phased development
Troll, which supplies as much as 7% of Europe’s daily demand for gas, was developed in phases, with gas extraction from Troll Øst in Phase 1 and oil from Troll Vest in Phase 2. Troll Phase 1 was developed with Troll A, which is a fixed foundation wellhead and compression installation with a concrete substructure. Troll A receives power from shore. Gas compression capacity was expanded on Troll A in 2004-2005 and again in 2015.
Troll Phase 2 was developed with Troll B, which is a floating living quarters and production facility in concrete, and Troll C, which is a semisubmersible living quarters and production facility in steel.
The oil in Troll Vest is produced from multiple subsea templates tied into Troll B and Troll C via pipelines. Production from the Troll C installation started in 1999. Troll C is also used for production from Fram, Fram H-Nord, and Byrding. Several amended development plans were approved in connection with installing multiple subsea templates on Troll Vest.