Equinor Energy AS and partners will invest about NOK 4 billion ($410 million) in the new Troll West increased gas recovery north (TWIN) subsea development in Troll field in the North Sea.

The TWIN project consists of two wells in a template and a pipeline connected to existing subsea infrastructure. The umbilical and monoethylene glycol line will be extended to the new development.

The project is expected to contribute about 11 billion std cu m of gas to Troll. It is the third step of Troll Phase 3, which produces gas from the Troll West reservoir. Recoverable reserves from Troll Phase 3, mainly gas, are estimated at 2.2 billion boe.

In accordance with the Petroleum Act, the partnership will now send an announcement to the Ministry of Energy concerning the development. An environmental impact assessment has been carried out.

Troll, which supplies as much as 10% of Europe’s daily demand for gas, contains about 40% of the total gas reserves on the Norwegian continental shelf and was developed in phases, with gas extraction from Troll Øst in Phase 1 and oil from Troll West in Phase 2.

The oil in Troll West 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 West.

Equinor Energy AS is operator of TWIN (30.55%) with partners Petoro AS (55.93%), A/S Norske Shell (8.19%), TotalEnergies EP Norge AS (3.69%), and ConocoPhillips Skandinavia AS (1.64%).