Fact box – Trell and Trine

25/5-9 (Trell) and 25/4-2 (Trine) are two small discoveries in the central part of the Norwegian North Sea. They lie 10 and five kilometres respectively east of the Heimdal field. Small oil discoveries like these are normally developed withsubsea installations tied back to an existing field.

In this part of the North Sea, the Alvheim FPSO is the nearest production facility suitable for handling liquids from new discoveries. In addition to the third-party access (TPA) agreement which 25/5-9 Trell) and 25/4-2 (Trine) have secured with host field Alvheim pursuant to the regulations relating to the use of facilities by others, a coordinated development of the two discoveries is planned pursuant to section 4-7 of the Petroleum Act. Overall resources are estimated at 3.8 million scm oe. This approach helps to reduce total development costs compared with developing each discovery separately.

Discovered in 2014 (Trell) and 1973 (Trine), the two are dependent on cost-effective recovery solutions for achieving acceptable profitability. The licensees in the area have therefore implemented a number of measures which make it possible to coordinate their development, and have submitted a PDO in 2022. Production licence 036 E covering 25/4-2 (Trine) was carved out from production licence 036 BS (Heimdal), and changes in participant interests have occurred. Aker BP took over the operatorship inboth production licences in 2018, and the licensees concerned established a unitisation agreement in 2021. This means that their share of production will be the same for the two discoveries.