Troll Gas comprises the Troll A platform, the Kollsnes gas processing plant west of Bergen and the pipelines between the platform and the land plant.

Norske Shell was responsible for the first gas development phase on Troll, which received a green light from the Norwegian parliament (Storting) in December 1986.

Four years later, Statoil and Shell agreed to move the processing facilities originally due to be installed on the A platform to a plant on land at Kollsnes west of Bergen.

This made it possible to build a simpler offshore gas production installation than originally planned, with smaller staffing.

Troll A is the tallest structure ever moved by humans over the surface of the Earth. Its concrete support section has been built for a producing life of 70 years. The platform is the only one of its kind on the NCS that is powered electrically from land.

Statoil took over as operator for Troll Gas from Norske Shell on 19 June 1996 with gas coming on stream in the first half of that year, marking the completion of the gas development.

Contractual gas deliveries began flowing from the field to continental Europe under the Troll gas sales agreements on 1 October 1996.

Initial deliveries under these contracts, which began on 1 October 1993, were provided from Statoil’s Sleipner East development in the North Sea.

Declining pressure in the Troll reservoir means that more compression is needed to help drive gas production through the pipelines to the processing plant at Kollsnes.

Two compressors have accordingly been installed on the A platform, and new technology allows these units to be powered from land.

That in turn means zero carbon dioxide and nitrogen oxide emissions from the installation or the processing plant.