Platform removal marks end of era in Norway’s energy history

July 10, 2025, by Dragana Nikše

Norwegian state-owned gas grid operator Gassco has completed one portion of the decommissioning job it is undertaking at a field in the North Sea.

Heimdal riser platform decommissioning; Source: Gassco

The Norwegian player disclosed having completed the offshore removal of the Heimdal Riser Platform (HRP) in the North Sea. Together with the Equinor-operated Heimdal processing platform, it formed part of the Heimdal Gas Centre in block 25/4.

According to Gassco, Equinor, as the technical service provider, contracted Heerema Marine Contractors with Aker Solutions acting as a subcontractor for the project.

The lifting operations were done by Heerema, the same company that installed the Heimdal platform on the field in 1985. The company’s largest heavy lift vessel, Sleipnir, got the job done, and the structure was brought onshore to Aker Solutions’ facilities at Stord, where dismantling and recycling are underway.

Around 98% of the materials are envisaged to be recycled, and Gassco is looking into ways to do the same with the remaining 2%, mostly isolation materials. Furthermore, all water used to rinse the structures is collected and treated before being discharged.

The decommissioning marks the end of an important chapter in the region’s energy infrastructure, but thanks to the subsea connection Heimskringla, the gas export will continue.

As stated by Equinor, the development of Heimdal, along with gas exports from Statfjord and Gullfaks, formed the basis for establishing the Statpipe pipeline, described as the cornerstone in the Norwegian gas transport system.

The Heimdal field was discovered in 1972, with production starting in 1986. According to the Norwegian Offshore Directorate, the production from the field stopped in 2020, having produced approximately 700 million barrels of oil equivalent (boe). The platform was used as a gas processing center until mid-2023.

Based on information from Equinor, after the main part of the gas reserves in the Heimdal reservoir had been produced towards the end of the 1990s, the field was modified to receive and process gas from the Huldra, Vale , and Byggve/Skirne fields. Gas from Atla and Valemon was also subsequently routed to the field.

HRP was installed to serve as a transit point for gas exports from the Norwegian continental shelf. Since the production from the fields that process gas at Heimdal started to decline, it was decided that the operation would be shut down in June 2023. The HRP has remained unmanned since.

After receiving the green light to start decommissioning operations, Gassco disclosed that the work would be done in three phases. Phase 1 involved the removal of hydrocarbons and water filling in 2023.

The following stages are Phase 2 and Phase 3, entailing the disconnection of the pipeline from the Heimdal riser platform, the removal of remaining structures, and other final activities in preparation for the permanent abandonment of the field and safety zone. The end of work is envisaged for 2028.