Decommissioning Insight 2016 - Oil & Gas UK

DECOMMISSIONING INSIGHT REPORT 2016

7.3 Topside and Substructure Removal (UK Continental Shelf Only) The weight of a platform has little effect on some of the expenditure associated with removal, including removal preparation, vessel mobilisation, sea-fastening, transportation and load-in onshore. This can again result in a larger cost per tonne forecast for topside removal for the smallest and lightest structures commonly found in the southern North Sea and Irish Sea. The cost per platform, however, is significantly lower in these regions.

Central and Northern North Sea and West of Shetland

• The average removal cost per tonne forecasts in these regions from 2016 to 2025 has fallen by a smaller amount than in other areas of the UKCS (less than 10 per cent) to £3,000 for topsides and £4,400 for substructures.

• The range in costs per tonne remains high, particularly for substructure removals, due to the variation in substructure types and weights and planned removal methods.

• For the 96 projects classified as provisioning estimates in these regions, the removal method may not yet be determined as operators carry out comparative assessments to determine the best approach. As removal methods become more defined, this can explain the changes in the cost per tonne forecasts from one year to the next.

64