Decommissioning Costs can be reduced. Many costs are higher than needed due to decisions made during the initial engineering and construction of an offshore oil or gas field. Five years of decommissioning data, throughout the world have been studied. Key areas have been identified where decisions made during design have affected the eventual decommissioning costs. Examples of possible decommissioning cost savings are listed.
Economics for 60, 000 barrels of oil per day oil field show that a reduction in decommissioning costs of 50% can increase the Project Net Present Value by 13%. The five stages of decommissioning an offshore development are described with the cost percentage split for each stage using North Sea data. The major cost drivers of a decommissioning project are stated. For each of the major cost drivers practical examples are given as how the costs could be reduced during design by changing the design. These changes will increase the choices for removal. The scope of the decommissioning studies during conceptual and detailed design are listed. Finally the missing technologies will be listed as experience has shown that cost reduction and safety can be enhanced if new technology could be developed.
The guidance for project design reviews is provided to direct designers and engineers so they can consider decommissioning as part of their work.