Decommissioning vs. reusing offshore gas platforms within ethical decision-making for sustainable development: Theoretical framework with application to the Adriatic Sea.

This paper integrates ethics into decision-making for sustainable development to help planners choose between decommissioning and reuse of an offshore gas platform within a social perspective. To do so, I match multi-criteria analysis (MCA), cost–benefit analysis (CBA), weighted life-cycle assessment (WLCA), and monetary life-cycle assessment (MLCA) to four main ethical standpoints: MCA for duty to the current generation by minimising impacts (strong sustainability in a linear economy), WLCA for duty to the current and future generations by minimising impacts (strong sustainability in a circular economy), CBA for duty to the current generation by maximising welfare (weak sustainability in a linear economy), and MLCA for duty to the current and future generations by maximising welfare (weak sustainability in a circular economy). Analytical results demonstrated that reuse of the platforms is more suitable than decommissioning in a linear economy. Thus, the decision on decommissioning vs. reuse is primarily a matter of inter-generational equity. Numerical results with non-marginal assessments for a case study in the Adriatic Sea suggested that support for reuse of the platform is 100% of the solution space based on MCA , 72% based on WLCA, 89% based on CBA , and 83% based on MLCA. However, after accounting for the estimated impacts, WLCA no longer supports reuse. Thus, the decision on decommissioning vs. reuse depends secondarily on the sustainability perspective. Sensitivity analyses based on greater positive and negative perceptions of reuse and with greater social and environmental concerns showed that reuse is a robust choice with respect to perceptions (i.e., the information gap is not relevant) and concerns (i.e., stakeholder representativeness is not significant) for all sustainability paradigms and economic approaches. Therefore, the main policy implications are that the avoided decommissioning costs should be shared in terms of inter-generational distributive justice; and that employment and biodiversity benefits from reuse should be stressed within a strong sustainability perspective. Image 1 • Multi-Criteria and Cost-Benefit for Strong/Weak Sustainability (SS/WS) in linear economy LE. • Weighted/Monetary Life Cycle (WLC/MLC) for SS and WS in circular economy CE. • Reuse in LE > CE from analytical results: MC > WLC and CB > MLC. • Reuse at estimated impacts from numerical simulations: MC > CB > MLC, no for WLC. • Robustness for perceptions and concerns from sensitivity analyses: MC > CB > MLC > WLC. [ABSTRACT FROM AUTHOR]