A Multi-Objective Optimization Methodology for Enhanced Sustainable Strategy Decision-Making: A Life Cycle Assessment Perspective

Embedding sustainability into industrial practices has become an essential strategy for addressing environmental, economic, and social challenges in manufacturing and consumption. This approach ensures that products meet current demands without compromising the ability of future generations to satisfy their own needs. Our previous study introduced a novel four-step methodology for sustainable product lifecycle management, utilizing multi-objective life cycle optimization. By enhancing the understanding of trade-offs between different sustainability objectives, this methodology enables a comprehensive evaluation of various product design alternatives at the early design stage, considering material selection, manufacturing processes, usage scenarios, and end-of-life strategies. Building on prior research, an advanced multi-objective optimization framework has been developed to support sustainable strategy decision-making. The proposed methodology provides decision-makers with data-driven recommendations through four key steps: (1) identifying potential sustainability strategies, (2) conducting a cost-benefit analysis of these strategies, (3) formulating an optimization model for sustainable decision-making, and (4) solving the optimization problem using the weighted sum method. Sustainability strategies are systematically evaluated across four key life cycle assessment (LCA) stages: material selection, manufacturing processes, usage phase, and end-of-life treatment. Cost-benefit analysis is performed based on initial costs and return on investment (ROI), incorporating economic, environmental, and social dimensions. Environmental and social ROI are assessed using life cycle impact assessment indicators such as global warming potential and eco-toxicity. The optimization model can be tailored to different organizational contexts by adjusting system boundaries, strategy constraints, and objective functions to align with corporate sustainability goals or the United Nations’ Sustainable Development Goals (SDGs). Implementation of this methodology is currently underway in an industrial case study, with results and discussion forthcoming. By providing a structured and quantitative framework, this research aims to facilitate the integration of sustainability into strategic decision-making and policy development. The approach is expected to serve as a foundation for more advanced models of sustainable strategy decision-making across various sectors, with potential extensions to broader social impact considerations. Furthermore, by offering a quantitative basis for sustainability strategies, this study supports evidence-based policymaking and contributes to the advancement of sustainable product design and manufacturing practices.