An integrated life cycle emergy analysis for environmental–economic sustainability assessment

Emergy analysis (EmA) is the quantitative sustainability method that analyses materials, energy resources, goods, or services under a common unit of solar emergy (seJ). Meanwhile, life cycle assessment (LCA) is one of the popular tools to evaluate environmental impacts. Both methods have been widely used in various applications, hence, the idea of co-jointing these two methods has been increasing to optimize the assessment's inclusivity. However, the existing integrated LCA–EmA methods are applied segmentally with minimal data integration, which has limited the potential of co-benefits in sustainability accounting. This research proposes a more comprehensive integration between LCA and EmA, known as life cycle emergy analysis (LCEmA). The process data is fully integrated, and the detailed methodological approach is presented to demonstrate the assessment process. Diaper manufacturing is selected as a case study to validate the functionality of the proposed LCEmA approach. The inclusion of foreground and background data offered in LCEmA approach considers backend processes such as electricity generation for manufacturing activities. This has shifted the sustainability hotspot from raw material extraction to the manufacturing process. This research demonstrates that the LCEmA approach can perform comprehensive analysis as a promising alternative to the existing integrated LCA–EmA methods.