Purpose:The assessment and improvement of sustainability impacts of products is integral to achieve sustainable development. A way to assess the impact of a product over its entire life cycle on all three dimensions of sustainability (environment, economy and society) is Life Cycle Sustainability Assessment (LCSA). LCSA suggests to carry out three complementary assessments: Life Cycle Assessment (LCA), Life Cycle Costing (LCC) and Social Life Cycle Assessment (S-LCA). While LCA is widely applied across various industries, the use of LCSA at industrial companies is still scarce. This is, inter alia, due to the challenges in data acquisition in S-LCA and missing support in decision making based on LCSA results as well as their implementation in the decision processes at companies. This thesis aims at remediating these shortcomings to achieve its overarching goal: Increasing the applicability of LCSA to identify and implement product sustainability improvement potential. For this, three research objectives were defined to address the main impediments. First, an approach to select social indicators and to focus primary data collection in S-LCA. Second, a method to interpret LCSA results for decision makers. Third, a mechanism to integrate LCSA based results into product-related decision making at an automotive company.
Methods:To put the LCSA framework into practice at an automotive company, it was applied to the component level of a vehicle to assess the impact of every component over its life cycle. In the proposed framework, criticality scores for every LCSA dimension were defined. They were calculated based on the relative performance of a component in the respective LCSA dimension (LCA, LCC and S-LCA) to the rest of the components of the assessed vehicle. This conceptual approach formed the bearing for the integration of the individual research objectives. The three research objectives were addressed in individual publications. The results of these separate papers were combined to increase the applicability of the conceptual approach of the LCSA framework. Multi-Regional Input-Output (MRIO) databases were assessed regarding their possible use to address the first research objective.The findings were applied to enable an assessment of the S-LCA dimension in the LCSA framework.A study on the weighting of sustainability dimensions by decision makers in an automotive company was carried out to tackle the second research objective. The results were used to determine an overall LCSA impact result for every component of a vehicle. To address the third research objective, the customer added value of product sustainability features was investigated. The results were used to create a mechanism that enabled the integration of the assessment results of the LCSA framework alongside other indicators in product-related decision processes at an automotive company.
Results:Supply chain analysis based on MRIO analysis did not offer substantial support for focusing primary data collection in S-LCA. Therefore, a material-based appr...