Ya-Ju Chang

Challenges in Life Cycle Assessment: An Overview of Current Gaps and Research Needs

This chapter provides a comprehensive overview of current gaps of and challenges for LCA structured into inventory, impact assessment, generic and evolving aspects. A total of 34 gaps and challenges were identified. These include challenges like ‘allocation’, ‘uncertainty’ or ‘biodiversity’, as well as issues like ‘littering’, ‘animal well-being’ or ‘positive impacts’ which are not covered as often in the existing LCA literature. Each of these gaps is described by a high-level overview of the topic and its relevance to LCA, and the state of the art in terms of literature and potential solutions, if any, is presented.

Environmental energy efficiency of single wire and tandem gas metal arc welding

This paper investigates gas metal arc welding (GMAW) with respect to energy consumption and its associated environmental impacts. Different material transfer modes and power levels for single wire GMAW (SGMAW) and tandem GMAW (TGMAW) are evaluated by means of the indicator electrical deposition efficiency. Furthermore, the wall-plug efficiency of the equipment is measured in order to describe the total energy consumption from the electricity grid. The results show that the energy efficiency is highly affected by the respective process and can be significantly enhanced by a TGMAW process. The wall-plug efficiency of the equipment shows no significant dependency on the power range or the material transfer mode. Moreover, the method of life cycle assessment (LCA) is adopted in order to investigate the influences of energy efficient welding on the environmental impacts. In the comparative LCA study, the demand of electrical energy is reduced up to 24%. In consequence, the indicator values for global warming potential (100), acidification potential, eutrophication potential, and photochemical ozone creation potential are reduced up to 11%.

Life Cycle Sustainability Assessment Approaches for Manufacturing

Sustainability assessments considering the three dimensions environment, economy, and society are needed to evaluate manufacturing processes and products with regard to their sustainability performance. This chapter focuses on Life Cycle Sustainability Assessment (LCSA), which considers all three sustainability dimensions by combining the three methods Life Cycle Assessment (LCA), Life Cycle Costing (LCC), and Social Life Cycle Assessment (SLCA). Existing LCSA approaches as well as selected ongoing work are introduced, both regarding the individual approaches as well as the combined LCSA approach. This includes, for instance, the Tiered Approach. This approach facilitates the implementation of LCSA, for instance, within the manufacturing sector, by providing a category hierarchy and guiding practitioners through the various impact and cost categories proposed for the three methods. Furthermore, ongoing developments in LCC and SLCA are presented, such as the definition of first economic and social impact pathways (linking fair wage and level of education to social damage levels) for addressing the current challenges of missing impact pathways for economic and social aspects. In addition, the Sustainability Safeguard Star suggests a new scheme for addressing the inter-linkages between the three sustainability dimensions. These approaches foster the application and implementation of LCSA and thus contribute to developing sustainable processes and products.

Application options of the Sustainable Child Development Index (SCDI) – assessing the status of sustainable development and establishing social impact pathways

The needs of children and their vulnerability to diseases, violence and poverty are different from those of adults. The Sustainable Child Development Index (SCDI) was thus developed in previous work to evaluate the status of sustainable development for countries with a focus on children and triple-bottom-line thinking. This study proposes application options to put the SCDI into practice. The SCDI can be performed similarly to existing development indices, for comparing and tracing the performance of sustainable development on different geographic levels and between population groups. In addition, the SCDI can be integrated into existing social sustainability assessment approaches (e.g., Social Life Cycle Assessment and Social Organizational Life Cycle Assessment) and databases (e.g., The Social Hotspots Database) to take children into account and enhance impact assessment of social sustainability assessment approaches. As an exemplification, this study demonstrates the application of the SCDI framework to support the development of social impact pathways. Due to the importance of tertiary education in reducing poverty, a preliminary social impact pathway addressing completion of tertiary education was established. By putting the SCDI into practice, the SCDI can support decision making in child as well as sustainable development policies.