Looking at goals and scopes in LCA: Environmental assessment of carbon capture and utilisation for technology development

Licentiate thesis, 2024

This licentiate thesis explores the goals and scopes of life cycle assessment (LCA) studies in the field of carbon dioxide capture and utilisation (CCU), within the context of technology development. In LCA, the goal of a study guides method choices, thus aligning the assessment and the interpretation of results to its purpose. This is especially important for emerging technologies like CCU, where early-stage LCA studies can influence development in stages characterised by uncertainty. Understanding the goals and scopes of LCA studies is essential, particularly if results are to effectively inform technology development. For this, the research builds on a methodological review of published LCA studies of CCU systems, focusing on their goal definitions and scope definitions. In addition, a case study was performed via an LCA study on a specific CCU system, the PYROCO2 process. In this case study, there was an emphasis on goal definition and its relation to knowledge needs in technology development. The results of the methodological review indicate that LCA studies of CCU systems often have unclear goal definitions, making results difficult to interpret. The LCA case study sets clear goals to address knowledge gaps in technology development and points to a need for multiple LCA studies to better inform on the many aspects considered during technology development. These findings suggest that separating goal definition from scope definition is useful, but current practices and guidance on defining and linking them are weak. Improving goal definition and its connection to scope is necessary for better methodological choices and clearer communication of outcomes.