Life Cycle Assessment and System Integration of Carbon Dioxide Removal: Addressing Challenges in Environmental Evaluation and Model Representation

Carbon Dioxide Removal (CDR) is essential for achieving net-zero emissions, yet its large-scale deployment presents environmental, methodological, and policy challenges. This review identifies key methodological issues in Life Cycle Assessment (LCA) for CDR, including inconsistent system boundaries, functional unit variations, and limited treatment of permanence and co-benefits. This report highlights methodologies that can improve LCA for CDR such as consequential approaches that remain underutilized despite their value for assessing deployment effects. It recommends expanding LCA frameworks to reflect full supply-chain impacts, using consistent metrics such as permanent CO2 removed. It also addresses the integration of LCA with system modeling to account for regional resource constraints, infrastructure dependencies, and long-term storage risks. The review provides a comparative assessment of integrated assessment models while underlining key limitations due to their structural aspects. Integrating LCA with system models is crucial for assessing the environmental performance and scalability of sustainable CDR. Standardization and alignment with regulatory frameworks, enhance transparency, comparability, and policy relevance.