The Net-Zero Carbon Dioxide Framework for Life Cycle Assessment of Carbon Dioxide Capture, Utilization and Storage Techniques

Carbon dioxide (CO₂) Capture, Utilization and Storage (CCUS) is a technology that can substantially limit CO₂ emissions from point source emitters, though it is understood that point-source CCUS does not mitigate all emissions from value chains using fossil feedstock. To allow CCUS technologies and systems to operate in future settings, they will need to abide by a strict net-zero CO₂-eq-emissions constraint, meaning additional measures like CO₂ removal may be needed to compensate for residual greenhouse gas (GHG) emissions. To help design truly net-zero CCUS systems, the net-zero CO₂-eq-emissions framework was developed. This chapter exemplifies this framework by using two CCUS case studies — seasonal energy storage for intermitted renewable energy supply (iRES) and iron and steelmaking. Life Cycle Assessments (LSAs) are reported on the whole value chain of these two systems for climate change and other environmental impacts to understand the potential trade-offs, while the net-zero framework is used to design for zero-GHG emissions.