EMBARGOED 0.01 GMT 4 Dec 2023 - Assessing the relative costs of high-CCS and low-CCS pathways - Advanced copy(2)

These figures likely underestimate the cost difference between the two approaches because they suppose that the costs for all types of CCS facility are at the very lowest end of the ranges estimated in the academic and grey literature. [...] And as recent scenarios were prepared for the IPCC’s AR6, and as IPCC assessments are commissioned and endorsed by virtually all of the world’s governments, one can infer that the existence, use and credibility of the scenario database are all broadly endorsed by the very governments that will be making essential policy choices on decarbonisation in the years ahead. [...] For other sources, such as iron and steel works, the capture element must be installed additionally and can make up 70-90% of the total cost.35 • The capture cost varies depending on the concentration of CO2 in the mixture entering the capture unit. [...] We construct a reduced-complexity representation of the energy system and carbon sequestration technologies by selecting 15 variables representing global deployment of the most important non-CCS-related technologies of the energy system, and nine variables representing global deployment of the most important CCS-related technologies included in the AR6 database; these are shown in Table 2. [...] Table 3 shows the costs of non-electricity-related technologies used in the main specification of the model and provides context for the values chosen.