PNNL

Abstract

Limiting the rise in global temperature to 1.5°C will rely, in part, on technologies to remove CO2 from the atmosphere. However, many carbon dioxide removal (CDR) technologies are in the early stages of development, and there is limited data to inform predictions of their future adoption potential. Here we present a new approach to model adoption of early-stage technologies such as CDR and apply it to direct air carbon capture and sequestration (DACCS). Our approach combines empirical data on historical technology analogues with early indicators of technological innovation to model a range of plausible future adoption pathways. We use these pathways as inputs to an integrated assessment model (the global change analysis model, GCAM) to evaluate the effects of DACCS adoption under a policy to limit end-of-century temperature change to 1.5°C. Across analogues, DACCS adoption is generally lower than levels currently featured in GCAM and does not reach gigatonne scale by 2050, suggesting deeper emissions reductions will be required over the next few decades. If DACCS follows patterns seen for faster-growing analogues (e.g., wind power or nickel mining), it can reach several gigatonnes by the end of the century and contribute meaningfully to climate change mitigation. However, if it follows pathways of other plausible analogues (e.g., railroads and gas pipelines), it fails to reach gigatonne scale by the end of the century. Less similar analogues, such as solar photovoltaics, can reach gigatonne scale by 2050 and may represent possible removals in an emergency adoption scenario.