Environmental trade-offs of direct air capture technologies in climate change mitigation toward 2100

On June 25, 2022, the journal Nature Communications published the article “Environmental trade-offs of direct air capture technologies in climate change mitigation toward 2100” co-led by IAMC members NREL and PBL. The study applies a prospective life cycle assessment framework to evaluate two direct air capture (DAC) technologies in a series of climate change mitigation scenarios. It reveals that electricity sector decarbonization and DAC technology improvements are both indispensable to avoid environmental problem-shifting. Decarbonizing the electricity sector improves the sequestration efficiency, but also increases the other environmental metrics like terrestrial ecotoxicity per tonne of CO2 sequestered via DAC. These increases can be reduced by improvements in DAC material and energy use efficiencies. Regional environmental impact variations highlight the importance of smart DAC siting related to energy system planning and integration. DAC deployment aids the achievement of long-term climate targets, its environmental and climate performance however depend on sectoral mitigation actions, and thus should not suggest a relaxation of sectoral decarbonization targets.