Features of CO2 Capture from Air
Among several carbon capture and emission reduction strategies, direct air capture of CO2 (DAC) has several unique features.
- DAC systems do not need to be located next to any source of CO2 emissions like flue gas streams since atmospheric air is available nearly everywhere.
- The heat-driven Climeworks DAC systems can be powered by waste heat that cannot be used otherwise, for example waste heat of a fuel synthesis plant. When powered by waste heat, the effective energy penalty of the process can be very low.
- The major share of the required energy, which is needed for the regeneration of the sorbent material, is similar for DAC and flue gas CO2 capture processes. Both shall therefore be considered as complementary technologies, depending on the specific application.
- While today DAC is one of several CO2 sources for the production of renewable hydrocarbon fuels (“Power to Gas” / ”Power to Liquid”), in the long term only DAC can enable storing renewable energy within a closed carbon cycle and producing carbon-neutral transportation fuels on a global scale. Carbon-neutral fuel strategies that are based on Climeworks DAC systems therefore build on a long-term sustainable solution.
- While DAC can enable “negative emissions”, i.e. net removal of CO2 from the atmosphere, in the long term, DAC shall not be seen as alternative to current emission mitigation strategies, since the time scales for deploying DAC on a global scale are too long to consider DAC as a backup-plan today.