The CDR series: Direct Air Capture

Carbon dioxide removal is necessary to achieve net-zero

Direct Air Capture (DAC) is one of the methods considered to generate the negative emissions needed to achieve carbon neutrality (see our previous report on this topic). DAC can either remove CO₂ from the atmosphere or provide a continuous, easy-to-monitor source of CO₂ for various current and future uses. To date, the technology is still at an early stage of development, with about 20 installations deployed worldwide, either in the pilot or early commercialisation stage.

The considerable advantages of DAC, particularly regarding the permanence of CO₂ sequestration, are currently outweighed by the high costs and high energy requirements of existing technologies. Ongoing RD&D activities could help improve DAC performances by optimising current processes or developing alternative technologies. A very dynamic ecosystem has started to form around DAC, supported by ever-increasing funding, and projects of increasing scale are announced in the coming decade, which may allow the technology to go down the experience curve by being deployed in different contexts.

What perspectives?

The deployment potential of DAC remains uncertain, and estimates vary widely across different scenarios. Its role in climate action therefore still needs to be clarified, especially in comparison to other CDR methods. In order to ensure sustainable deployment of the technology, it is necessary, as it develops, to assess its societal impacts, in particular with regard to possible conflicts of use in terms of low-carbon energy, and to consolidate existing life cycle analyses.

DAC is a promising technology, whose exact role will become clearer in the years and decades to come. It should be remembered that this technology is part of a set of contrasting CDR methods, methods that are themselves only a necessary but limited complement to the drastic emission reductions that must be made in the first place.