Components used in the few existing pilot or commercial DAC plants are either general purpose products or expensive purpose-built solutions. For nearly all DAC technologies, there is an absence of DAC-specific mass produced equipment, such as air contactors, fans/blowers, CO 2 compressors, and energy units/sources, e.g., heat pumps, heat exchangers, photovoltaics, and energy storage layouts (#10). Apart from the air contactors, the other equipment are already used at commercial scale and, therefore, their conversion to DACspecific design is expected to be more straightforward, even though there is still room for improvement. For example, for technologies requiring low-temperature heat, there is room to further improve low-temperature heat pumps, opening up the use of electricity for provision of regeneration heat. Air contactors are key equipment components for DAC due to the significant airflow required for scaled CO 2 capture. To the best of our knowledge, there are currently no published comparative studies on contactor designs (e.g., conventional contactors, cross-flow columns, membrane contactors) and their performance in a DAC-specific setting (#11).