Currently, the only commercial plants in the world are operated by Climeworks. They have quoted costs or prices of $500-600 t-CO2 -1 in 2019 and €1000 t-CO2 -1 , specifically from the Orca plant, in 2021. However, our FOAK cost estimates are $1300-3100 t-CO2 -1 for a case study in the USA paired to nuclear electricity. These costs are perhaps not entirely comparable, given the lack of information on cost breakdown and whether their quotes include compression, transport, and storage. For example, if