Putting costs of direct air capture in context

This working paper provides an overview of various estimates and claims on direct air capture (DAC) of carbon dioxide, and places them in a broader context of global climate policy. Unlike other techniques of climate engineering, DAC has received significant attention from startups since its main issue is deemed to be the direct implementation cost (not side effects or social concerns), which could be significantly reduced with successful innovation. Publicly available sources demonstrate that there is a huge range of cost estimates with three orders-of-magnitude differences, with the upper end on the order of 1000 USD/t-CO2. Cost values reported by private companies tend to be lower than academic estimates, though there is no a prior reason to believe that either is inherently biased. In light of this huge uncertainty, the only way to resolve it may be to build an actual plant at scale, as a leading scholar put it. It is nevertheless important to monitor technological progress since climate policy analysis would increasingly require such cost parameters and because technology understanding would guide policy of research and development of this nascent technology. A periodic review of this nature would provide a basis to ascertain the progress of DAC technology development.