Direct Air Capture (DAC) Programs Are Only a (Small) Part of the Carbon Emissions Solution
Carbon capture technology will not fulfill US environmental objective
Direct air capture (DAC) technologies extract CO2 directly from the atmosphere. The CO2 can be permanently stored in deep geological formations (thereby achieving negative emissions or carbon removal) or it can be used, for example in food processing or combined with hydrogen to produce synthetic fuels.
There are currently 19 DAC plants operating worldwide (Source: IEA), and all of those are operating on a fairly small scale in comparison to global emissions.
President Biden announced a $3.5-billion investment plan to speed up carbon capture technology development and deployment, in part, to help the US meet its pledge to reduce its 2005 CO2 emissions by 50%. The direct air capture program for carbon removal requires direct air capture hubs.
These proposed hubs in the US would be the largest in terms of scale of any hub operating in the world today. Specifically, each hub can remove about 1 million metric tons of CO2 emissions per year. To put this into perspective, the largest DAC plant to come online thus far is in Iceland, and captures 4kt CO2 per year. Each of the proposed US hubs would capture more than 220 times the amount of CO2 that this current largest Icelandic hub captures.
The US’ $3.5-billion investment will fund the creation of 4 of these hubs, which therefore, will remove about 4 million metric tons of CO2 emissions per year. 4 million metric tons of CO2 emissions is only 0.24% of the 1,650 million metric tons of CO2 reduction required between 2020 and 2030 for the US to meet its CO2 emissions reduction pledge.
We believe that any step taken to a more sustainable world is worth exploring, and an added benefit could be that the technology is proven to function as expected and can be scaled up to be more efficient and effective. Even so, it is clear that DAC programs will not contribute heavily to the CO2 reductions required.