CO2 “snow” deposition in Antarctica, cryogenic CO2 capture

Industry

Gentoo Penguins (Pygoscelis Papua), Antarctic Peninsula

The concentration of GHGs in the atmosphere will have to be stabilized or lowered to mitigate or even reverse current global warming. To achieve this, current GHG emissions need to be reduced. Such mitigation strategies will however take time to deploy, and some emission sources will be difficult to mitigate. Moreover, since current atmospheric levels are already having a major warming effect, negative emission or Carbon Dioxide Removal (CDR) measures that reduce the amount of GHGs in the atmosphere are an active topic of research.

Inspired by the discovery of CO2 ice caps on Mars, Agee et al. (2013) suggested it might be possible to artificially create similarly cold conditions in the already frigid temperatures of Antarctica that would allow CO2 to 'snow' out of the air. They envision a 'depositional plant', where air would be introduced into a refrigerated chamber, which would cool the air to -140 degrees C and freeze the carbon dioxide, while remaining the other components like oxygen and nitrogen in a gaseous state. This frozen CO2 would then be deposited into a dry ice underground landfill for storage. Apart from making use of the much colder Antarctic air, which significantly reduces energy requirements for cooling, the colder air also is largely devoid of moisture.

Technological Readiness Level (TRL)

Low 1

Agee and Orton (2016) conducted some small scale experiments, von Tippel (2018) and Boetcher et al (2020) looked at energy and scaling issues, Andrea Orton conducted modeling on the climatic effects of this measure as doctoral research (2020), and a more recent study by Perskin et al (2022) explored the topic further and compared it to other precompression methods for direct carbon capture. However, the idea seems not to have been picked up broadly, and remains in a very theoretical stage. In a 2012 article by the New Scientist (Marshall, 2012), Tim Kruger furthermore highlights issues with storage, as the solidified CO2 would either have to be kept frozen, or stored in highly pressure resistant tanks.

Technological Readiness Level (TRL)

A technology with a TRL of 1-3: TRL 1 – Basic; TRL 2 – Concept formulated; TRL 3 – Experimental proof of concept

Scalability

Low 1

Agee et al (2013) claims that this technology could be scaled up to remove 1 GtC equivalent of 4 Gt CO2 from the air annually. Perskin et al (2022) equally state it might be scaled up rapidly. However, given the technical difficulties related to the project and the suggested location, and the unproven nature of the idea, this is highly uncertain. A main issue would also be power for the project, as the envisioned 1 GT/ year plant would require 16 1200 MW wind farms, and would therefore run into similar obstacles as those outlined for the idea to pump water on ice sheets (See pumping water on ice sheet). Although von Tippel (2018) estimates energy requirements of 112 to 420 GW to remove 1 billion tonnes of CO2 for a similar system, which he considers comparable to those of other CDR methods.

Scalability

Physically unable to scale; sub-linear/logarithmic efficiency of scalability

Timeliness for near-future effects

Low 1

There have been small-scale experiments, but development would likely take a long time. After that, construction would be a major undertaking given the remoteness and climate of Antarctica or the Arctic.

Timeliness for near-future effects

Implemented too late to make a significant difference

Northern + Arctic potential

Unknown 0

If found to work, this could be of major importance for the Northern and Arctic regions.

Global potential

Unknown 0

It is unsure if the technology would work, and if it could make a difference.

Cost - benefit

High 1

The cost of constructing and maintaining the facility would likely be very high. Moreover, the energy requirements would be significant, so it is questionable whether this would be the most feasible and competitive CDR method.

Cost - benefit

Cost of investment comparable to cost of avoided damage

Environmental risks

High 1

Because this project would be built in the especially environmentally sensitive context of Antarctica, special care would have to be taken to prevent serious risks. However, there appear to be several potential risks, especially those to safe and durable storage of captured CO2.

Environmental risks

Major, serious risks with a high disaster potential; multiple and cascading risks

Community impacts

Unknown 0

Ease of reversibility

Hard 1

Because the frozen CO2 would have to be stored permanently, there would probably be some difficulties with reversing this scheme fully.

Ease of reversibility

Impossible or very difficult to reverse

Risk of termination shock

High 1

Given the storage issues, the solidified CO2 would either have to be kept frozen, or stored in highly pressure resistant tanks, lest it escapes again into the atmosphere, likely leading to a quick spike in CO2 levels and subsequent greenhouse effect amplification.

Risk of termination shock

High or very significant termination shock or damage

Legality/governance

Low 1

There have been no studies on this topic, but similarly to ideas to stabilize Antarctic ice sheets (See undersea curtain), or the pumping of water on top of it (See pumping water on ice sheet), this measure would have to fit into the framework of the Antarctic treaty.

Legality/governance

Illegal or banned, or the legal regime is not suited to deployment

Scientific/media attention

Low 1

Apart from a small community around the original developers of the idea, and a couple of separate references (see for example McQueen et al, 2021; Betts, 2022), the plan has not received significant attention.

Scientific/media attention

Very low attention from individuals and/or abandoned ideas; low media attention; no commercial interest.

References

Agee, E. M., & Orton, A. (2016). An initial laboratory prototype experiment for sequestration of atmospheric CO2. Journal of Applied Meteorology and Climatology, 55(8): 1763-1770. https://doi.org/10.1175/JAMC-D-16-0135.1

Agee, E., Orton, A. and Rogers, J. (2013) CO2 snow deposition in Antarctica to curtail anthropogenic global warming J. App. Meteor. Climatol., 52(2): 281-288. https://doi.org/10.1175/JAMC-D-12-0110.1

Boetcher, S.K.S., Traum, M.J. and von Hippel, T. (2020). Thermodynamic model of CO deposition in cold climates Clim. Change, 158 (3–4): 517-530. https://doi.org/10.1007/s10584-019-02587-3

Michael Marshall, (2012), Could we geoengineer the climate with CO2? New Scientist. Available at: www.newscientist.com/article/dn22244-could-we-geoengineer-the-climate-with-co2.html [Accessed 22 July 2024]

McQueen, N., Gomes, K. V., McCormick, C., Blumanthal, K., Pisciotta, M., & Wilcox, J. (2021). A review of direct air capture (DAC): scaling up commercial technologies and innovating for the future. Progress in Energy, 3(3), 032001. https://doi.org/10.1088/2516-1083/abf1ce

Orton, A. E. (2020). Meteorological Response to CO2 Sequestration and Storage in Antarctica (Doctoral dissertation, Purdue University Graduate School). Abstract available at: https://docs.lib.purdue.edu/dissertations/AAI30504090/ [Accessed 22 July 2024]

Perskin, Jennifer, Matthew J. Traum, Ted von Hippel, Sandra K.S. Boetcher, (2022), On the feasibility of precompression for direct atmospheric cryogenic carbon capture. Carbon Capture Science & Technology Volume 4, September 2022, 100063. https://doi.org/10.1016/j.ccst.2022.100063

von Hippel, T. (2018). Thermal removal of carbon dioxide from the atmosphere: energy requirements and scaling issues Clim. Change, 148: 491-501. https://doi.org/10.1007/s10584-018-2208-0

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