387 – Direct Air Capture
Guest: Peter Psarras Host: Markus Völter Shownoter: Simon Bretschneider
The climate situatation is getting more and more dire, and in order to reach the goals the international community has set for themselves, engineering solutions seem increasingly necessary. After talking about solar geoengineering in episode 385, we will look at direct air capture in this episode. Direct Air Capture is a family of technologies that allow the extraction of CO2 from the atmosphere. My guest Peter Psarras explains the technology, the economics and also the political and moral challenges associated with the technology.
Peter Psarras is introducing himself00:02:10
DAC (direct air capture) | CCS (carbon capture and storage) | Point source capture | CO2 | Lithosphere | Life cycle emission | Carbon neutral | Climate crisis
How does it work? Physical mechanism, chemical processes00:11:15
Concentration of CO2 in air | Physisorption | Desorption | Energy demand for DAC | Sorbent for CO2 capture
Representative Example of chemical/physical processes to bind CO2 in the sorbent00:19:12
Climeworks | Amine absorber CO2 | TRL (Technology readiness level) | LCA (Life cycle analysis) | Carbon engineering | Solvent based carbon capture approach | Overview absorber materials | Direct air mineralization | IPCC Report | Reforestation | Orca plant | Electric swing approach
Economics of CO200:56:30
Regenerative agriculture | Ocean alkalinity enhancement | Heirloom CO2 DAC | Advanced market commitment for CO2 | Cost Curve DAC | Carbon Credit | X Price Carbon Removal | Carbon Storage in Concrete: | Moral hazard | Scaling of carbon removal | Short and longterm cost of climate change
BECCS (Bioenergy with carbon capture and storage) | Biomass | Waste biomass | Carbon mineralization | Enhanced weathering | Ocean acidification | Carbonate and bicarbonate cycle | Blue carbon | CO2 concentration in seawater | Electrochemical CO2 capture
Wrap up and conclusion01:34:41
Loved the show!
Glaringly absent was nuclear energy.
My envelope math, which is probably nothing as sophisticated as yours, comes out in the neighborhood of a PW-year to get us from where we are now to 280 ppm CO₂, allowing for a little slop upward, to wit:
You have: (420 – 280) * 7.82 gigatonne * 1 mole / 44 g * 394.4 kJ / 1 mole
You want: PW year
(420 – 280) * 7.82 gigatonne * 1 mole / 44 g * 394.4 kJ / 1 mole = 0.31097418 PW year
This is the kind of number that implies things like liquidating and shutting down the entire global fossil fuel industry in order to do something that isn’t deeply un-serious.
Help me understand why you’re framing this inside of capitalism, with all *its* moral hazards, instead of concluding that this problem mandates dismantling capitalism itself.
A few notes on the numbers above:
7.82 gigatonne is what a ppm of the atmosphere weighs.
394.4 kJ/mol is in the neighborhoold of the Gibbs free energy it takes to turn a mole of CO₂ into graphite.
I am very interested in the topic of this episode. However, it is extremely difficult for me to understand your guest’s English. I understand your question to him and your rephrasing of what he said.
It is the only episode where I stopped listening before the end.
I would like to know if this is due to my inadequate English skills, or if other listeners have had similar experiences.
Never understood a native English so bad, as your guest in this episode. The most understandable was his constant “you know…, right…, you know…, you know…, right…” phrases. NO, WE DON’T KNOW! Why would we listen, if we know everything already?
A shame, as the topic is so interesting and important! Markus, maybe you can find another person to discuss that topic with again, maybe in German language, as it’s too important to not be understood.
All the best ;)
I am also not a native speaker and had no problem understanding the guest.
I really liked this episode, and you were correct that the broader economic/technology assessments part was also quite interesting. I was sorry to read that other listeners had a problem with the guest’s speaking. As a native English speaker it was no problem for me, but even I was annoyed with his use of “you know”… But that is just one of those annoying American verbal fillers.
Markus, at one point you were really struggling to understand the comparative cost of these technologies. I think you could have asked something like “at $200 per ton of captured carbon, how much would that add to the cost of a typical airline fare if that emission was offset by DAC”. By my quick calculations, a trip from Ney York to London emits about 625kg/passenger, so would cost an additional $125 per passenger to capture. Certainly not a small added cost, but it could be tolerated.
Tod, indeed, yes, that is a good question that I should have asked. Thanks for the calculation!
Nuclear was not “missing”, since this was not a show about fixing climate change, but about DAC. I agree that nuclear should play a bigger role, but it wasn’t the point of this episode. Why I am framing it inside of capitalism? a) because that’s the system we have, b) I don’t think we’re going to get rid of it, and c) because the show was about DAC and not about whether capitalism is good or bad.
I finally had time to listen to this episode. I had no problem understanding your guest, but I had to turn down my listening speed (from 1.6x to 1.4x) to follow along. This was again a very interesting discussion which was going into sufficient details about the subject as well as giving a broader view to place this on the “climate change”-map. Also, it gives a feeling how little we are doing now and how “expensive” it will be to clean up the mess in the future. Every ton we emit has to be removed with tremendous cost in the future. It is so frustrating…
Markus: the link to the guest’s homepage still leads to Prof. Wambachs website (copy/paste).
Hmmm, interesting episode, but a bit too optimistic about the technology. Peter sometimes sounded as if he gad to convince himself, listing all kinds of caveats (great) but not always following up on them.
As a slight cynic, I would say that one reason why DAC is being pushed by some actors is that it’s something that on can build a profitable business model around. Saving energy is obviously a good idea, but it’s hard to sell as a service. But DAC you can easily sell.
One thing I found quite shortsighted was the proposal to use fossil fuels to drive DAC. Even if we assume that the CO2 is sequestered for a long time (and we really talk geological time periods here), fossil fuels are limited. If we use half of them to clean up the other half, they will run out twice as fast…