eli5: Co2 challenge issue


Please excuse my ignorance – I’m not a scientist but always wonder: there’s too much CO2 in the atmosphere. There have been successful trials with extracting it from there. CO2 goes into drinks. And yet it is artificially created for that specific purpose. I even heard claims that beer manufacturers have been running short on CO2 due to supply issues and Covid and what not. Can you explain?

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5 Answers

Anonymous 0 Comments

The atmospheric concentration of CO2 doesn’t have to be that high to be too high. It’s about 400 ppm or 0.04%. Far too low to extract it from the air at an industrial scale.

Anonymous 0 Comments

I’m not really a professional on this, but I’d presume the trials to extract CO2 from the atmosphere have been very costly. Otherwise that’s what we would be doing instead of cutting down emissions, right? At least that’s how I see it with the levels of CO2 being the biggest factor for climate change.

Anonymous 0 Comments

There is no easy way to trap CO2 from the air itself. Doing so is energy and resource intensive… Which defeats the point.

Doing it at the source (as in, the chimney etc.) is viable, but still technologically difficult (CO2 isn’t a particularly reactive gas).

Anonymous 0 Comments

There’s a set of technologies called “carbon capture and storage”.

These do what you’re thinking about: they “capture” CO2 from the air (or directly from power plant emissions) and then “store” it in some way. For example, CO2 might be pumped into the same kind of underground reservoirs that shale gas gets extracted from. Of course, whatever that storage is needs to be pretty reliable – you don’t want all that CO2 to just start leaking back out again.

This isn’t easy or cheap to do at the scale necessary to make a difference. To take the CO2 concentration in the atmosphere half way down to pre-industrial levels means capturing and storing 50 gigatonnes of CO2. That’s fifty billion tonnes, all of which has to both be captured and stored.

At the moment the technology just isn’t there to make it feasible.

Anonymous 0 Comments

There’s a lot of confusion and misrepresentation in this thread. The facts are:

– Atmospheric CO2 capture technologies work by binding the CO2 molecules to other molecules — namely oxygen and hydrogen — to create sugars. About 70% of the cost of atmospheric CO2 capture technologies actually comes from H2O-splitting. Note if the cost of H20-splitting were meaningfully reduced, not only would atmospheric CO2 capture technologies be more viable, but a hydrogen economy would be more viable as well.

– Industrial CO2 is usually captured from power plant exhaust and it’s captured in a pure, liquid form. I suspect this product is cheaper (even with ongoing inflation) than the product produced by atmospheric CO2 capture technologies, but it’s worth emphasizing it’s actually a different product anyhow.

– Some of the CO2 in beer is a byproduct of the fermentation process which produces alcohol, resulting from the break-down of sugars. But additional CO2 is added in its liquid form. And this CO2 cannot be added as more sugars to be broken-down by the fermentation process because that would also increase alcohol levels.

– CO2 in pop or soda is added in its liquid form. This CO2 cannot be added as more sugars because there’s no fermentation process in pop or soda manufacturing, the product would just have more sugar.