The largest carbon removal plant is here, and bigger ones are on the way

Probably worthless as a solution, but it seems to me like a good quantitative tool to start fining at a realistic cost. I.e. VWs fines for emissions falsifications were at best based on first estimating with fantasy offset costs instead of a hypothetical build out cost.

The math works out just fine.

We have the available land and the technology and it's only a matter of cost.

If we price carbon pollution properly, with more and larger taxes, the corporations producing most of the CO2 pollution will gladly pay slightly than the taxes less to clean it up.

So, it's only a matter of working backwards from the cost of these machines and their deployment at scale to figure out what the carbon taxes should be and aligning those. Phase in the new taxes as we built out the capture systems and then when we've got scale and weaned ourselves off of the worst carbon polluters, we can lower the taxes to maintenance levels.

Not doing this is pitiful, but as long as people like you keep saying the math doesn't work and using that ignorance as an excuse to not do the one thing that must happen, legislate real carbon taxes, it obviously won't happen.

We have the technology, we lack the political will. That will be the end of humans and much other life on Earth I fear.

Not a lot. Directly on the emissions at their origin, like capturing inside a cement plant, sure. In a city or region near the cement plant not so much.

The difference is probably 1-15 ppm depending on the city.

(Making up numbers for the example,) imagine 420 ppm in remote Iceland and 425-430 ppm in NYC. Now consider the cost of land in the two locations and the couple percent difference in CO2 concentration clearly isn't at all worth it.

Iceland also has volcanoes and lots of accessible underground basalt which makes this form of storage work best.

Similar at the DAC level but TI takes the captured CO2 and combines it with solar powered electrolysis created hydrogen in a methanation process to create a liquid fuel, while Climeworks combines the CO2 with water and pumps that carbonic acid underground to store it permanently as rock.

For the DAC, both companies use some form of chemical absorption or adsorption and big fans to move a lot of air, but the specifics of their filters, materials, and configurations don't seem to be public.

Climeworks is faster out of the gate, but I think TI plans to go bigger over the long term, perhaps 100-500 times bigger. Both are not ready for large scale without massive subsidies or more and much higher carbon taxes. They're both meaningless in the big carbon picture for the foreseeable future and probably will be for multiple decades. But, maybe as we get into the second half of the century, one or both will have a meaningful impact, or inspire others to similar outcomes.

DAC can work if we price carbon with DAC in mind. If we continue to pretend CO2 pollution doesn't matter much, it won't work.

Possibly forming concrete underground? Doesn't concrete absorb CO2 while curing?

Water plus carbon dioxide gives you a carbonic acid solution which when mixing with metal oxide-bearing rocks like basalt (rich in calcium and magnesium, etc.) forms stable carbonate minerals like calcite and magnesite.

This is high school chemistry stuff, right? Or was my poor Southern state public HS education actually exceptional?