This is a fantastic article. It looks at the state of carbon capture, discusses merits and challenges, and is all around well written and interesting. It's long, but make a cup of coffee and read through it. It is worth it.
My thoughts:
This scenario would involve scaling up the industry to make up for some 10 to 15 percent of global carbon reductions, he said. But that would mean growing the industry’s impact by around 30 to 40 percent annually, every year, for the next quarter century.
Holy crap that's a lot of needed growth. The article later indicates that there are S O O many technologies out there, and no general consensus on what is best. Because of a lack of concerted effort, the 30-40% growth might as well be the moon IMO.
Estimates suggest that technology-based carbon removal outfits extracted anywhere from 10,000 to more than a million tons of carbon dioxide in 2023, compared to more than 37 billion tons of global emissions.
Kek. That's so laughably small, and yet we continue to push tech-bases C storage. To be clear, I really, really like the brick storage methods the company in the article mentions for a few reasons:
- It isn't picky on feedstock
- It's relatively cheap
- It stores the biomass deep, in presumably low oxygen environments
- It uses a film to protect the bricks from decomposition
I don't like that it still relies on old underground mines, as that can make things expensive, and that, while there are no shortage of mines, they aren't always conveniently located. You still have to transport the feedstock too.
technologically and economically unproven, especially at scale, and pose unknown environmental and social risks.
Long-term storage requires long-term monitoring which can be expensive, and unsurprisingly, is time consuminf. Further you don't know if a new tech is going to work for a long time, so bear the financial and technical risks of the thing falling flat on its face.
For the formative industry to actually matter to global climate change, it will have to remove up to 10 billion tons every year in the not-too-distant future.
Again, the moon, given our current removal
These land-based approaches could quickly reach the necessary scale, and the techniques could account for 2.6 billion tons of annual carbon reductions by 2030
Rub here is that these are essentially 'buffering capacity' projects and have the risks of fire/long term decomposition, as the article points out.
I do think replanting efforts are important, but I can't see them being the be all end all.
Sludge underground
Screams in hydrogeologist
How do you confirm that this doesn't contaminant groundwater? Doing so would require hydrogeological modeling and that's not cheap or easy
Enhanced rock weathering
Squints in geochemist
While this could work, generally geochemistry reactions are slow. The carbonate reaction is relatively easily reversed if stuff is left out to weather, so you're back to requiring mines, or an engineered cover.