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Carbon Removal Technologies

carbon.ycombinator.com

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Re: Carbon Removal Technologies

#601

Post by notpg »

strainer wrote: post #596
cjrd wrote: post #579

Earlier quoted context omitted.

Cows are ruminants, so their production of methane is a necessary component of the fermentation that takes place in their digestive track. Also, somewhat surprisingly, "free range grass fed diets" lead to more methane production then cows fed grain diets (factory farmed cows). See https://www.fcrn.org.uk/sites/default/files/project-files/fc...

Grassfed does not necessarily lead to more methane production, it depends on the mix of grass and secondary vegetation, on the grain mix being compared to, and on potential supplements. https://prairiesoilsandcrops.ca/articles/volume-1-3-print.pd...

Just reading the article you provided and "Feeding high grain diets to cattle unequivocally lowers the formation of CH4 in the rumen." seems to disagree with what you're saying?

Re: Carbon Removal Technologies

#602

Post by andersha »

GreeniFi wrote: post #2

We already have carbon removal technology. They’re called trees. [Edit] I’m not being facetious. 40% of emissions are as a result of poor land management. We’ll need all the technological help we can get, but if we can’t manage land as carbon stores - not sources, we’re not going to win this race.

We already have carbon removal development. It's called regenerative agriculture.

Regenerative agriculture is about harvesting sunlight (free resource), utilizing plants photosynthesizing abilities. Plants are a part of a larger ecosystem including producers, consumers and decomposers.

Plants exudate sugars feeding the soil microbial life, sugars from the photosynthesis where atmospheric carbon dioxide is converted into sugars. Large herbivores eat the grass, holistic grazing keeps the animals moving mimicking predators and the defensive herding mechanisms for efficient animal impact. The timed regrowth will let the plant photosynthesize more carbon dioxide, while the walking sun powered compost machine (cow) decomposes the organic matter and leaves it for further decomposition and utilization.

We have huge areas where desertification is happening [1] because of wrong management. Holistic Grazing is a easy implemented, low tech, approach with great benefits for capital, social and ecological level.

Regenerative agriculture is also covering land management in less brittle environments, field production, notill, utilizing plants, the soil community and the only truly free available resource sunlight.

[1] https://youtu.be/vpTHi7O66pI?t=157

Re: Carbon Removal Technologies

#603

Post by ajnin »

DoctorOetker wrote: post #590
dmm wrote: post #584

Earlier quoted context omitted.

What they are discussing is simply an acceleration of a natural process: the carbonate-silicate cycle[1]. Silicate rocks are transformed into carbonate rocks through weathering. This captures CO2 from the atmosphere. When carbonate rocks are transformed back into silicates through metamorphosis or magmatism the CO2 is released back into the atmosphere. This definitely has the potentially for the long-term capture of…

The Carbonate Silicate cycle you linked also states: >These dissolved minerals are eventually carried by water to the ocean, where they are used by living organisms such as foraminifera, radiolarians, coccolithopores, and diatoms to create shells of CaCO3 (calcite) or SiO2 (opal) through the reactions Ca2+ (aq) + 2HCO3− (aq) → CaCO3(s) + CO2(g) + H2O(l) (for calcite precipitation) and SiO2(aq) → SiO2(s) (for opal pre…

Why would the CaCO3 return to carbonate after death ? In the past skeletons of diatoms dropped down to the ocean floors in huge layers which are now limestone rock.

Re: Carbon Removal Technologies

#604

Post by [deleted] »

49para wrote: post #578
wdewind wrote: post #448

Earlier quoted context omitted.

The problem with mob grazing (and really any kind of similar system) is that you cannot support nearly as many animals per sq ft. in comparison to more industrialized farming. Salatin's solution is to shift a major portion of the work force/economy into making sustainable food. It sounds amazing from a utopian standpoint but is a total fantasy.

Won't the rise of automation result in a lot of people without jobs ? They could start working on sustainable food. Sounds like a win / win.

[deleted]

Re: Carbon Removal Technologies

#605

Post by strainer »

notpg wrote: post #601
strainer wrote: post #596

Earlier quoted context omitted.

Grassfed does not necessarily lead to more methane production, it depends on the mix of grass and secondary vegetation, on the grain mix being compared to, and on potential supplements. https://prairiesoilsandcrops.ca/articles/volume-1-3-print.pd...

Just reading the article you provided and "Feeding high grain diets to cattle unequivocally lowers the formation of CH4 in the rumen." seems to disagree with what you're saying?

That isolated statement only loosely connects to the over reaching statement which I responded to: the performance of the high grain diet depends on the type of grain. In addition, there are complications.

From same section of the article it was picked from :

"While increased use of grains in ruminant diets reduces enteric CH4 emissions, there is concern that increased grain production may increase the use of fossil fuels for fertilizer, machinery, and transport, resulting in more greenhouse gas emissions. Grain feeding ignores the importance of ruminants in converting fibrous feeds, unsuitable for human consumption, to high-quality protein sources (i.e. milk and meat). Furthermore, high grain diets can negatively affect cow health due to acidosis. With escalating grain prices, the scope of further increasing the grain content of ruminant diets in Canada is limited"

Even ignoring CO2 cost, nutrition, grain availability and all other complications, what is required to show that grass fed diets necessarily lead to more methane output than alternatives - is a comprehensive study of the performance of all dietary options and supplements. I dont think that is setting too high a bar, to avoid arguing on sweeping generalization and loss of context.

Re: Carbon Removal Technologies

#606

Post by ForHackernews »

aurelwu wrote: post #557
ForHackernews wrote: post #155

Earlier quoted context omitted.

I thought the recent UN report was saying that we'd need more like a $5,000/ton tax at this late stage. Here's a right wing source: https://www.heritage.org/energy-economics/commentary/un-clim... > To accomplish such a feat, the new IPCC report proposes an energy tax of epic proportions. It claims that, to keep warming in check, by 2030 we’ll need to impose a tax of between $135 and $5,500 on every ton of carbon emit…

Those numbers are definitely inflated, even at current stage Direct Air Capture Technology is already at well below 1000 Dollar per metric tonne with an outlook to end up below 100 Dollar per tonne in ~20 years. [0] Not saying that DAC is the ideal approach but I find those numbers you mentioned to be very inplausible. [0] https://www.sciencemag.org/news/2018/06/cost-plunges-capturi...

I think the idea is that the tax would dis-incentivize emissions, so the cost of capture is irrelevant.

Re: Carbon Removal Technologies

#607

Post by Xixi »

yazaddaruvala wrote: post #429
aoner wrote: post #202

Earlier quoted context omitted.

Hi Gustaf, I read earlier that you are more interested in Direct Air Capture technologies than others. Do you have any specific reasons? I think another way we could look at things is finding "cheap" forms of carbon that would have otherwise been burned/left to rot and reprocess those into building materials.

I'm not Gustaf, but I'll try to answer this. The return on investment for a lot of Carbon capture/sequestering is not lucrative (or at least the business models are not yet apparent). The long term VC angle for air to fuel seems straight forward. - Mars alone will be a huge market for such technology. Driving a lot of demand 100-200 years out (if not a big market in 20-40 years). - Shanghai, et-al, need air filters.…

I don't see how you could make a "sail" boat powered by reclaimed fuel from air, as there is no fuel in the air. You will need a source of energy to convert the CO2 to fuel. In nature the most common (to my knowledge) CO2 -> fuel process is called photosynthesis, and is powered by the sun.

CO2 -> fuel consumes energy (that is stored in the fuel). Fuel -> CO2 releases it.

Re: Carbon Removal Technologies

#608

Post by ben_w »

ianai wrote: post #554
cbkeller wrote: post #432

Earlier quoted context omitted.

Geologist here. Can't speak to the economics, but there's no shortage of mineable olivine, mostly in areas where mantle lithosphere that was formerly below oceanic or island arc crust has been "obducted" on the continental crust and thrust up to the surface (the mantle is mostly olivine). These are called ophiolites, and they're not uncommon in places where you used to have a destructive plate boundary: https://en.wi…

Google says there’s 2.996×10^12 tons of carbon in the atmosphere. I’m guestimating we have about 1/3 of that which needs to be pulled out to correct for emissions to this point. Do we have access to that amount of olivine? Thank you so much for your comment! Edit-As to pricing, if olivine is a common byproduct of other activities and generally common in that sense then obtaining 1 ton of olivine is the cost to move i…

> I’m guestimating we have about 1/3 of that which needs to be pulled out to correct for emissions to this point.

For the moment, that’s a slight overestimate; we’re a little over 400ppm, and pre-Industrial levels were about 300ppm, so we “only” need to remove 1/4 (and we don’t really need to go back all the way to preindustrial levels, it was about 325ppm in 1970)

Re: Carbon Removal Technologies

#609

Post by strainer »

wdewind wrote: post #448
DTrejo wrote: post #444

Earlier quoted context omitted.

Salatin’s mob grazing creates soil. It is cheaper to raise them this way because you don’t need to buy corn feed. The cows digest grass well. They do not digest corn well, which means corn fed cows produce methane and get sick, and don’t build the soil (sequestering carbon). Definitely worth watching some YouTube videos and reading about it, it’s pretty fun and interesting.

The problem with mob grazing (and really any kind of similar system) is that you cannot support nearly as many animals per sq ft. in comparison to more industrialized farming. Salatin's solution is to shift a major portion of the work force/economy into making sustainable food. It sounds amazing from a utopian standpoint but is a total fantasy.

Mob grazing does not need more work, and it reportedly needs no fertilizer and less land, and it was noticed years ago - this is how it is clearly fantasy at this stage. The strategy would have transformed existing beef and dairy economics within years of discovery.

Re: Carbon Removal Technologies

#610

Post by ben_w »

aboodman wrote: post #418
drankula3 wrote: post #363

Earlier quoted context omitted.

And needlessly passive aggressive posts drive me nuts. Production will rise to meet supply, but that does not mean it will do so smoothly or easily. Perhaps accessible olivine is limited. Perhaps current extraction methods would be too expensive at scale. We just don't know.

Of you watch the video on the landing page they describe that olivine is a very common by-product of mining for other stuff. Currently the practice is to just pile it up, as it's worthless. So you don't even need to mine it (at least until demand scales way up) - just go to nearest mine and pick it up.

In much the same way, you can fuel a Diesel engine with a free waste product (used deep fat frying oil), which some people would even pay you to take away.

Only thing is, once a significant number of people started doing that, it generally stopped being free — people started charging money for it.

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