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Carbon Removal Technologies

carbon.ycombinator.com

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Re: Carbon Removal Technologies

#611

Post by Retric »

Symmetry wrote: post #165
Retric wrote: post #91

Earlier quoted context omitted.

The problem is you now need some actual structure rather than just some thin sheets / inflatable structure or whatever. Further applying even small amounts of force across huge sheets adds up while as you say it's acting like a solar sail. That is to say it's clearly still possible, just not as cheap as people are assuming.

IKAROS handled that by spinning very slowly to remain rigid with centrifugal force. To be practical you really can't have one single structure but a swarm of medium sized shades would work much better.

If by medium size your thinking ~1km^2 then sure. But, much smaller than that you you start talking about billions of these things. Keeping them properly aligned and not shading each other would be a non trivial challenge.

Re: Carbon Removal Technologies

#612

Post by eanzenberg »

spookthesunset wrote: post #529
eanzenberg wrote: post #408

Earlier quoted context omitted.

How is this not fear-mongering? Most people will be fine with a 5deg C global increase.

Maybe people, yes, in the short term. But everything that people depend on.... not so much. I mean, yeah we'd live but you an kiss coral reefs goodbye, glaciers, etc... It would be a rather shitty place to live.

Why though? Honestly, do you and 99% of the global population depend on glaciers and coral reefs?

Re: Carbon Removal Technologies

#613

Post by philipkglass »

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…

As btilly has mentioned a few times, ocean acidification is a major problem because atmospheric CO2 has risen so quickly. It takes a few thousand years for the atmosphere, the upper portion of the ocean, and the deep ocean to reach equilibrium. There is an especially elevated CO2 concentration and corresponding lowered pH in the upper layers because there hasn't been time to reach equilibrium with the larger volumes of water in the deep ocean. These upper layers of the ocean, sadly, are also where the vast majority of ocean life and photosynthetic activity exist.

Adding alkalinity to the oceans via accelerated silicate weathering can protect sea life against acidification. More alkalinity in the ocean also increases its absorption capacity for CO2, which reduces warming feedback effects caused by radiative forcing from CO2 in the atmosphere. The ocean contains ~60x as much inorganic carbon as the pre-industrial atmosphere; to draw down the content of the present atmosphere to pre-industrial levels, it would require increasing the dissolved inorganic carbon content of the oceans by less than 1%. Converting some of it to solid carbonate minerals is a nice-to-have but not especially critical, because average residence time of dissolved inorganic carbon is about 200,000 years, which will take us well beyond the age of fossil fuels.

https://www.soest.hawaii.edu/oceanography/faculty/zeebe_file...

Re: Carbon Removal Technologies

#614

Post by Eddh »

strainer wrote: post #591
dereke wrote: post #252

I've been watching waay too many youtube videos about reforestation, agriculture and land management recently and I think I've learned a little from it (links at the end). We no longer have the number of massive herds of animals that used to roam the plains/savannahs grazing, pooing and to a lesser extent escaping from predators. This has meant that the grasslands are no longer trampled on and "fertilised". This has…

I came across those videos before and noticed the main speaker has been giving talks for many years claiming he has transformed the fertility and productivity of multiple cattle farms in the course of research, by simply increasing cattle density and intensity. Alas if there were truth to the idea, Allan Savory would not need to promote it - he could own or have franchised thousands of farms by now. The purported enh…

The doubts about the technique seems warranted. On the other hand there is a simple reason why it might be true : if large herds destroyed the herbs on which these herds depend on, they would die off. So from an evolutionary point of view, it makes a lot of sense for large herds to fertilize soil. They NEED grass to thrive.

Re: Carbon Removal Technologies

#615

Post by markvdb »

According to the World Bank[0], the US produces 75% more CO² per $1000 of economic output than the EU.

The US should be able to reduce that inefficiency delta to just over 5% by cutting CO² emissions by 40% without any impact on luxury whatsoever. This alone would cut worldwide CO² emissions by about 5.73%.

[0] https://data.worldbank.org/indicator/EN.ATM.CO2E.KD.GD

Re: Carbon Removal Technologies

#616

Post by Pfhreak »

ISL wrote: post #108
gustaf wrote: post #72

Earlier quoted context omitted.

This is Gustaf from YC. I wrote the first Carbon Removal RFS. Planting tree is actually a great carbon removal technology. Unfortunately most forest owners in the world don't know or don't have incentive to care the about the carbon impact the forest have on the climate. Biggest reason forests are taken down is to grow cattle for beef. If you are working on a startup to reverse this we'd like to fund it too

If you'd like to fund trees, one could start buying land and start protecting trees. Spending that money on intensive lobbying and forest advocacy in rapidly-deforesting countries could have an impact, too. The trick, of course, is that neither of these techniques compound for the individual nor a startup. They are pure charity for the planet.

I'm seriously considering doing this myself. I've got some money set aside, and a smallish group (~20) people who are interested in contributing time, smaller amounts, etc. I'm no tech billionaire, but there's definitely areas where I could buy a few dozen acres of land.

I've been researching what's involved in reforesting, and it looks like a ton of work and a non-trivial cost. And maybe not the most efficient dollar / CO2 ratio, but also something that has the nice side effect of having a living forest around. (And also the side effect of providing exercise, access to the outdoors, etc.)

Re: Carbon Removal Technologies

#617

Post by littlestymaar »

matznerd wrote: post #230
btilly wrote: post #59

I would strongly suggest investigating the claims of http://www.innovationconcepts.eu/res/literatuurSchuiling/oli... that after mining, milling, and then being spread in the ocean, olivine rocks weather quickly and take out CO2. The estimated costs of large scale CO2 sequestration this way are surprisingly reasonable, and the technology is already available. Also the various ocean technologies are going to run into t…

I am working on a non-profit that is utilizing Schuiling's research and is actually getting this project done. We are scouting beaches right now for a "wiggle" tank, which is a sort of see-saw like device where we can gather data to affirm the real world dissolution rate. The chemistry, however, is sound that each 1 ton of olivine will sequester 1.25 tons of carbon. By the end of 2019 we hope to have our first olivin…

> The chemistry, however, is sound that each 1 ton of olivine will sequester 1.25 tons of carbon.

But what's the total CO2 cost of the olivine (extraction, processing and transport to the sea) ?

Re: Carbon Removal Technologies

#618

Post by ianai »

ben_w wrote: post #608
ianai wrote: post #554

Earlier quoted context omitted.

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)

With 20/ton of olivine it’s still around a 20 trillion dollar industry (just that cost alone)!

Re: Carbon Removal Technologies

#619

Post by nanomonkey »

jasonlaramburu wrote: post #268
nanomonkey wrote: post #221

Earlier quoted context omitted.

Tilling the soil actually releases quite a bit of CO2, some of the best practices are "no till" methods. But to your point, biochar retorts can and should be used at the source of the biomass, instead of burning fossil fuels to transport the biomass to a dedicated facility. Many small scale gasifier generators are designed to do just that. The problem with all solid fuels is that material handling is difficult (you n…

How can you get biochar into the soil without tilling?

Layering biochar mixed with compost on top of existing soil, and/or putting other biomass on top of that (Lasagne gardening, or no-till farming). The bugs and worms in the soil will move it around.

You can also drop it in when you plant (digging or double digging).

Re: Carbon Removal Technologies

#620

Post by gnopgnip »

joe_the_user wrote: post #179
philipkglass wrote: post #116

Earlier quoted context omitted.

To stay below 2 degrees of warming via CO2 curtailment alone, serious curtailment would have had to start a generation ago. I wish that we had acted with urgency then, but we didn't. Now we need curtailment and active interventions.

Indeed, The problem is that, given we're failing the straightforward task of curtailment even now, what are the chances that we can successfully achieve curtailment and sequestering in the required time-frame? Curtailment is a large task but we know what to do. Sequestering would also be a large task but what to do is uncertain. Curtailment so far has been a corrupt circus with "pledges" and other indirect inducement…

If we assume that global emissions will continue to grow at the current rate, or increase exponentially, the situation appears more dire than it really is. Renewable energy is getting cheaper every year, and fossil fuels are getting more expensive. Some sources of c02 fixation are more efficient when the c02 levels in the air are higher. Also as energy gets to be cheaper overall, the cost of sequestering goes down.
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