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Direct air capture: our technology to capture CO₂

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Re: Direct air capture: our technology to capture CO₂

#101

Post by adammarples »

mchannon wrote: post #55
thx-2718 wrote: post #3

"Our plants require less land than other techniques. E.g., on a land area of 0.42 acres, our Orca plant can remove 4,000 tons of CO₂ from the air every year, which is almost 1,000 times more effective than trees. The same land would host around 220 trees with an estimated capacity of 22kg each" How much land, in solar panels for example, is required to power this? Also what's the carbon waste that this generates? Is…

1000 kWh/ton (found it on google): 166 kW/ton in a sunny place: 1000 square meters/ton in a sunny place: 4 million square meters = ~1000 acres of PV to power. One unit. Yeah, that’s going to happen. /s “We’re too ashamed of our energy requirements to post them on our page and are well aware they’re dooming this technology until cold fusion comes out” is what I read between the lines on their fluff page.

Their plant is in Iceland and runs on geothermal

Re: Direct air capture: our technology to capture CO₂

#102

Post by maigret »

jackmott42 wrote: post #71
yodelshady wrote: post #30

Earlier quoted context omitted.

It's such an easy, relevant question to ask that it boggles the mind that investors don't have their own engineers to ask it. I know you're money people not tech, but how do you know you're not being ripped off if you can't check figures that basic? Anyway, apparently 3 MWh/tonne is a not-unrealistic claim, so they're only demanding 1.5 MW (on average, though if solar-powered it would make sense to oversize) and a km…

Welcome to planet Earth. If you can do napkin math, and bother to do it, you can be an extremely successful in engineering domains, because almost everyone else is completely useless.

Napkin math is an underestimated skill indeed.

Re: Direct air capture: our technology to capture CO₂

#103

Post by photochemsyn »

shafyy wrote: post #59

Climate scientist David Ho has a good thread on CDR: https://mastodon.world/@davidho/109511745525784891 It's hard for people to visualize removing tons or billions of tons of #carbon #dioxide (CO₂). I propose we talked about CO₂ #removal (CDR) like a #time #machine (e.g., this machine will take us back 5 minutes). For example: Q: How far back in time does planting 100 million #trees take us? A: If one mature tree tak…

Even a complete cessation of fossil fuel use won't change the current trajectory much, it'll just mean the slope (rate of warming) doesn't get much steeper. This is due to the long lag (much of it related to slow ocean equilibration to atmospheric forcing), as well as the permafrost emissions:

> "Given current rates of warming, an estimated 130-160 billion tons of permafrost carbon, could be released in the form of greenhouse gases—primarily carbon dioxide but with an important warming contribution from methane—during this century. Thus, emissions from thawing permafrost, in total equivalent to 61-75 ppm atmospheric carbon dioxide, could be similar to other Jluxes from other environmental changes, such as deforestation, but far less than fossil fuel emissions. New plant growth is expected to offset only ~20% of this carbon release, but this offset could help to delay impacts on climate."

- "Climate change and the permafrost carbon feedback", Schur et al. (2015) Nature

Humans will have to adapt to a new climate regime, by necessity. It's not going to be very pretty.

Re: Direct air capture: our technology to capture CO₂

#104

Post by aftbit »

idlewords wrote: post #83

A similar technology (bed of amines that absorbs CO2 from ambient air) is being tested on the International Space Station, so it's worth reviewing how this stuff breaks: 1. Pipes and bearings clog up or corrode. 2. Trace contaminants irreversibly react with the sorbent material. 3. Stuff in the beds shifts around in unexpected ways, aided by the heat cycling. 4. The problem gets harder the more dilute the gas is. The…

Wow I didn't realize that submarines and the ISS had such a high level of CO2. I feel noticeably worse when CO2 is above 2000ppm in my house. I've always wanted to have an artificial CO2 scrubber for when the windows are closed, but energetically I would probably be better off opening the windows and heating or cooling the air to compensate. Do submariners and astronauts have impacts to their cognitive abilities from this elevated rate?

Re: Direct air capture: our technology to capture CO₂

#105

Post by vlovich123 »

14 wrote: post #85
vlovich123 wrote: post #66

Earlier quoted context omitted.

Humans emit about 35 billion tons a year according to the reports which comes out to emit 100 million tons per day.

Then we will need to see these machines scale up over time like we see solar doing now. I hope one day industry will be required to match their carbon capture with devices like this to their carbon output. Perhaps someone will make a solar farm in tandem with these co2 capture devices with the fans from these devices cooling the solar panels as solar panels work more efficiently at cooler times (1). 1: https://www.so…

It’s not enough to get to zero emissions. We’re well past the point where we need to get to negative. And afaik these machines can’t scale to even a fraction of the way to net 0 unless we start building out fission/break through with fusion.

Think of it this way. It’s more energy intensive to capture carbon than it was to generate the electricity from that carbon. The amount of energy required to make this work requires you to generate roughly the same order of magnitude of energy as has been emitted through the burning of fossil fuels since the beginning.

I’m a big fission supporter but I doubt even fission could get to the cost scaling needed to generate all this energy effectively. Even fusion might struggle since we don’t actually yet know what the unit economics of it will be.

We might get lucky and figure out a way where recapturing carbon is net cheaper energy than it generated but I doubt it as that feels like it would be very close to a perpetual motion machine scenario.

Re: Direct air capture: our technology to capture CO₂

#106

Post by marcosdumay »

clnq wrote: post #99
fwlr wrote: post #22

Their subscription page is currently offering a rate of about $1.35 USD per kg of CO2 removed, and they promise to complete your order within 6 years. It’s nice to have some hard numbers on end-stage or “gold standard” CO2 offset (no doubt there are cheaper carbon credit options but this directly solves the hardest problem, CO2 that’s diffused into the atmosphere.

It would take around £12k a year to offset my carbon footprint in the UK, where it is below average. That's a significant part of my take-home salary. I could spend maybe £1-2k a year, especially given the futility of this (I would be one of the 0.00...01% of people doing this, large industries will continue to increase pollution, there is no political will for meaningful measures to reduce emissions). There really i…

> Can some company do this carbon filtering at the source more cost-effectively?

If you have some centralized source like that, you should invest on replacing it with something that doesn't emit CO2. It's always a better deal.

Carbon capture is for sources where you just can't plug something like this.

Re: Direct air capture: our technology to capture CO₂

#107

Post by tlb »

shafyy wrote: post #59

Climate scientist David Ho has a good thread on CDR: https://mastodon.world/@davidho/109511745525784891 It's hard for people to visualize removing tons or billions of tons of #carbon #dioxide (CO₂). I propose we talked about CO₂ #removal (CDR) like a #time #machine (e.g., this machine will take us back 5 minutes). For example: Q: How far back in time does planting 100 million #trees take us? A: If one mature tree tak…

That must reflect a suboptimal choice of tree. Sequoias, for instance, can capture 400 kg / yr for a few hundred years.

Re: Direct air capture: our technology to capture CO₂

#108

Post by adrianN »

Retric wrote: post #98
specialist wrote: post #88

Earlier quoted context omitted.

Time machine is neat metaphor. Thanks for sharing. -- Net Zero is not enough. We must do Net Negative, a much bigger project than Net Zero. The goal is CO2 350ppm, or lower. Today is 417ppm. It will be >600ppm in 2050, our current global Net Zero deadline. There is no either-or. We need all the solutions. To stop and then reverse emissions: solar, wind, geothermal, nukes (old and much more new), storage, transmission…

The earth naturally sequesters carbon on its own, we are simply vastly outpacing that process. So no we don’t need artificial carbon sequestration to hit even preindustrial levels again. Carbon sequestration is unfortunately more of a scam than a practical process. Without actual discouraging the burning of fossil fuels people aren’t going to simply stop on their own and if we can’t even get that far nobody is willin…

Natural sequestration is a very slow process. If we want to avoid tipping points we shouldn’t rely on it alone.

Re: Direct air capture: our technology to capture CO₂

#109

Post by lillecarl »

somedude895 wrote: post #84
kmeisthax wrote: post #6

Lots of information about land usage, not so much about power usage beyond "it'll run on renewables". I imagine their cost benefit analysis boils down to "governments will pay for it to not die", which sounds rather optimistic.

And then wouldn't all that renewable energy production better be used to replace fossil fuel production? Maybe once we've replaced all possible CO2 emitting power generation it would make sense to start building out more to power these things?

This is the scheduling problem, you can't schedule all renewables, so using them inefficiently is better than not at all.

Re: Direct air capture: our technology to capture CO₂

#110

Post by marcosdumay »

foverzar wrote: post #69

Every time I see technology like this, I wonder why there so much effort and publicity in capturing carbon from thin air, but no one seems to be interested in capturing carbon directly out of exhaust pipe?

Because what you should do with a large static exhaust pipe is to turn it off.

And after you do that, you will still need capture from air.

But on the company's side, it's probably because the companies that own large static exhaust pipes aren't interested on helping cleaning anything up.

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