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Launch HN: Noya (YC W21) – Direct air capture of CO2 using cooling towers

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Re: Launch HN: Noya (YC W21) – Direct air capture of CO2 using cooling towers

#101

Post by ip26 »

toomuchtodo wrote: post #4

If you're not injecting the CO2 underground in a stable form, how does this reverse climate change? It sounds like it's simply a cheaper option in some circumstances for sourcing CO2 from the air (compared to traditional solutions by Airgas). Not to take away from your efforts! I think this is a fine improvement to CO2 process needs if you can replace more expensive air extraction techniques, but it doesn't contribut…

Every new technology or company needs that first customer, first revenue stream, to get off the ground. Selling CO2 to beverage companies is the DAC "MVP". Sequestration is an independent problem that can be coupled to DAC later down the road when both are ramped.

Re: Launch HN: Noya (YC W21) – Direct air capture of CO2 using cooling towers

#103

Post by cma »

networkimprov wrote: post #75
jsantos511 wrote: post #27

Earlier quoted context omitted.

The US is home to over 2M cooling towers: https://www.nsf.org/news/road-map-improve-response-legionnai... Using the numbers we've calculated with our first partner plant, we're expecting to be able to capture 0.5-1 ton/day with their 25 ton cooling tower. This is a very small tower - for perspective, UCSF operates a 5,400 ton cooling tower to operate their small electricity co-generation plant, and cooling towers at…

What percent of current US CO2 production is 730M tons?

~5 billion metric tons is what we emit.

Re: Launch HN: Noya (YC W21) – Direct air capture of CO2 using cooling towers

#104

Post by joe_the_user »

So, this link gives CO2 emitted into the atmosphere by humans in 2019 as weighing as 43.1 * 10^12 metric tonnes - 43.1 billion tons [1].

Now, the third of you links, describing your plant, talks about capturing one metric tone of CO2 per years. If you could scale this plant up to 1000 times in the capturing ability, you would then need one million of these plants scatter across the globe to capture a billion metric tonnes (about 2% of human emissions say).

I'm doubtful the commercial demand for CO2 would pay or that governments would be willing to pay for this (not to mention the need for energy).

Which is to say you seem describe atom sized drop in an ocean-sized bucket. Is any reason to think this could meaningfully "reverse climate change"?

[1] https://www.theworldcounts.com/challenges/climate-change/glo...

Re: Launch HN: Noya (YC W21) – Direct air capture of CO2 using cooling towers

#105

Post by imtringued »

Fiahil wrote: post #25

How does this compare to the most ancient carbon capture tech: Trees ? I know this sounds boring, but a single $M would allow to plant as much trees and they will capture carbon from the atmosphere, without any maintenance, for decades.

I don't know about trees but bamboo sounds like a good candidate.

Re: Launch HN: Noya (YC W21) – Direct air capture of CO2 using cooling towers

#106

Post by ip26 »

breck wrote: post #70
jsantos511 wrote: post #39

Earlier quoted context omitted.

To put it plainly: we need more trees. However, trees cannot get us all the way there. Trees are great for drawing down atmospheric carbon emissions in the short-term, but when trees decompose, they just release that carbon back into the atmosphere. Additionally, the landmass and water needed to sustain all these trees will require another solution to get all of the way to where we need to be with carbon removal.

Since its towers we're talking about, what about an ivy/clonal plant? And can't you just bury the dead trees? I also don't understand what the equation is. Is it something like this: CarbonCaptureRateToStopGlobalWarming = growTreesPlantsAndBuryDeadOnes(...params) + newTech(...params) If so, what is the order of term 1 and the order of term 2? It seems to me that at the end of the day only 1 of these terms will matter…

Nobody has figured out a roadmap to get to done using only term 1. But we know it will help, and make other things better in the meantime, so it's always worth doing. Meanwhile, term 2 is unsolved but probably the only way to get back to 350ppm.

Re: Launch HN: Noya (YC W21) – Direct air capture of CO2 using cooling towers

#107

Post by danans »

abhv wrote: post #49

Quick math: Density of air at sea level: 1225 g/m^3 C02: 0.0383% by volume (383 ppmv) corresponds to 0.0582% by weight. Ergo, 1m^3 of air has 0.713 g of C02 in it. Ergo pulling 1 metric ton (10^6 grams) of C02 per day requires processing AT LEAST : 10^6/ .713 = 1.4m m^3 of air per day or 16 m^3 of air per second! (That would assume 100% capture) I was skeptical that 1 cooling tower generates this much flow, but the e…

> Ergo pulling 1 metric ton (10^6 grams) of C02 per day

The CO2 footprint per capita in the United States is 15 metric tons [1], so at 300M population, that's 4.5e9 metric tons of CO2 per year.

At 1 metric ton CO2 removed per day per tower, we would need 4.5e9/365 = 12.3M such cooling towers. Even if the efficiency increased 2 orders of magnitude it is still not enough, and I doubt there is a need for even 123,000 cooling towers.

None of this is to say that it shouldn't be pursued as a business opportunity to sell CO2 to commercial customers.

But realistically, given the scale of the CO2 problem, we still need to dramatically reduce the amount of CO2 we are emitting per capita as a primary measure, with any carbon capture as secondary.

1. https://data.worldbank.org/indicator/EN.ATM.CO2E.PC?location...

Re: Launch HN: Noya (YC W21) – Direct air capture of CO2 using cooling towers

#108

Post by ip26 »

monopoledance wrote: post #99
jsantos511 wrote: post #84

Earlier quoted context omitted.

The short answer is that we absolutely need more trees than we currently have, but trees alone won't be able to get us there. Trees are great at capturing CO2 from the sky, but they suffer from an impermanence issue. Trees capture CO2 for the duration of their lifespan, but when they die, they decompose and release that captured CO2 back into the atmosphere. They also require dedicated use of large swaths of land to…

I don't think this is the complete picture. In an intact old forest, a lot of bio-matter doesn't decompose in time, but rather gets buried in the anaerobic zone. In a healthy forest the first few centimeter soil are so biologically active just about 30cm down there is very little oxygen left to house much life. That's also why murder victims don't decompose very fast, when the murderer buried them deep in forest soil…

I think it's pretty easy to see, though, that restoring the world's forests to their condition circa 1700 will not get us to 1700 CO2 levels, as we have added some 1.5T tons of fossil carbon to the mix since then.

Re: Launch HN: Noya (YC W21) – Direct air capture of CO2 using cooling towers

#109

Post by ip26 »

umvi wrote: post #59

We definitely need more innovation like this. Pressurized CO2 canisters may not be the most efficient (from a density standpoint) way to capture carbon, since you are capturing oxygen too and it's being stored as a gas, but hey, it's a start. We can iterate from there.

It's a multi-step process. Collect CO2. Convert it to something else. Store it.

This startup is currently focused on improving the first step. You have to collect the CO2 before you can do something with it.

Re: Launch HN: Noya (YC W21) – Direct air capture of CO2 using cooling towers

#110

Post by avernon »

carbonguy wrote: post #100
avernon wrote: post #28

I love this. I started laughing when I read the description. I laughed because a Harvard physicist (funded by people like Bill Gates) had the same idea to use cooling towers for their DAC project in Carbon Engineering (linked in your post). But as you say, it is still expensive. They are bragging that their design took hundred of man years! And then you two guys come in with the idea that in hindsight seems completel…

I'm no engineer; that said, I think you're being slightly unfair to the Carbon Engineering folks, as paper [3] that OP linked states that CE's design reflects "reflects roughly 100 person-years of development." That doesn't strike me as outrageous in this context (30 people working for ~40 months?), although I'll grant I don't have a ton of perspective on industrial process development. That said, OP's idea does have…

Since you are piggybacking on their system, you'd save on peripheral equipment costs and operating costs, too. The subsystems surrounding these cooling water systems are immense. They need river/lake access for water, giant pumps to feed the makeup water into the system, giant fans running all the time, and even larger pumps to circulate the cooling water after. There is a lot of nickel and dime complexity/cost in things like water purification. I'd be shocked if it only knocked 5% of the cost off.

Plus many facilities have surplus low pressure steam you could use to regenerate your fluid.

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