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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

#51

Post by sulam »

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…

The more economic CO2 capture techniques I've heard of that actually do result in sequestrable product rely on having high concentrations of the stuff, much much higher than is available in the atmosphere. Having a method to concentrate CO2 could be a great initial step in being able to do more with it.

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

#52

Post by ajb »

jsantos511 wrote: post #35
quantified wrote: post #31

What are the environmental effects of the chemical mix? How do you reclaim the chemicals from the cooling water?

Unlike many traditional carbon capture chemicals, the one we are using are both non-volatile and stable when they come into contact with air and heat. This means that our chemicals will not float out of the top of a cooling tower with evaporating water and will instead stay in the water. After carbon capture happens in the cooling tower, we run the stream through a regeneration process to release the captured CO2 and…

Hmm good so far. Presumably there will be at least some losses, since the system is open to the atmosphere. So you'll need good evidence for how safe the chemicals are. (I appreciate you may not want to tell us what they are yet)

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

#55

Post by mattmaroon »

jsantos511 wrote: post #48
mattmaroon wrote: post #37

Earlier quoted context omitted.

Yeah it would seem that if someone buys a ton of CO2 from you, then that’s just one more ton some ethanol production facility vents into the air instead of capturing and selling right? Are you saying that your method of producing a ton of CO2 uses less energy than theirs?

In the short-term, it seems very likely that if ethanol plants do not sell that ton of CO2, it will end up back in the atmosphere. In the long-run, we have the opportunity to clean those emissions up with either new technologies that can produce ethanol without huge emissions (of which many people are working on) and/or regulations requiring carbon capture at ethanol plants. But, we have to break the reliance on that…

Yeah I mean, clearly removing CO2 from the environment (provided were not burning fossil fuels to do it) can’t be bad. For now it seems like you’re just shuffling the source of the problem, but i I see what you mean about ethanol sans-CO2. Is that a realistic thing in the near term?

If CO2 is all just a byproduct (I.e. nobody is producing it just to sell it) then it would seem that whatever source of it consumes the least energy from fossil fuels is the best from an environmental standpoint right?

So I guess my question is how does your solution stack up to current recapture in that regard?

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

#56

Post by [deleted] »

jsantos511 wrote: post #45
hahahahe wrote: post #18

Just a very noob question here. When carbon is released into the atmosphere where and how does it disperse? Can we expect it to gradually concentrate in lower elevations or in certain geographical traps?

Carbon is dispersed from the atmosphere wherever it's created. This could be the smokestack of a power plant, a tailpipe of a car, or any other source of emissions. That CO2 floats up into the air and mingles with all the other gases in the atmosphere. Areas that are more highly concentrated with CO2 than others will "push" their CO2 into lesser-concentrated areas, driving up the concentration everywhere over a long-…

[deleted]

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

#57

Post by pletsch »

jsantos511 wrote: post #27
pletsch wrote: post #17

How much CO2 are you actually pulling out of the air? I've read a bit about other carbon capture companies and Carbon Eng. is claiming 1M tons/year with the new facility they're building.

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…

That's great. The market for C02 is already there and cooling towers exist everywhere. I have a gut feeling this could be licensed to the large players for their new builds, even if the co2 is just used onsite.

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

#58

Post by jsantos511 »

lopuhin wrote: post #19

How large is the CO2 market relative to the amount of CO2 currently injected into the atmosphere?

The US currently consumes ~64M tons of CO2 / year: https://www.iea.org/reports/putting-co2-to-use

We need to remove somewhere between 100B-1T tons of CO2 from the air to get back to safe, non-planet-warming levels: https://nanransohoff.com/A-mental-model-for-combating-climat...

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

#59

Post by umvi »

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.

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

#60

Post by jsantos511 »

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…

We had a similar observation and related feelings — cooling towers move, quite literally, tons of air every day.

One suggestion I'd make to the math above: the concentration of CO2 in the air is a bit higher, at 415ppm per Scripps UCSD: https://www.co2.earth/

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