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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

#151

Post by namibj »

jsantos511 wrote: post #91
kensouris wrote: post #78

What about the energy balance? If your capture is exothermic you will warm up the cooling water and your client will not have enough cooling for their process. When you regenerate, do you need to add energy? How much CO2 is generated by the energy you need?. If you have to add heat to regenerate, how do you now cool the water back down to the temperature required by your client? Most industrial cooling systems use ca…

The energy balance is going to be critical, I agree! We are still working on finalizing all the inputs for this process, including regeneration amounts, amount of heat added, etc. Based on our early modeling, it seems the amount of heat generated from the capture will be negligible since the amount of CO2 moving through our system is much smaller than the amount of water available to provide cooling. Our chemicals ha…

Are you using sodium hydroxide for scrubbing, along with calcium (hydr)oxide for regenerating?

If so, remember you could branch out to indoor air scrubbing, as higher NaOH concentrations can balance the "humidifier" effect.

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

#153

Post by baq »

jaakl wrote: post #141
danans wrote: post #107

Earlier quoted context omitted.

> 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 co…

Most of your yearly 15 tons is emitted via specific exhaust pipes, where capture part is quite easy problem, even without these cooling towers. The big problem is what to do with all of it: there is no commercial use/market, especially if you want that to be climate friendly, ie not dumped to atmosphere quite soon anyway. We'd need to think of it as toxic waste, similar to nuclear one, to be stored forever undergroun…

for every 'can we afford it?' question you can also ask 'can we afford not to do it?' and in this case the answer is at the very least not simply 'no.'

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

#155

Post by acidburnNSA »

hannob wrote: post #148

So if I understand this correctly you are adding this tech to existing cooling towers? I don't see this answered on the page, but: what cooling towers do you have in mind? I don't have any statistics at hand, but my guess would be most cooling towers are coal power plants and other fossil fuel infrastructure. This seems problematic as you're creating an incentive to keep fossil fuel infrastructure. Also industrial he…

Ideally they'd go on low carbon cooling towers e.g. from nuclear plants.

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

#156

Post by sabas_ge »

ginko wrote: post #154

I wonder what it would take to reduce the captured CO2 to elemental carbon.

Something like https://en.wikipedia.org/wiki/Bosch_reaction ? I am also interested in knowing more, I know that Sabatier reaction is planned to be used in SpaceX Starship project..

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

#157

Post by WhompingWindows »

Thank you for working for our climate -- best of luck!

It seems you're after a more efficient method of collecting CO2, not a long-term storage method for CO2. I think the messaging may get muddled, people may believe you're attempting to lower atmospheric CO2, not just save some energy in CO2 production. To that end, how much CO2 would you actually be "preventing" from this action, and how does it compare to the top-ranked solutions needed on drawdown.org? When it comes to climate, I want the MOST EFFECTIVE solutions, and I don't know if this is low-hanging fruit relative to refrigeration management, diet, transportation, installing renewables, etc.

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

#159

Post by SamBam »

jsantos511 wrote: post #60
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/

Yeah, I was going to say, it hasn't been 385 since about 2008.

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

#160

Post by blaufast »

codecamper wrote: post #44

Have you heard about George Church's idea? He says it's possible to modify the dna of cyanobacteria so that they become immune to their natural predator: the cyanophage. Apparently cyanobacteria consume an incredible amount of CO2 every year, but then right away release it again after the cyanophage kills them. Seems like a potentially workable idea, but I have not heard him give the details anywhere. He is at MIT &…

Cyanobacteria cultivation is an old idea[1] and is limited by more than just phage. I did the math on carbon removal in a controlled environment somewhere like Nevada, and it could contribute to climate solutions. If Church is suggesting we release GMO cyanobacteria into the ocean, that is a whole separate category of idea, somewhere between Guam's Brown Tree Snakes and Ice Nine. If it succeeds, we will introduce a new kind of ocean trash - an organism with no predators. But phage is likely just mutate anyway. IDK how close you've been to Church or his orbit, but most of his ideas are mostly clickbait.

In the case this one isn't, the release of genetic modifications into the wild will be a debt our children have to pay, the way we are paying for our ancestors use of CO2.

https://www.frontiersin.org/articles/10.3389/fenvs.2018.0000...

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