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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

#41

Post by jsantos511 »

VBprogrammer wrote: post #34

Using existing cooling towers to capture atmospheric CO2 seems like a much better idea than using energy to otherwise pump tonnes of air through a process. However, I can't help wonder whether it is better than capturing the exhaust emissions (primarily CO2 and H20) directly from the exhaust gasses, before they are released to the atmosphere.

There are two equally-needed levers we have to reverse climate change: the first is reducing current emissions, and the second is removing carbon from the atmosphere.

Removing emissions from smokestacks is critical to ensuring we can stop dumping waste into the sky, but we are at the point now where we need scalable, low-cost processes to pull carbon out of the atmosphere.

So, we need to definitely do what you're suggesting and capture all emissions from as many smokestacks as possible until we've fully transitioned to a clean grid. And, we also need to begin pulling CO2 out of the atmosphere.

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

#42

Post by woeirua »

How do you prevent scale build up, corrosion, etc from the chemicals that you're introducing into the water? For the most part, these towers probably aren't designed to deal with sustained high concentrations of some of these chemicals. If you can solve that problem, then I think you'll make it. If you can't then this will be DOA if you have to replace a lot of the hardware every X years.

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

#44

Post by codecamper »

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 & so are some of you guys... go talk with him! Maybe it could be used inside your towers as a way to more efficiently capture the co2?

Thanks for doing what you all are doing btw. We desperately need a solution.

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

#45

Post by jsantos511 »

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-enough period of time.

Drawdown works in the opposite way. By reducing the concentration in a single area, the global concentration would work to equilibrate, so more CO2 would "fill the void", and if more drawdown keeps happening, than more CO2 will keep equilibrating and filling voids, and more capture will happen.

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

#46

Post by woeirua »

VBprogrammer wrote: post #34

Using existing cooling towers to capture atmospheric CO2 seems like a much better idea than using energy to otherwise pump tonnes of air through a process. However, I can't help wonder whether it is better than capturing the exhaust emissions (primarily CO2 and H20) directly from the exhaust gasses, before they are released to the atmosphere.

DAC will be needed for the foreseeable future because there are some applications still where hydrocarbons are just unbeatable. In particular, large-scale marine and air transportation are just not feasible yet with anything other than some kind of hydrocarbon based fuel. That might not be the case forever, but it is for now. Eventually the goal will be to use DAC to synthesize hydrocarbon based fuels, thereby making them completely carbon neutral.

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

#47

Post by VBprogrammer »

jsantos511 wrote: post #41
VBprogrammer wrote: post #34

Using existing cooling towers to capture atmospheric CO2 seems like a much better idea than using energy to otherwise pump tonnes of air through a process. However, I can't help wonder whether it is better than capturing the exhaust emissions (primarily CO2 and H20) directly from the exhaust gasses, before they are released to the atmosphere.

There are two equally-needed levers we have to reverse climate change: the first is reducing current emissions, and the second is removing carbon from the atmosphere. Removing emissions from smokestacks is critical to ensuring we can stop dumping waste into the sky, but we are at the point now where we need scalable, low-cost processes to pull carbon out of the atmosphere. So, we need to definitely do what you're sug…

Thanks for taking the time to reply. I'm still not convinced that pulling atmospheric carbon out of the air makes sense until practically all smokestack emissions are captured at source. Something like putting the heating on while all the windows are open.

I wish you guys luck though, hopefully you can carve out a niche market which will mean carbon capture technologies are ready when the time comes.

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

#48

Post by jsantos511 »

mattmaroon wrote: post #37
jsantos511 wrote: post #13

Earlier quoted context omitted.

Great observation - somewhere between most-to-all of the CO2 that goes into beer, food production, etc ends up back in the atmosphere. Our initial model is the first key step towards the additional solutions we're designing to remove carbon from the atmosphere. The use of CO2 that is sourced from the atmosphere is better from an environmental perspective than the use of CO2 sourced from offshoots of an ethanol plant.…

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 method of production for the CO2 industry to help push all of that along. If companies are still getting their CO2 as a waste product, it may make regulation or incentives for new tech harder in the future. Just like EV's are getting power from the grid which is, in some places, still heavily reliant on fossil fuels, switching to EV's is breaking the need for fossil fuels in the transportation itself. We need to do the same for the CO2 industry.

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

#49

Post by abhv »

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 example in [1] suggests 17*10^6 ft^3/minute, or roughly 8000 m^3/sec.

Thus, as long as your capture chemical has 2% efficiency, it seems reasonable.

[1] https://www.power-eng.com/emissions/cooling-tower-heat-trans...

[EDITED after I detected an error in my math]

The amazing observation for me is that evaporative cooling towers process A LOT OF AIR per second.

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

#50

Post by jsantos511 »

woeirua wrote: post #42

How do you prevent scale build up, corrosion, etc from the chemicals that you're introducing into the water? For the most part, these towers probably aren't designed to deal with sustained high concentrations of some of these chemicals. If you can solve that problem, then I think you'll make it. If you can't then this will be DOA if you have to replace a lot of the hardware every X years.

De-risking all of these questions is currently one of our top priorities. We have an understanding of a handful of materials that are compatible with our system right now, and we are working to expand that list - and, just as valuably, remove items from that list.

Our chemist is leading these efforts, and she's got a ton of experience from getting her PhD/postdoc work at Yale's Center for Green Chemistry that is helping us properly vet these items out.

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