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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

#111

Post by criddell »

ping_pong wrote: post #81
simonebrunozzi wrote: post #54

Might be a dumb question, but: how can this be possibly cheaper than planting trees?

This is exactly my question as well. There's no way it's cheaper than planting trees and is probably orders of magnitude less efficient. And the plants itself must be producing an enormous amount of waste of pollution itself.

> There's no way it's cheaper than planting trees and is probably orders of magnitude less efficient.

Do your cost and efficiency calculation include the opportunity cost of letting land sit "idle"?

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

#112

Post by jsantos511 »

joe_the_user wrote: post #104

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 t…

Amazingly well thought out analysis - thank you. Completely agree that we will need a lot of shots on goal and many operations pulling carbon out of the air to deal with the size of this problem.

Our first commercial plant is estimated to capture ~1 ton CO2 / day, and that is with a very small tower. If all 2M towers in the US were the same size as our smallest one, we could capture 730M tons of CO2 / year, but we know that is a conservative assumption because many cooling towers are larger than the one we're starting with.

For example, one of the larger plants we've talked to runs a cooling tower that can capture ~44,000 tons of CO2 / year. This plant is a small power generation plant attached to a university, but let's assume it represents the cooling towers of all power plants.

There are 23,000 power plants in the US. Assuming they all have a cooling tower capable of capturing 44,000 tons of CO2 / year and all the rest of the cooling towers in the US are of the small size I mentioned above, our annual capture amount grows to:

[23,000 power plant towers * 44,000 tons/tower] + [1.9 other towers * 365 tons/tower] = 1.7B tons of CO2 captured / year with cooling towers.

Our estimate will get closer to the truth as we continue to understand the range of cooling tower sizes available on the market.

It's worth saying: for humans to meaningfully reverse climate change, we need many groups of people taking many shots on goal for us to be successful. I believe Noya has a critical technology that will play an important role in solving this problem, and I'm excited to be joined by many other amazing founders with fantastic technologies in this adventure.

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

#115

Post by semi-extrinsic »

jsantos511 wrote: post #50
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 help…

Interesting stuff. Curious to see what kind of solvents you're looking at, and whether you will need to think about mitigating aerosol or nitramine emissions.

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

#116

Post by jsantos511 »

danans wrote: post #107
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 co…

Couldn't agree with you more - the less we emit, the less critical the need for carbon removal technologies becomes.

We have two levers for reversing climate change: the first is reducing emissions, and the second is remove carbon from the atmosphere. Most of the pathways in the most recent UN climate report incorporate some amount of carbon removal to maintain global temperature rise below 1.5°C [1].

Humans have been hard at work for a while on our first lever, and we need many shots on goal with the second lever to give ourselves a chance at success.

[1]: https://www.ipcc.ch/sr15/chapter/chapter-4/

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

#117

Post by jsantos511 »

sulam wrote: post #51
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.

Absolutely right. Many carbon capture systems that are installed on top of smokestacks have much higher concentrations of CO2 than the air does (~300x higher concentrations in smokestacks). Henry's Law states that as partial pressure of a gas goes up, its solubility in a given liquid also goes up [1]. So, if you have a smokestack with a higher concentration of CO2 available than what you can get in air, it's going to be easier to capture the same amount of CO2 bc more CO2 will want to dissolve in the liquid that it's dissolving in.

There are some cool ways that people are working on to concentrate CO2 using membranes, metal organic frameworks, and other things - we'd love to someday incorporate something like this at the front end of our process!

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

#119

Post by jsantos511 »

elihu wrote: post #95
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.…

> 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. I thought that most ethanol is made from fermentation of corn, sugar, or whatever, and the carbon in that process came from the atmosphere originally. So, environmentally whether you make CO2 as a byproduct of ethanol production from CO2-absorbing crops or yo…

Great question - the carbon cycle definitely needs to be thought about in this scenario.

The missing link here is in total embodied emissions that go into production of corn. There's data available to help piece together a comparison [1, 2], and I'd love to work through this and get back to you with what I find. At a high-level, CO2 production from corn isn't net-neutral because the production of a corn, and then ethanol from that corn, is a fairly carbon-intensive process in terms of the energy it requires. Our process doesn't require most of the transportation corn does, and since the cooling tower is already operating, we don't have to incur any additional costs to capture the CO2. Our main costs are in the energy required for regeneration, and depending on the facility we're at, we may even get that for free in the form of waste heat/steam.

If you want to send me an email at josh [at] noyalabs.com, we can talk more about this there!

[1]: https://www.attisbiofuels.com/by-products/carbon-dioxide

[2]: https://watermark.silverchair.com/55-7-593.pdf?token=AQECAHi...

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

#120

Post by fernly »

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…

What is required is for a third party -- government or quasi-governmental agency -- to create a market by offering to purchase CO2 and sequester it. This would incentivize conversion of cooling towers. The offered price need not be as high as present users of CO2 pay, but merely high enough to prospectively amortize capture equipment over a reasonable time.
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