Launch HN: AirMyne (YC W22) – Capturing CO2 from air at industrial scale • Hacker News Board

Re: Launch HN: AirMyne (YC W22) – Capturing CO2 from air at industrial scale

#31

Post by oliwary » Thu, Mar 17, 2022, 4:46 PM UTC

InvaderFizz wrote: post #29

sabertoothed wrote: post #23

I would love to see a page on your website where you compare yourselves (in a fair and transparent way) to the best plant that does the same thing. I am not knowledgeable in the field. But there will be some algae or mangroves that get CO2 out of the air. I would love to see that comparison. Incl. the aspect that the plant does not need to be repaired, multiplies on its own, etc.

The problem with plant based sequestration is that it is a net neutral proposition unless you can bury the plants. All the talk about forests being so great(and they are, just not as carbon sinks) ignores the complete lifecycle, which is only as negative as the sustained volume of the forest, assuming you started from just dirt. If that forest ever burns, it's all back in the atmosphere again.

What about building houses and furniture with the wood?

Re: Launch HN: AirMyne (YC W22) – Capturing CO2 from air at industrial scale

#32

Post by markcyffka » Thu, Mar 17, 2022, 4:51 PM UTC

UnpossibleJim wrote: post #19

While I applaud your needed technologies, I was curious if you had any plans to foster relationships/partnerships with any "clean" (read cleaner) energy solutions to power your energy needs for carbon capture and sequestration?

Right now, there is an ongoing discussion between a huge variety of stakeholders -- CO2 removal startups/companies, academics, regulators, 3rd-party verification standard-setting bodies, etc. -- to figure out what kind of life cycle analyses (LCAs) are required at the planning stages, and what verification frameworks will be needed post-capture/sequestration stages, to ensure that CO2 removal from air is removing more CO2 than it emits.

In many of these discussions, and in the studies/analyses which drive them, moving to cleaner sources of energy makes a lot more sense given the total CO2 removed vs. CO2 produced/embodied in the system.

It is a complicated question and it really depends on what temperatures your process requires, where in the world you decide to build your removal system, if cleaner energy is available there (& at what cost), how you need to compress/store/transport the CO2 so it can be injected or converted into something else, and so on. Cleaner energy like geothermal, solar, nuclear, hydro, etc. are not always co-located near the best injection sites and there are questions of whether DAC is the best usage for cleaner energy resources vs. for general grid deployment.

To make a very long story short, cleaner energy makes CO2 removal a lot more sensible to pursue at scale, so that is where we are aiming as we think about the long-term system design.

Re: Launch HN: AirMyne (YC W22) – Capturing CO2 from air at industrial scale

#33

Post by InvaderFizz » Thu, Mar 17, 2022, 4:51 PM UTC

oliwary wrote: post #31

InvaderFizz wrote: post #29

Earlier quoted context omitted.

The problem with plant based sequestration is that it is a net neutral proposition unless you can bury the plants. All the talk about forests being so great(and they are, just not as carbon sinks) ignores the complete lifecycle, which is only as negative as the sustained volume of the forest, assuming you started from just dirt. If that forest ever burns, it's all back in the atmosphere again.

What about building houses and furniture with the wood?

That is typically only sequestering the carbon for 20-50 years. In the end, the house is torn down, or the furniture burned. Very little lasts for more then a century, and basically nothing lasts for more than a millennia.

Deep underground sequestration is the only viable strategy if your goal is total CO2 reduction in the atmosphere.

Re: Launch HN: AirMyne (YC W22) – Capturing CO2 from air at industrial scale

#34

Post by multiplegeorges » Thu, Mar 17, 2022, 4:52 PM UTC

Is there a risk that sequestered CO2 gets released later by accident?

Have you looked into sequestering it into calcium carbonate? It's extremely stable and harmless to the environment. Just sink it to the bottom of the ocean with all the other sea shells.

Re: Launch HN: AirMyne (YC W22) – Capturing CO2 from air at industrial scale

#35

Post by yodon » Thu, Mar 17, 2022, 4:53 PM UTC

I want to be excited about this, but it's capturing CO2 as CO2 gas, not sequestering CO2 in a form that keeps it out of the atmosphere.

If you pay a lot of money in process and power to pull CO2 out of the atmosphere or out of exhaust gases and then use it in chemical processes other than ones which sink the carbon into long lasting solid, liquid, or oceanic absorption form you're just burning money and power to make yourself feel good, you aren't actually denting the global climate change problem because all that CO2 will just end up back in the atmosphere once it's been used in the industrial processes.

You also can't use storage of gaseous (or liquid) CO2 as a way to sequester climatically meaningful amounts of CO2. We've added around 600 billion tons of CO2 to that atmosphere since 2000. If we want to use sequestration to roll back the changes we've done to the atmosphere, we almost certainly need to sequester at least that much, if not more out of the atmosphere. Do a quick calculation on how big a set of storage tanks you need to hold that amount of gaseous or liquid CO2, and compare that volume to the volume of a mountain (or mountain range) near you. Then think about maintaining those tanks in perpetuity and you'll see why you have to get the CO2 stashed in solid or room temperature stable liquid form.

I'm by no means critical or dismissive of this tech, it sounds great, but we're still a long way from pulling off the sequestration that's actually needed at the scale that's needed.

Re: Launch HN: AirMyne (YC W22) – Capturing CO2 from air at industrial scale

#36

Post by mikeyouse » Thu, Mar 17, 2022, 4:53 PM UTC

oliwary wrote: post #31

InvaderFizz wrote: post #29

Earlier quoted context omitted.

The problem with plant based sequestration is that it is a net neutral proposition unless you can bury the plants. All the talk about forests being so great(and they are, just not as carbon sinks) ignores the complete lifecycle, which is only as negative as the sustained volume of the forest, assuming you started from just dirt. If that forest ever burns, it's all back in the atmosphere again.

What about building houses and furniture with the wood?

It's not a terrible solution, but you need specific trees of specific thicknesses for it to be possible at all (and these aren't always the same trees best suited for rapid growth). Selecting the most carbon-intensive plants and then turning them into biochar is probably better for long-term sequestration.

Re: Launch HN: AirMyne (YC W22) – Capturing CO2 from air at industrial scale

#37

Post by markcyffka » Thu, Mar 17, 2022, 5:03 PM UTC

chinathrow wrote: post #28

Whats the difference in your method to the one used by Climeworks?

We'd rather not speak to anyone else's technology, except to say that we support anyone working on CO2 removal & have only gratitude & respect to pioneers in this ecosystem, including Climeworks, who paved the way for CO2 removal to be a part of the larger climate conversation.

Re: Launch HN: AirMyne (YC W22) – Capturing CO2 from air at industrial scale

#38

Post by markcyffka » Thu, Mar 17, 2022, 5:06 PM UTC

roldie wrote: post #16

Congrats on the launch and good luck! Whenever you're past the secrecy stage, I'd love to see a blog post or video to learn more about your approach.

We trained at big engineering companies so secrecy is our M.O.! For better or worse...

We can & must show more to the community as we get to pilot scale. We know that people/society needs to see more physical examples CO2 removal to realize that it's possible. And it looks cool too!

Re: Launch HN: AirMyne (YC W22) – Capturing CO2 from air at industrial scale

#39

Post by arbuge » Thu, Mar 17, 2022, 5:07 PM UTC

InvaderFizz wrote: post #29

sabertoothed wrote: post #23

I would love to see a page on your website where you compare yourselves (in a fair and transparent way) to the best plant that does the same thing. I am not knowledgeable in the field. But there will be some algae or mangroves that get CO2 out of the air. I would love to see that comparison. Incl. the aspect that the plant does not need to be repaired, multiplies on its own, etc.

The problem with plant based sequestration is that it is a net neutral proposition unless you can bury the plants. All the talk about forests being so great(and they are, just not as carbon sinks) ignores the complete lifecycle, which is only as negative as the sustained volume of the forest, assuming you started from just dirt. If that forest ever burns, it's all back in the atmosphere again.

Of course there is always the possibility that things could burn but forests that burn do grow back eventually. Plant-based sequestration should not be written off. A planet covered by X% of forest vs Y% where X%>Y% has more sequestered carbon. If that X% is long-term stable, i.e. if the forests are preserved and curated on a long-term basis, then so is that carbon. Forests are also an enjoyable natural environment for humans, which is an added bonus.

Re: Launch HN: AirMyne (YC W22) – Capturing CO2 from air at industrial scale

#40

Post by Robotbeat » Thu, Mar 17, 2022, 5:09 PM UTC

markcyffka wrote: post #12

boringg wrote: post #6

Whats the energy cost per ton of CO2 removed?

Right now, it's >5MWh/ton using lab scale equipment. At 1 million ton per year scale, we expect closer to 1-2MWh/ton.

To put that in perspective, pure graphite or carbon (basically equivalent to anthracite) releases about 2.5 MWh of heat per ton of CO2 produced.

Pure methane (if fully combusted) releases about 5.6 MWh of heat her ton of CO2 emitted.

Oil is somewhere in between.

In terms of electrical or mechanical (ie useful, low-entropy) energy produced per tonne of CO2 emitted, HHV efficiency typically 25-50%, so between 0.625 and 1.25 MWh/tonne of CO2 per tonne of coal and 1.4-2.8MWh/tonneCO2 for methane.