Launch HN: AirMyne (YC W22) – Capturing CO2 from air at industrial scale
Companies spent over $1B on CO2 offsets last year, sourced primarily from landowners and project aggregators claiming to protect forested lands. Over the past few years, interest in more permanent forms of CO2 removal have led to the pilot-scale commercialization of novel bio-oil/biochar/biomass, direct air capture, mineralization, and ocean processes, but these are not yet available with sufficient capacity to meet demand. There is no silver bullet, but we believe removing CO2 from air with an industrial chemical process offers the most realistic and scalable path forward.
Capturing and sequestering CO2 from air is a huge engineering challenge. The dilute concentration of CO2 in the atmosphere (~400ppm) means a system operating at 100% capture efficiency would still need to process 2500 tons of air to capture just 1 ton of CO2. Significant energy is then required to release CO2 from the capture medium. On top of that, compressing and injecting CO2 underground requires controlling for gas leakages, dry ice blockages, and the corrosive conditions created when concentrated CO2 comes in contact with trace water vapor.
Our approach goes back to the fundamentals of acid/base chemistry. CO2 acts as an acid and will bind to a base, whether in the liquid phase or on a solid surface. We have developed a process to bring air in contact with a base substrate that captures CO2 molecules while letting N2 and O2 molecules pass through. After energy is applied, CO2 is desorbed from the substrate for downstream treatment and compression. This reversible process allows for a single stage “air in, CO2 out” system where 1 ton of substrate could capture >1000 tons of CO2 over its useful lifetime.
In the lab, we have demonstrated this approach at a gram-level scale and believe the process offers favorable energy use, planned capex/opex costs, and process complexity compared to existing solutions. (We’d love to show you a video but can’t do that yet—the chemistry & physical embodiment of the system are areas where we’re developing core IP and that process still involves some secrecy at this stage.)
As we scale this process, we are initiating discussions with other companies who can help us inject captured CO2 deep underground so it can be sequestered for geologic time scales. Sequestration technologies have improved their compression and injection processes over the years, and an emerging regulatory landscape is starting to take shape to accelerate the deployment of CO2 injection wells and mineralization projects in the US, the EU, and around the world. We intend to colocate our CO2 capture near injection facilities to minimize transport logistics.
Sudip and I both come from industry. At Honeywell, Sudip invented and scaled the low-global-warming refrigerant 1234yf used in automotive air conditioning systems, as well as a variety of products used to make displays, computer chips, sensors, solar modules, and electrical components. I invented formulations at BASF now widely used in the manufacture of silicon carbide power electronics for EVs, solar inverters, and other high power electric devices. We bring a systems engineering perspective to the C02/climate problem—our focus is not only developing, but also derisking and scaling industrial systems/processes into a business case suitable for large industrial stakeholders.
Eliminating existing emissions is the most urgent and important challenge we face to keep the climate habitable, but removing CO2 from the atmosphere will likely be needed too. Tackling this problem head-on opens up other f...
197 comments
[ 5.0 ms ] story [ 262 ms ] threadDoes this use amines as well or is it a different chemical reaction?
As long as a) the total cost people are willing to pay for CO2 removal gives sufficient margins vs. the cost required to capture it, b) the end-to-end process actually removes substantially more CO2 than it emits, c) the resources allocated to pursue more CO2 removal makes sense vs. other uses (biased, but we think so), and d) the sequestration is done in a well-characterized & verifiable way, we think it makes sense.
Many companies & stakeholders are working right now to define in what contexts CO2 removal makes sense for them. We have LOIs from multiple companies who want access to our CO2 removal capacity as soon as it becomes available.
The CO2 captured from our process could be used for any number of applications if there is an economic/policy reason to pursue it. Fuels, fertilizers, and many other materials can use CO2 as a feedstock, and many startups are actively working on this problem from different angles. Startups are injecting atmospheric CO2 into concrete with great success. There is no reason we couldn't adjust our business model to divert CO2 captured with our process to these applications.
Our <$100/ton cost projection includes storage. PNNL has some great public resources, including on Youtube, that go into more detail the total cost of storage.
Can't comment on what chemistry we use, but amines are effective at capturing CO2 and have been used industrially for that purpose for decades.
If you'll achieve that then this has to be done. France has a CO2 emissions of about 5ton per capita per year (which is pretty low for an industrial nation). But if we get all industrial countries into that ballpark or even lower, then we could just invest another $500 per person each year and are at net zero.
We agree that eliminating CO2 emissions must be the primary & most urgent goal, while CO2 removal solutions like ours can be developed in parallel to meet immediate early market demand & prepare (e.g. get costs down, validate & improve the tech, get the regulations set up) for future deployment.
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.
However at this stage, we are more focused on scaling our capture process so it can be integrated to injection/sequestration later on at a pilot plant scale.
Why not just do post-combustion capture if it's cheaper and more effective?
(Would love for an entrepreneur to come up with a way to find a market solution to this matching problem -- AirMyne might want to bid to be the technology platform on which such a CO2 capture system is built!)
and we're still arguing about whether fission is good in the year of our lord 2022
1) Market. Early buyers of CO2 credits are primarily looking to get very clean accounting of who gets credit for the CO2 removed, and will pay a premium for anyone who can do it. If a buyer (say, a software company) pays for a polluting chemical factory or power plant to capture some of its emissions, it requires complex multi-party contracts & the incentives between the parties are often conflicting. That being said, point-source CO2 removal is absolutely needed & a huge opportunity/problem and more work is needed from a technology/policy side.
2) The "extreme user" case. If we give 100% focus to solving the more challenging problem of removing CO2 from air, we may gain learnings & knowledge that will translate to an improved point-source capture process, whether from an energy/efficiency/cost perspective.
Injecting it underground is just turning waste into waste, which depends entirely on regulatory controls to become sustainable; though of course, developing an efficient process for capture is a hugely important step.
I'm curious what the latest developments are on finding a use case for captured CO2?
I wondered about the scale here. In 2020 we emitted 34.81 billion tons of CO2 from fossil fuels[1]. Now that's much more than what I can lift, or even imagine. So let's say we want to build Pyramid of Giza sized monuments out of that. The Pyramid of Giza weigh about 5.75 million tons[2].
That means that if we want to soak all the yearly emission into monuments we need to find place for about 6000 Pyramid of Giza sized ones. That's a lot of monuments to go around. And then next year we repeat again. I'm not sure this will scale.
> Injecting it underground is just turning waste into waste, [...]
Yes? That's where the carbon was stored for hundreds of millions of years and it was fine there until one day humans figured out a way to get it out and spread it into the atmosphere. The problem is not that we have a moral objection to CO2 on principle. The problem is that it's screwing up the atmosphere.
1: https://ourworldindata.org/co2-emissions 2: https://weightofstuff.com/how-much-does-the-pyramid-of-giza-...
For now, we are focusing on CO2 removal from air to align with market/"extreme user" angles, as described in some comments above.
Is this the most energy intensive part of the process? What kind of energy do you apply? (heat?)
Whenever you're past the secrecy stage, I'd love to see a blog post or video to learn more about your approach.
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!
Also could the process be adapted to use sources of waste heat like from nuclear power, solar or geothermal?
The process could potentially use waste heat & that is something we are thinking about as we think about plant design, potential locations, and partners.
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.
I would love to see that comparison. Incl. the aspect that the plant does not need to be repaired, multiplies on its own, etc.
Deep underground sequestration is the only viable strategy if your goal is total CO2 reduction in the atmosphere.
That is untrue. So untrue it seems like a deliberate lie.
The only solution is to stop pumping CO2 in into the atmosphere.
There are mitigations. Building huge machines to sequester relatively small amounts of carbon in underground chambers is probably a mitigation. It seems to me that there are better ways and these sorts of ideas are not worth the opportunity cost.
Of course, we are going to see far more than a 1°C increase which is why it is worth doing.
Forests only sequester carbon as they grow. After that they are carbon neutral. You end up with land that cannot be used for any economic purpose. (The creatures and plants that live in it have a value too, but that is not part of this argument).
After that, at some point, in a year, ten years, a hundred years, the forest burns. And all the carbon is released.
A pointless waste of time. We do it because we are obsessed with things we can count (one tree, two trees....) and fixated on the short term.
There is a better way: https://www.sciencedirect.com/science/article/abs/pii/S00167...
Increase depth of top soil all over our agricultural land. It increases productivity and sequesters carbon. But it has no profit centre and is hard to measure, and given our "big man" capitalist culture that is the problem.
We really must stop producing CO2. That is the only answer that does not steal the future from our children
I will be paraphrasing the science articles I have read lately...
Planting new trees on bare land does not work to capture CO2. So if you deforest an area and then re-plant, you put a lot of extra CO2 into the atmosphere. Like 30% of the trees you harvest go into durable things (like houses) and the rest will decompose and release its carbon. After you leave the ground bare, it starts spewing CO2 from the soil. This is a major carbon source. New trees you plant will EVENTUALLY soak up more CO2, but canopy closure needs to happen before that can happen. Since the young trees are planted with considerable spacing, the soil CO2 source outpaces the tree CO2 sink for many years before the balance shifts.
Mature forests throughout history probably did tend to be carbon neutral on average, yes. This is ignoring ecological changes... like... maybe forest conversion to other landscapes and fires were balanced by healthy forest uptake. I digress.
These are not normal times, and CO2 concentration is very high. Because of that, old-growth or mature forests may be significant sinks of CO2. The best strategy for us to draw down more with forests is to leave as much mature forest untouched as we can.
https://en.wikipedia.org/wiki/Biochar
and
https://en.wikipedia.org/wiki/Bioenergy_with_carbon_capture_...
"So the kelp will sink to the ocean bottom in the sediment, and become, essentially, part of the ocean floor..."
1.https://www.npr.org/2021/03/01/970670565/run-the-oil-industr...
Maybe this is a naive question: but why not bury plants? We got into this mess by digging up long-buried plants, so why not literally reverse the process? With intentional effort, maybe this could be a viable solution? (Probably not -- but I'm curious why.)
Possible. Practical. Increases productivity.
Of course it's not enough to balance human emissions. Sequestering carbon in fields, as pointed out, is a win-win solution which may do a large part in canceling emissions.
Most likely, industrial/engineered solutions and nature-based/bio-based/ocean-based solutions will need several years to evaluate which paths are most viable. We wish everyone luck in this challenge for the world's sake!
(I'm asking because most past carbon capture projects are actually enhanced oil recovery projects, and the accounting they do for co2 avoided is... sometimes really creative. From what I'm aware Climeworks is not directly collaborating with the fossil fuel industry and does not do EOR, which I think is why they have a relatively good reputation.)
https://en.wikipedia.org/wiki/Carbon_dioxide_flooding
Down in Texas there are places you can drill and get CO2 just like you drill for methane, oil, helium, etc. Since the late 1970s this has been a profitable business without anyone being paid for CO2 disposal.
At our early stage, we are focused on developing our capture technology & thinking carefully how to best partner with folks who can do sequestration.
The fossil fuel companies know how to compress & inject gases underground at huge industrial scale. They, as well as the oilfield services companies that support them, have expertise that is difficult to access otherwise: they know how to build & monitor wells, find & characterize saline aquifers & other geologic formations where CO2 can be stored, and so on. Coming from our industrial background, we know that their expertise in these areas is not something we want to categorically ignore. Applications with the EPA for Class VI (non-EOR) wells are in the pipeline process around the US, and similar injection-only wells are being built/planned in other parts of the world and we are keeping a close eye on those developments. In addition, mineralization is a possible path too.
I wish we could give a clearer answer. No doubt it's a complex question & we are thinking about it carefully in our planning.
Would love thoughts.
https://www.studioroosegaarde.net/project/smog-free-project
That's not to say a decentralized system can't be done. If someone can do it & it costs less than us, that's good for the world. But coming from years in the chemical manufacturing world, we believe that humans have learned a lot, especially over the past 2-3 centuries, how to build huge chemical production facilities that make (relatively) efficient use of power & resources to process ton-scale quantities of materials. We have experience in bulk-scale chemical facilities for other chemical processes, and know that when they work, they can work really well. So we believe that bulk industrial scale is the fastest/cheapest way for CO2 removal from air in a way that can be deployed fast enough & in an economically-sustainable way to meet existing/forecast demand for voluntary CO2 credits & eventually to tip the needle through large-scale deployment.
A lot of technologies to solve waste problems have been invented and launched, but very few get used at a large scale.
Some questions:
What do you see as the biggest roadblocks to adoption of your product? What makes AirMyne more attractive than the existing options? https://time.com/6125303/direct-air-carbon-capture-infrastru...
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.
Subterranean mineralization is a fascinating path too and may help with some leakage concerns.
We believe that CaCO3 can work in some small-scale contexts but it takes up a lot of volume/mass when done at industrial scale -- finding somewhere to put all the CaCO3 is a challenge, as is moving it there and avoiding negative impacts that come with it. Someone else in this thread made a good comment about this too.
And they're not burning it they're roasting it by putting in lots of energy to naturally drive off the CO2 content as a gas due to the high heat. Leaving you with CaO which is the chemical representation for lime.
The fly in the ointment is that the limestone is already the ideally captured form of carbon itself.
Limestone is still being heavily removed from the ground too and tonnes are being roasted into the lime that the concrete industry needs. Rather than just leaving it in the ground where it has been safely sequestered by nature for zillions of years.
More buildings could just be built directly from blocks of the limestone itself, maybe that would have significant environmental impact.
Yes, that nice white lime sure is an ideal active alkaline CO2 absorber because it naturally wants to turn back into limestone again by itself, like other alkalies do not. So the lime eventually does absorb CO2 back from the atmosphere as the cement hardens.
But each tonne of lime can only capture the same amount of carbon that was given off from the original limestone to begin with, and that was at great expense of energy.
If this could be clean energy the best you would do would be carbon neutral, unless the CO2 released from roasting the limestone could be captured at the source.
But what are you going to absorb it with if not more lime?
Plus you've got to first get it out of the ground and then back in to the ground afterward.
Thinking about things going in & out of the ground, elsewhere in the messages there is a good estimate of the density that pure compressed CO2 would have if pumped directly into supercritical storage underground. And that's about the same density as the original crude oil had so that's basically both a barrel-for-barrel and tonne-for-tonne equivalence. That means a barrel of (liquified, pressurized) CO2 needs to be put back underground for every barrel of oil removed. And a tonne of oil is basically 3 barrels but a tonne of CO2 is contained in 1600 tonnes of atmospheric air so you need to process 44000000 cubic feet of air to get one tonne of CO2 since gases are light when they're not under pressure and/or chilled/cryogenic storage. That's enough air to fill 150 Goodyear blimps. Just to get enough liquid CO2 to fill a pressure container about the size of 3 oil barrels, if your air-removal process is 100 percent efficient. Then you can break even.
If you want to truly cut back on atmospheric CO2 levels you're going to have to remove more than one barrel of CO2 for every barrel of oil produced and gas leaked worldwide.
Interestingly, many oil fields which are considered "expired" (because their production has declined below positive economic returns) still contain sizable percentages of the original oil beyond that which can be readily recovered under natural pressure or continued pumping. Still right there in the pore space of the oil-bearing rock.
These formations are also the ones that can be expected to have a barrel of storage space for every barrel of oil that had been removed, so it might be a good place to put equal quantities of CO2.
Oil companies have already injected CO2 into a central well of a once-productive field, and it uses up a lot of CO2 but the outer wells then start producing better for a while so additional salable oil is a (by)product of the procedure. But since the napkin math says it's a barrel-for-barrel equivalence they have to be able to get the CO2 way cheaper per barrel than they can sell the oil for. Or even an oil company can't afford it and they're getting more oil in the process. I'm not so sure how anybody else would fare.
As far as pressurized CO2 escaping from oil formations and oil field equipment, I don't think it would be any easier to eliminate all leaks forever than for methane, where progress is being made but we are far from there already.
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.
https://agupubs.onlinelibrary.wiley.com/doi/10.1002/2015WR01...
Capturing CO2 from a power plant, biofuel factory, oil refinery, petrochemical plant or other point source and disposing of it underground is a developed technology. Very little of that is happening because the financial incentives aren't there and the financial incentives that do exist go to carbon sequestration schemes which are low-cost, low-quality and generally not measurable (pay us $ and we won't cut down these trees... for now, let's crush some rocks and apply sand to the beach and hope for the best, ...)
With aquifer injection you can measure the gas going in but there are also questions such as: how long does the CO2 stay there? do you have seismic problems?
This scheme is similar to aquifer injection but is more secure at the expense of requiring unusual rock formations and 25 tons of water for every ton of CO2 captured.
https://en.wikipedia.org/wiki/Carbfix
I think it gets way too much press but assuming energy is available you can build a direct air capture in a place where you have reactive rocks and water.
THe question is how many tons does this plan to produce over what period?
Feel so powerless.
Only dollars too fund(sustain) suppression....
And that’s just the people who want to get rich while saving the world, not charities like Greenpeace, or government interventions like Feed-In Tariffs and fuel taxes.
--
What ~~would be the balance btwn the effort for climate change, vs,~~
What the heck are we doing?
We keep talk of CO2 offsets, and Sequestering...
WE FUCKING NEVER SPEAK OF PROCESS OPTIMIAZATION WHICH REDUCE CO2 T BEGIN WITH??? !!!
Band-aid much bitch. WTF?!
So? I in this context that is a plus not a minus!
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Serious question.
-- musk. (and ppl like Thiel cooncerned with eternal life (Rocks, Roths, etc)....
Okay, I only responded because of the Baader–Meinhof phenomenon. I watched a video about lovelock and Gaia Hypothesis yesterday.
And this is completely ignoring the CO2 cost of building the rocket.
THAT is a viable reason for them
We should just put this entire debate to bed, shouldn't we?
JUST ONE MORE THING
Go fuck yourself
How so? The simple fact that natural gas and oil still exists, when it comes from 100 million year old biomass, proves beyond a shadow of doubt that geological sequestration holds its integrity at geological timescales.
We have also been injecting CO2 at a rate of 1 million tonnes per year at the Sleipner field in the North Sea since 1996, and extensive 3D timelapse seismography shows the CO2 is permanently trapped.
Think about that - we have been demonstrating CO2 storage at scale since before the launch of the first Palm Pilot.
Honestly, the storage part is a solved problem from the feasibility side. The remaining challenges are mainly cost optimization, across all of capture, transport and storage.
And the biggest hurdle is forcing businesses to actually pay for the currently externalized cost of CO2 emissions.
To sequester the world's carbon emissions, we would need to move and store <1% the volume per year.
And anyone in Europe can tell you that natural gas transfer and storage is far from a solved problem.
Europe is a great example of how we have the technology to transfer huge amounts of gas, and the challenges are largely politics and capital.
Nordstream #1 moves 60 billion m3 of gas 1,200 km and cost ~$10 billion
That being said, we try to bring a conservative approach to our scaleup plan. The most immediate challenge is demonstrating CO2 removal at the megaton scale (1 million tons per year) to validate the process and meet short-term demand for voluntary offsets.
Industrial CO2 also mostly comes not from the ground but from other industrial processes.
Those things I mentioned buy their CO2 on the market. I have no idea where it comes from.
plot showing the breakdown with some gov't sources. --> https://www.iea.org/reports/putting-co2-to-use
CO2 stored underground, at huge expense? What could possibly go wrong with that?
Other projects apply energy to turn the CO2 into liquid fuel. Of course that returns the CO2 to the atmosphere, but it'll be a long time before we electrify long-haul jets so it'd be great if their fuel were carbon-neutral.
https://www.osti.gov/servlets/purl/1390435 <-- a non-commercial study on this topic.
https://youtu.be/osXq-k84LpA?t=2177 <-- a webinar that addresses this topic
Thanks for this comment - the calculations I'd been doing in the GP comment and elsewhere where pretty darn depressing and this approach you're mentioning is very exciting in that it bypasses the fundamental storage volume problems most other sequestration methods face by leveraging the interstitial spaces inside existing rock volumes, and also exciting in that it leverages undersea rock formations for even lower impact. Thanks for pointing me to this.
For others interested in learning more you might hit [0] or [1].
[0]https://news.climate.columbia.edu/2020/02/19/solid-carbon-ma...
[1]https://www.nature.com/articles/s43017-019-0011-8
There are not many chemical reactions that 'fix' CO2. The compound is pretty low energy. Kind of a analogous to 'feed' bacteria with plastics.
The Swiss start-up Climeworks [1] has a business model built around actually already is in operational mode when it comes to pumping CO2 into the ground in Iceland.
[1] https://www.reuters.com/business/environment/worlds-largest-...
Please understand, this is not as simple as you think.
* > 1 Billion dollars
* > 5 Million MWhr
Assuming 200 Kg/MWhr of CO2 emissions produced by electrical generation (I believe the average carbon intensity in the USA is over 400 Kg/MWhr) the emissions produced (just for the electricity to do the extraction) is 1 Million Tons of CO2.
Thus, it looks like with the current estimates the process costs 1 Billion dollars and doesn't reduce CO2 at all. Like ethanol, I wonder if this process will be worth it in the end. I don't know what raw materials it requires and how much CO2 is generated in their extraction and production. It's possible that your belief that at industrial scale the CO2 intensity and dollar cost will go down, but are you even accounting for the CO2 cost of manufacturing the facility, transportation of raw materials, etc.
Coming from the chemical manufacturing world, we have (painful) experience modeling & planning for new processes & know that cost/energy models of new processes can only get us so far.
That being said, we see a path forward for our process at scale and are motivated to make it a reality.
A ton is a ton, regardless of phase (solid, liquid, gas, feathers)
If you compress it, it keeps the same weight (to any reasonable precision), but you won't get it into a solid.
https://en.wikipedia.org/wiki/Ideal_gas_law
I hope it won't be from fossil fuels.
"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."
This sounds very similar to how Verdox[0] is approaching the problem. What sets your approach apart?
[0] https://verdox.com/
[Patent US1783901A](https://patents.google.com/patent/US1783901A/en ) (1930-ish) shows the basic closed-loop configuration that most folks build from.
Gist is to sorb acid-gas (like CO2) into a basic-solvent (e.g., aqueous monoethanolamine), then heat it up to release the acid-gas. Then the regenerated-solvent can be reused.
Making the process closed-loop may've been more of a focus around 1930. Before that, I think there were some patents showing open-loop designs (this is, designs where the solvent isn't regenerated-and-reused).
Interesting, and of course worth noting that many geological events have done exactly this when calcium bearing rock (chemically basic) is exposed and weathered, capturing carbon as calcium carbonate. See, e.g. the hypothesis that the uplift of the Himalayas contributed to a past ice age[1].
One way to grasp the scale of the problem of sequestering our current level industrial emissions is to imagine assembling a calcium surface comparable to that of the Tibetan plateau. That's not to minimize the value of potential sequestration solutions here, which as you note will definitely need to be coupled with emissions reductions. Just that we need to, in effect "move mountains" to get this to work.
[1] https://pubs.geoscienceworld.org/gsa/geology/article-abstrac...
The wind turbine nacelle could be substantially cheaper than in the typical electrical generating turbine, instead coupling mechanically or hydraulically to the water pump.
Some people worry that this would saturate the deep ocean with CO2. A bit of calculation shows this is an idle concern: the shallow ocean is already being saturated with CO2, with immediately dire consequences, and there is overwhelmingly more deep ocean water than surface water. So long as atmospheric CO2 falls off over the coming century, there would no long-term problem.
Geoengineering that tackles the root problem, CO2, is fundamentally different from schemes that only (e.g.) try to block insolation. Other engineering is going on to tackle upstream CO2 emission, but we have a huge stock of CO2 already built up in the atmosphere that will need to be drawn down.
I don't know how the carbon credit economy works. I would welcome enlightenment.
I've heard deals with prices in the range of $0.5 to $5 per tonne CO2 equivalent. There's also a decentralized protocol that aims to move these credits onchain (https://toucan.earth/), their BCT (Base Carbon Tonne) token price is currently around $3.1.
As stated in the post, last year ~$1B worth of credits are sold. One McKinsey report expects it to be around $50B at 2030.
There are much more details of course, but these are the basics as I know.
So yeah maybe it's better for the planet but since it's harder to regulate it would be tricky to get funding to build that if the potential profit comes from the government intervening to set a price for the CO2 removal you are doing.
It doesn't cost any less to keep a wind turbine and pump still than to leave it running, so there will be no incentive to cheat.
We will need thousands of these things, all over the world. Maybe even millions.
That cooling would directly reduce current average earth temperatures, in addition to the CO2 impact on long term heating / cooling.
Maintaining a pipe, even one a half-mile long, is pretty cheap. (It has floats along its length, so it doesn't need to be especially strong.) Probably the biggest maintenance chore is keeping the intake from being fouled with barnacles, something most easily handled by replacing linings periodically.
Water at 40m depth has a different pressure than at the surface level. Pumping at the surface and releasing at depth will have significant water pressure difference.
(A quick Google later). At 40m, it's 5atm or roughly 75psi pressure.
(Another quick Google). Oil pipelines run at a higher order of magnitude as that, so it's doable but would return energy, increasing as you go deeper.
You do not need to get the water at the surface to 10, or 100, or 1000 atm. You just need a long pipe that goes all the way to the bottom.
Likewise for transporting water upward.
It sounds like a cool idea but is not really related to what AirMyne is trying to do! Lots of ideas are promising and people need to be working on all of them
The important difference is not how the CO2 is collected, or where it ends up. Ultimately, what matters is how much mass of CO2 is collected per unit cost, and how much CO2 is collected in total. I.e., how profitable is it, and how much difference does it really make? We need methods that can move CO2 out of the atmosphere by, ultimately, billions of tons per week.
If we did that for example in the East Australian Current north of Vanuatu, we might help out the Great Barrier Reef a little, moderating both the temperature and the acidity. It's like 3 birds with one stone.
I guess pumping up has the additional complexity of having the intake all the way down at 2KM, which is also where you'd need to do the maintenance. But maybe you could float up the entire pipe for maintenance.
Seems a similar idea has been proposed, but from a depth of a mere 40m: https://www.theguardian.com/environment/2017/apr/07/plan-col....
Where waves are available, the wind turbine might not be needed. Waves tend to happen mostly where water is shallow. Anyway, idea is that you have a big, floating, anchored fabric tube with rim held above mean surface level, that waves slop into. Once water is in, the only exit is way down deep. So more water slops in all the time, and moves down under the weight of what comes in after it.
Then, you need no wind turbine, no pumps, no moving parts at all; just anchors, floats, a surface frame, and a few thousand square yards of very tough fabric.
The tube doesn't need to go straight down. It could collect water in (relative) shallows and exhaust it some distance off, at cost of just more fabric.
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I also have no clue about the economics of carbon capture. Maybe ask David Roberts? He has always answered my emails. (Note he's currently on vacation.)
Roberts is my current primary source for climate and energy policy news. He definitely talks to all the right people, eg Saul Griffins.
Here's a sample of his articles which may be relevant to your question:
These uses of CO2 could cut emissions — and make trillions of dollars [2019] https://www.vox.com/energy-and-environment/2019/11/13/208395...
A simpler, more useful way to tax carbon [2020] https://www.vox.com/energy-and-environment/2020/8/17/2137073...
Volts podcast: Sen. Tina Smith on the promise of a Clean Electricity Payment Program [2021] https://www.volts.wtf/p/volts-podcast-sen-tina-smith-on-the
Volts podcast: Rebecca Dell on decarbonizing heavy industry [2022] https://www.volts.wtf/p/volts-podcast-rebecca-dell-on-decarb...