(disclaimer: I work in a Climate&Energy research group)

Ignoring the perverse incentive problem...

... enhanced weathering only works under certain conditions. Randomly spreading some olivine around at a specific GPS location does not effectively sequester CO2 on a useful timescale, for example.

Olivine also needs water, and the reaction is very slow, so almost all olivine proposals end up dumping the material in the shallow ocean (or grinding it small enough, say <2um, so that it stays in the mix layer before it fully reacts with CO2). Grinding energy is not linear, so a bunch of 100um rock (easy to produce) requires a lot less energy than a bunch of 2um rock. Vespa gets around this (they claim) by sticking the rock in the wave/tidal zone to break it apart naturally, and keep it from sinking out of the mix layer.

There are also issues with this from a biological standpoint (e.g. olivine contains some amount of nickel and cadmium), so doing this a gigaton scale would require a lot of research before incentivizing it.

TLDR, there are things one could do on land that might work, but not what is proposed.

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Long story short, I can't see a carbon coin being super successful if it is overly prescriptive on the method of CO2 capture, unless it gets very very lucky and happens to pick the right one.

Since the proposal already requires an auditing methodology (which is basically all the proposal really is, if I am reading it right), it may as well drop the exact technology being audited. At that point, it mimics a normal carbon market, but with printed money, so not clear how it's going to get traction over a fiat currency.

> so not clear how it's going to get traction over a fiat currency.

Everything else in your post was great, but there's certainly a precedent for even obviously unworkable ideas attracting much investment in the crypto space. Having something that could be beneficial is already way better than many crypto launches.

It was not meant as critical, just that it's unclear to me.

Unlike mining traditional crypto currencies, a carbon coin would require a large amount of capital equipment up front before mining. Bootstrapping without fiat capital would be an extra wrinkle.

I’m curious, what is currently the most promising carbon capture methodology that’s actually scalable? Already in use or ready to use, so we can exclude research projects with no path to mega-scale

There are only a few that are truly scalable and plausible. A lot of investment today is going into the low hanging fruit (afforestation, methane capture, etc). These are cheap (<$15/ton), but they cap out at a couple of Gt-CO2/yr equivalent.

BECCS isn't really scalable past a certain point, either, which leaves direct air capture and enhanced weathering.

Enhanced weathering is basically moving around alkalinity, which the CO2+water (carbonates) will neutralize. There are other ways of doing this besides dumping olivine rock into the sea (which gives you a very large surface area to absorb co2), though dumping rock is very inexpensive (probably less than $20/ton, modulo grind size and bio toxicity issues).

If humans disappeared today, the CO2 would revert back to pre-industrial levels predominantly through the ocean. The ocean is a large sponge for CO2, and it will stay in equilibrium with the atmosphere. As it turns over (~5000 years), it brings the extra CO2 down to depth, where it reacts with sediment. Extra CO2 will initially raise the carbonate compensation depth, reacting slopes of marine snow with the extra CO2 (kind of like snow melting) fairly quickly (on a geologic timescale). If/when that is exhausted, the ocean floor (which in places is covered with basalt and other material that will neutralize CO2) will (very very) slowly eat the rest of the CO2. As the carbonates drop in the ocean, the ocean will start to absorb more CO2 from the atmosphere. The ppm will drop slowly, until it hits the biosphere equilibrium (marine cycle, etc) of ~280ppm.

One scalable way (personal disclaimer, one of my research areas) to do carbon capture is to just speed up this process. There is no reason CO2 has to react with basalt, it can just as easily react with NaOH or some other source of alkalinity, which can be minutes instead of millennia. In fact, some direct air capture proposals (long ago) were just waterfalls of fine droplets with NaOH embedded as a sorbent.

So, long story short, if you can create alkalinity, you can easily turn that into sequestered CO2. Literally throwing an antacid tablet into the ocean sequesters CO2. Depending on the method of creation (e.g. chloralkali process), you may also have to dispose of an equal amount of acid, but that can be injected underground (e.g. poured out onto a bunch of olivine). Doing it all on land is a little trickier, as the ocean has some nice surface area and mixing ... but a large pond with a vertical firehose of high PH solution may be effective, though it starts to bleed over into the definition of DAC at some point and eats more power.

> TLDR, there are things one could do on land that might work, but not what is proposed.

I'm curious what these might be.

If the blockchain is immutable how do you reverse transactions if there's no monopoly on force in order to force the transaction?

Say I have 1 ton of carbon captured, I am paid 1 coin and I "prove" that I captured 1 ton. Secretly, the mechanism of my capture is temporary and I realize not only the 1 ton, but an additional ton as it costed me energy to make this scheme work. What are you gonna do?

Another, more likely example is that I say I have 1 ton captured, EnergyCorp has Bob audit me, I tell Bob, you approve of my fraudulent capture notice and I'll give you 10% of the profits. Bob agrees, I am paid my 1 coin. I give Bob 0.1 of the coin. We both win. Later Bob is found to have participated in the conspiracy. What are you gonna do?

You, the smart reader are reading this and think - OK fine, we'll build a way to confirm capture without anyone else being involved. Well, I point to scenario 1. What're ya gonna do? The post basically assumes trusted auditors, which is fine, but why even do blockchain?

Blockchain cannot beat reality.

For what it's worth, both scenarios apply to traditional fiat, but at least in that scenario punitive damages apply and can be applied. I'm not sure how a tax or fine can or would be applied with any blockchain. It's also not even clear to me why blockchains are even necessary after skimming the OP.

This is, of course, a problem relevant to many decentralized systems. A user pays me $1 to store their data for 1 month. How do they know I’ll actually do that, and not run off with the money partway through the contract?

Bonding. If there’s a technique which allows for fraud 1 year down the road, then I need to have that much collateral locked in a trust for 1 year. If I behave, I get the collateral back, else I lose it. This discourages me from participating in detectable fraud over that year term.

"Secretly, the mechanism of my capture is temporary"

How is accelerating exothermic mineralization reactions 'temporary', exactly?

Hard to say without more specifics on how exactly carbon captured is proven.

For a concrete example - let's say planting a 50ft tree to maturity constitutes capture. In other words, if I point to a lat and long and show that there wasn't a tree here before, and now there is, I receive the coin.

Well, if you spent energy moving a mature tree from another place, you've not only killed the existing tree, but eventually the tree you've replanted will die too.

That's the sort of scenario I'm referring to.

I fully agree that standard carbon credits are difficult to prove anything about, and even use trees as examples. Are you sure you read my proposal in full?

I only skimmed it (I only read the mineralization section completely) - my question is why is blockchain necessary if an auditor is involved? Isn't blockchain supposed to be zero-trust. Why even use a blockchain at all? I'll have to read your post in more detail later, so apologies if you've already answered these questions.

In any case my concern is more around the second scenario I posed in my first post than the first one.

I agree with your assessment here. The crux this entire theory is built on is the auditing. People will find a way to defraud it, especially if it relies on physical evidence of carbonization. It would have to be highly regulated to deal with your conspiracy scenario. But the fact that it's decentralized makes that incredibly difficult. It's definitely something that has to be considered as a possibility before being practically applied.

> my question is why is blockchain necessary if an auditor is involved? Isn't blockchain supposed to be zero-trust. Why even use a blockchain at all?

A common misconception. Blockchains are zero trust within the state/data space of the blockchain itself. We can refer to these space domains as "on-chain" and "off-chain".

Moving data or state information about the real world, say about the verification of successful carbon capture, to a blockchain is a core part of the oracle problem - which is the problem of migrating off-chain data, to the zero trust on-chain environment.

You use blockchains for the properties of immutability and transparency. In the case of gwern's proposal I can see a market environment where you can claim to capture carbon, provide data, make money (i.e. earn tokens) and then open yourself up to being "attacked" or "slashed". If someone else can make money/tokens by proving you are a liar you create an environment encouraging oracles (data providers) to be honest and accurate.

Final note: gwern pretty much states all of the above in his post, so I would suggest you not skim it.

But the point of the post is to outline a process which is not temporary and is allegedly hard-to-transport.

The immutable state of the blockchain is fine, in fact it’s better because it’s proof of the fraudulent transaction.

It’s possible to write smart contracts in a way that an auditor, or group of auditors who reach consensus, can forcibly remove tokens and freeze accounts, of course this moves the needle towards centralisation more, (and I’m not interested in arguing the merits of that) - Im merely pointing out that immutability is not absolute in the way you are describing and exceptional circumstances and admin overrides can be coded in to EVM based systems at least.

> auditor, or group of auditors who reach consensus

If you are trusting a group of auditors why do you even need blockchain? The method in the OP is interesting, but I don't see the relevance of blockchain at all. Basically it comes down to some magical, incorruptible or comprisable auditor.

That's fine enough, but if you have that, you don't need blockchain to begin with.

You don’t, and I’m not interested in arguing the merits of that. I was pointing out that there are options on a technical level.

I'm not sure what the point of your post is then - it was always possible to do a hard fork if the majority of miners/stakers/users agreed that a certain transactions was bad? That entire problem (consensus) is why blockchain supposedly exists and is purported to solve, no?

I'm not here to argue whether a blockchain is a correct use case or not, that's why I specifically said in my parent comment I'm not interesting in arguing about that, and also said it again in my parent comment. There's always someone here that is looking to pick a fight about "you dont need a blockchain", and I'm not interested in having that discussion (mostly because I agree with it in this case)

But to your point that it's possible to hard fork, well, of course, computers being turing complete you can always go one level deeper into the platform and change the underlying system, but on a practical level forcing all of the miners to upgrade their software and coordinating this is a HUGE effort, and it seems like a very bad architectural decision to force an entire platform upgrade to deal with fraudulent users when safety can be built into the smart contracts themselves.

But I'm not arguing this centralisation is a good idea either, I'm merely pointing out that immutability isn't as final as the original post would make it seem, and there are ways of dealing with the problems they outlined (someone having fraudulently acquired tokens)

Your smart contract proposal doesn't contradict my concerns about immutability. What if the contract is improperly written or does the wrong thing? What would be done then? A smart contract isn't magic. So again I'm not really sure what your point is?

Is it that if everything goes perfectly with smart contracts being written perfectly with no bugs and all contingencies being taken into account and participants of the contract agree to the terms of said smart contracts in the event of fraud that's identified and confirmed it can be reversed? OK, point understood.

This is all interesting. Some questions that came up as reading.

1. "as long as the auditor is trustworthy only to the extent that they will not sign lies about dust not being present"

If they get the staked eth bounty, isn't there a pretty direct incentive for auditors to falsely report dust plots?

2. What happens with disputes? How do you challenge a false report about one of your dust plots? What if both sides are convinced they're correct & being honest -- maybe the dust farmer entered the wrong GPS coords, or the auditor visited the wrong coords, or wrote it down wrong in their notebook. What mechanism is there for adjudicating that kind of conflict?

> Audits rarely needed (hopefully).

This seems highly optimistic: if there’s money involved, cheating is inevitable. Since this inherits Bitcoin’s protections for successful fraudsters, it seems highly unlikely that people wouldn’t just try to dodge audits until the challenge window closes and their transactions can’t be reversed.

Failing an audit by dodging it (how? blocking the roads with trucks? pointing a gun at the auditor's agent?) is a failure.

Same solution in PoS slashing for stakers who don't maintain required latency: too bad, we don't care why, it was your job to do it right, your stake is slashed. (See the NashX exploding equilibrium for another example of this: the buyer doesn't give a s—t whatever excuses the seller might come up with, because it's cheap talk; the seller makes things right, or their stake gets burned. Period.)

Here are just a few things which come to mind – I’m sure there are others:

Flood with volume so there isn’t audit capacity & the time limit expires without a challenge.

Bribe the auditor.

The auditor turns out to be you under an alias.

Setup a mix of legit captured CO2 and something cheaper so when the auditor checks the easiest part to reach it appears valid.

Find something which will trigger the cheapest tests but costs less. Pocket the difference.

Truck the sequestered material from site to site, spending the proceeds long before anyone catches on.

Rely on the fact that since the auditing appears to be completely optional, most people will choose not to pay for it.

Bet on auditors being selected for being as cheap as possible and find the ones who will pass anything plausible.

Flood the system with fake challenges until people demand something like a quorum vote which increases the odds that someone won’t scrutinize your business too closely, or you and your pals try to convince everyone to adopt a more secure fork.

The key thing to remember is that a system which tries to be money is effectively its own bug bounty and it’s much harder to fix problems. Once you have money at stake every angle of the system will be under attack, and the security will come down to the real-world institutions backing it. Blockchains prevent silently rewriting history but that’s only one of the potential things people will try if there’s money at stake.

I'm in the same boat as you. Once there's money involved, I can imagine a lot opportunity for fraud:

-collecting fake "dust" that's the byproduct of another industrial process and minting tokens off it

-bribing or threatening violence against auditors

1. There is no such process, as already noted in OP. 2. Bribing or colluding with auditors only works until buyers or skeptics bring in further auditors, kicking off the forking game, as already noted in OP.

Whay incentive is there for buyers to bring in their own auditors? That costs money too, and if it's anything like the current situation many buyers are just looking to get the carbon off their books. What is their incentive to pay even more after burning the tokens to cover secondary auditing costs? Or for some other third party to insert themselves? And who oversees disputes when the trusted auditor disagrees with the challenge auditor?

I’m disappointed to see Gwern fail to appreciate why social incentivization schemes cannot be decentralized. You have to trust someone (possibly a cartel) to authenticate claims about the state of the world, and that represents a SPOF. The only proof-of-x systems that are any good are systems that can be validated non-interactively and with no trusted third parties.

You can add as many epicycles and “auditors” as you like and this won’t change the core problem.

So, how do I validate my "Bitcoin" blockchain non-interactively, trusting no one? How do I prove I have the blockchain, and I haven't downloaded one that forked some time ago? For that matter, how do I prove that no aliens around Alpha Centauri received transmissions in 2011 of Bitcoin and have been mining a blockchain a million times longer ever since?

You have extremely strong evidence that you have the right chain because artificial network partitions are implausibly expensive to maintain and very cheap to subvert.

The Alpha Centauri example is fair, and that does require a quasi-social process (everyone deciding to ignore the alien chain) to resolve. I say quasi-social because it doesn’t require any coordination or negotiation, but also isn’t fully automatic.

If you haven't interacted with anyone on Earth in 10 years and don't plan to do so in the future, why do you care?

You have a blockchain, that much you can be sure of. If you want the blockchain used on Earth in 2021, you won't need to trust any specific person. If you believe everyone on Earth is lying to you, you are still hopeless and helpless.

Even assuming the proposed mineralization process was effective and consistent with appropriate pre mineralization and post mineralization tests performed...

If you could setup an audit system of the type specified, how does cryptography & blockchain improve upon things? The author seems to acknowledge that question earlier in the article but at the end when it comes saying how this is different, I didn't see a complete answer.

Presumably the goal is to broaden the market. As a smaller player, I can capture carbon today but wouldn’t know how to sell it. I expect there’s some high barrier to entry. By decentralizing and codifying the market portion of this, I know the exact steps to entering the market, and the costs to enter are likely lower.

The reason this works is the third-party auditor. The blockchain doesn't add any value on top of that.

I've read the whole thing twice, and I still don't see any reason why a "blockchain" is an improvement over a centralized system run by an auditor.

> The set of GPS coordinates is invalid if they appear in any previous token.

There probably needs to be something here about overlapping rectangles.

This assumes there aren't other industrial uses for mineralized C02. There are [0] and at least some of them will simply release the C02 again. I'm sure all industrial applications of mineralized C02 would become a lot more popular as easily available quantities became available.

It seems like there needs to be a minimum minting threshold which is much higher than the cost of auditing any point on the planet, so that there is adequate incentive for people to check the coordinates.

> To give 3 examples of incentives/games which can accomplish things software may never can would be:

This portion needs to be rewritten for clarity.

So funny watching people contorting to strap blockchains on to applications that definitely don't benifit from them at all.

Build a proof of CO2 capture

I'm glad you asked how one could build it. As it happens, OP is an entire essay about how one can prove CO2 capture. Perhaps you might enjoy reading it?

The OP essay is about how people might agree the CO2 was captured. I don't see much detail about the actual chemistry of evaluating preexisting carbon in minerals and carbon levels after treatment.

As with all of your texts, I'm sure I will read it more than once

Why not replace the auditor with a Kleros-like system?

But carbon capture is not provable like the energy use from SHA256 hashing. So this is just the 10,000th trashy blockchain scam

Nice effort, but why?

1) There's no need to capture CO2

2) There's no need to record that on a blockchain or use crypto - you could use Github or Gitlab or IPFS with PGP-signed notary statements. Or push commits to all three.

3) Most enterprises are already forced to capture (or pay for outsourced capture, buy CO2 credits and other nonsense), so in order to make CO2 Coin viable in terms of (voluntary) market demand, you'd have to stop the government climate racket first. Good luck getting your friendly government department to give up on the millions of dollars they collect.

4) Considering how expensive global warming racket has become, I can't believe enterprises or individuals can be incentivized to use such a coin. It's much better to just ignore the schema - once the government is out of it (necessary condition for a CO2 Coin), damage from not participating in the racket would be negligible. Nobody wants to pay for it - if they did, we wouldn't have CO2 taxes and excises and no meaningful voluntary contributions.

Trying to dance around the fact that Bitcoin devours energy by slapping CO2 on a new scam. Blockchain pointless here