Bitcoin Could Cost Us Our Clean-Energy Future

By Eric Holthaus, a meteorologist and contributing writer for Grist, covering climate science, policy, and solutions. He has previously written for the Wall Street Journal, Slate, and a variety of other publications. Originally published at Grist

If you’re like me, you’ve probably been ignoring the bitcoin phenomenon for years — because it seemed too complex, far-fetched, or maybe even too libertarian. But if you have any interest in a future where the world moves beyond fossil fuels, you and I should both start paying attention now.

Last week, the value of a single bitcoin broke the $10,000 barrier for the first time. Over the weekend, the price nearly hit $12,000. At the beginning of this year, it was less than $1,000.

If you had bought $100 in bitcoin back in 2011, your investment would be worthnearly $4 million today. All over the internet there are stories of people who treated their friends to lunch a few years ago and, as a novelty, paid with bitcoin. Those same people are now realizing that if they’d just paid in cash and held onto their digital currency, they’d now have enough money to buy a house.

That sort of precipitous rise is stunning, of course, but bitcoin wasn’t intended to be an investment instrument. Its creators envisioned it as a replacement for money itself — a decentralized, secure, anonymous method for transferring value between people.

But what they might not have accounted for is how much of an energy suck the computer network behind bitcoin could one day become. Simply put, bitcoin is slowing the effort to achieve a rapid transition away from fossil fuels. What’s more, this is just the beginning. Given its rapidly growing climate footprint, bitcoin is a malignant development, and it’s getting worse.

Cryptocurrencies like bitcoin provide a unique service: Financial transactions that don’t require governments to issue currency or banks to process payments. Writingin the Atlantic, Derek Thompson calls bitcoin an “ingenious and potentially transformative technology” that the entire economy could be built on — the currency equivalent of the internet. Some are even speculating that bitcoin could someday make the U.S. dollar obsolete.

But the rise of bitcoin is also happening at a specific moment in history: Humanity is decades behind schedule on counteracting climate change, and every action in this era should be evaluated on its net impact on the climate. Increasingly, bitcoin is failing the test.

Digital financial transactions come with a real-world price: The tremendous growth of cryptocurrencies has created an exponential demand for computing power. As bitcoin grows, the math problems computers must solve to make more bitcoin (a process called “mining”) get more and more difficult — a wrinkle designed to control the currency’s supply.

Today, each bitcoin transaction requires the same amount of energy used to powernine homes in the U.S. for one day. And miners are constantly installing more and faster computers. Already, the aggregate computing power of the bitcoin network isnearly 100,000 times larger than the world’s 500 fastest supercomputers combined.

The total energy use of this web of hardware is huge — an estimated 31 terawatt-hours per year. More than 150 individual countries in the world consume less energy annually. And that power-hungry network is currently increasing its energy use every day by about 450 gigawatt-hours, roughly the same amount of electricity the entire country of Haiti uses in a year.

That sort of electricity use is pulling energy from grids all over the world, where it could be charging electric vehicles and powering homes, to bitcoin-mining farms. In Venezuela, where rampant hyperinflation and subsidized electricity has led to a boom in bitcoin mining, rogue operations are now occasionally causing blackoutsacross the country. The world’s largest bitcoin mines are in China, where they siphon energy from huge hydroelectric dams, some of the cheapest sources of carbon-free energy in the world. One enterprising Tesla owner even attempted to rig up a mining operation in his car, to make use of free electricity at a public charging station.

In just a few months from now, at bitcoin’s current growth rate, the electricity demanded by the cryptocurrency network will start to outstrip what’s available, requiring new energy-generating plants. And with the climate conscious racing to replace fossil fuel-base plants with renewable energy sources, new stress on the grid means more facilities using dirty technologies. By July 2019, the bitcoin network will require more electricity than the entire United States currently uses. By February 2020, it will use as much electricity as the entire world does today.

This is an unsustainable trajectory. It simply can’t continue.

There are already several efforts underway to reform how the bitcoin network processes transactions, with the hope that it’ll one day require less electricity to make new coins. But as with other technological advances like irrigation in agriculture and outdoor LED lighting, more efficient systems for mining bitcoin could have the effect of attracting thousands of new miners.

It’s certain that the increasing energy burden of bitcoin transactions will divert progress from electrifying the world and reducing global carbon emissions. In fact, I’d guess it probably already has. The only question at this point is: by how much?

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  1. skippy

    Bitcoin – whilst sucking energy in an attempt to reconcile antiquarian ideological theological beliefs, about how one earns a bob, and how that is spread across assets wrt how one has access to goods and services is a proverbial theoclassical post modern saw movie.

    Long ago on this blog I referenced an old SciFi novel, first human contact with an alien species, tho they went extinct before humans arrived. Long story short, biological events doomed the species, upon the arrival of humans much speculation was afforded the litter of objects strewn about because of its frequency and seemingly haste in the final days.

    Humans enviably contracted the same biological infection, last man standing concocted a suit that matched the alien physiology and deduced that the objects was their form of money……

  2. Expat

    This is insane. But then again, so is Bitcoin at $14,000. or $15,000 or wherever it is as I type this.
    The conversation about Bitcoin has gone from “it is all about freedom from Big Brother and having a stable, reliable currency” to “woohooo! Bitcoin 100k!!!! ‘currency!? Who cares? Woohooo!”

    I always thought Bitcoin was stupid but I also thought it was green since it got rid of paper or metal. Whoops. Guess not.

    1. Jane

      What’s even more insane is the amount of wasted energy. Only the miner who is the first to prove a block of transactions gets paid, so if a 100 miners each spend 10 minutes working on a block, 99 of them get nothing for their efforts and the energy used for those 990 minutes might as well have just been blasted out to the ether.

      The same is true for proving individual transactions, the person who proves it earns a small fee so while the number of bitcoins generated, in total, is limited to 21 million there is no limit to the number of transactions possible increasing the energy usage (and waste) even more.

      3Blue1Brown has a very good explanation of how cryptocurrencies are generated.

      1. miles

        None of that energy is wasted — it directly contributes to the security (against double spends) of the network. It’s called “proof of work” for a reason. There would be no real security without competition.

        The number of transactions is limited by the available space in a block (now a ‘weight’ limit, but suffice to say it’s a hard limit) and the number of blocks generated (regulated to one block every 10 minutes on average). Even if TX throughput grows, miners’ income is still limited by the amount that people are prepared to pay in fees. That is not a recipe for a continuous, exponential rise in energy consumption. Energy consumption will almost certainly plateau.

          1. jrs

            and what does it matter if energy consumption plateaus if it’s still energy that wouldn’t be used otherwise (of course the last part is debatable given Jevon’s paradox etc. but if whole new energy sources are built for this nonsense then yes …)

        1. TK421

          That’s insane. That’s even worse than if the energy *was* wasted, because waste implies a place to cut back excess, but if these absurd levels of energy are required for Bitcoin to work then it’s time to nuke this thing from orbit.

    2. nonsense factory

      I thought about this a bit and then look up the energy consumed by streaming video:

      The energy cost of streaming video
      Lawrence Berkeley Lab
      Monday, June 2, 2014

      You might think streaming video might be a greener way to enjoy a movie than driving to the video store for a rental. You’d be right, but don’t pat yourself on the back yet. Researchers at Lawrence Berkeley National Laboratory (Berkeley Lab) have analyzed the energy usage of home movie viewing. They found that transmitting the bytes across the Internet accounts for the bulk of energy usage and emissions when streaming videos.

      In 2011, Americans streamed 3.2 billion hours of video (that’s a lot of “Game of Thrones” and “Breaking Bad,” folks). All that streaming consumed 25 petajoules of energy [about 7 tera-watt-hours] — enough to power about 175,000 U.S. households for a year — and emitted 1.3 billion kilograms of carbon dioxide.

      After doing some online conversion, and assuming the 31 tera-watt hours for bitcoin transactions is accurate, that means more than four times as much energy is used for bitcoin as for streaming video. That’s pretty astonishing. Of course, video streaming rates might have gone up a lot since 2011.

      1. blennylips

        Perspective, folks. (I choose units such that =c=1;)

        SAN FRANCISCO, May 7, 2015 /PRNewswire-USNewswire/ — Approximately $19 billion worth of electricity, equal to the output of 50 large power plants, is devoured annually by U.S. household electronics, appliances, and other equipment when consumers are not actively using them, according to a groundbreaking study released today by the Natural Resources Defense Council.

        How many Households in a power plant?

        …They are, however, dependent upon vast complex infrastructures that are increasingly strained. One such system is electricity supply; demand for which is outstripping the deployment of nuclear and renewable energy generation. The relatively straightforward process of swapping renewables and nuclear for fossil fuels has been thwarted by the demand that these must simultaneously power the electrification of the economy and provide the gazillowatts of new energy required to power an entirely new “internet of things” – of which the voracious energy consumption of cryptocurrencies is just a tiny part.

        Ƀ is a danger to TPTB, gotta vilify…

  3. Samuel Conner

    Another technology widely spread before its implications were understood sufficiently well to be able to determine whether it was indeed a good thing. We keep doing this.

    1. JTMcPhee

      SOME of us keep doing “this,” releasing various forms of pathogens, like bitcoin and AI and autonomous weapons and CRSP-R ad nukes, into the living planet ALL of us depend on for sustenance. And because there are enough “some of us’s” who have a certain kind of grasping insouciance, or maybe unrecognized or even patent death wish, one might expect that ALL of us will die off from one or a combination of several of the plagues that the some-of-uses get some kind of seeming personal gain from.

      Stupid family blogging species.

      1. JTMcPhee

        And seagoing pirates, and the various “navies” of the world, and now those oil platforms and ships built to exploit the “wealth lying free on the sea floor” and “gather” all the fish and other lootable biota, all instruments of looting and extraction.

        He, we’re only human…

        1. Petter

          Virilio’s point is that every technology brings with it it’s own accident, it’s built in.

          From an interview in Vice from 2010:

          Virilio is into revelations. He’s like some kind of prophet of the apocalypse. There are no moral judgments in his work, even though he is a devout Catholic. He deals more in the observation and analysis of banalities, or “evidences,” as he calls them. His best-known statement is “The invention of the ship was also the invention of the shipwreck.” It’s probably the most concise and eloquent explanation of causality we’ve ever read, and it can be applied to almost anything. Virilio expands this into what might be his main message, which is, to paraphrase, that every technological invention bears its specific defect in its DNA and that the cult of speed and acceleration that technology has engendered will be the death of us all.

    2. patrick

      “Another technology widely spread before its implications were understood sufficiently well…” Exactly Sam! but, but but money!! – asbestos and lead come to mind. On a related note- the demonization of cholesterol has brought us statin drugs which are one of the most lucrative, unhealthy and unnecessary pharmaceuticals in history. We are all sheep, at least some of the time.

      1. Mercy Vetsel

        “Another technology widely spread before its implications were understood sufficiently well…”

        Yes, like electricity, the light bulb, indoor plumbing, antibiotics, the steam engine, the semi-conductor, the internet — basically every technology we have.

  4. fajensen

    Bitcoin is just another indicator that “Markets” have lost their purpose and gone totally psychotic, losing even their last, tenuous, connection to reality that perhaps once existed.

    It will end and it will end quite suddenly, being all driven by bots and hardwired algos in FPGA’s.

    Once Bitcoin crashes, the power required in mining it will go away. Gamers might buy the salvageable hardware cheap on the bankruptcy auctions, then the power consumption comes back to some degree.

    It doesn’t have to crash, a good solar flare will do away with Bitcoin too.

    1. Jim Haygood

      From another perspective, Bitcoin mania confirms that central banks have lost their purpose and gone totally psychotic.

      QE provided both the superfluous liquidity and the reason underlying the instiable demand for cryptocurrencies: namely, that rag-paper-and-fiat currencies are in the utterly irresponsible hands of central bankers who have ginned up a global bubble with their batsh*t crazy experiment.

      To paraphrase one of my favorite T-shirts: Economist, Rope, Tree: some assembly required.

      1. Grumpy Engineer

        Yes. I had the exact same thought. The tremendous demand we see for Bitcoin would have never appeared if our various central banks (i.e., the Federal Reserve, ECB, BoJ, etc.) hadn’t utterly flooded financial markets with excess money over the past decade.

        Speculating in bubbles is actually profitable when the central banks are perpetually increasing the volume of money with which investors can speculate. And those of us who are too poor to hop on the speculative bandwagon get left behind. Why yes, let’s mash on the Gini index accelerator pedal even harder!!

      2. jrs

        I don’t know that is even the real demand, the real demand might be for transactions that would otherwise be illegal (not saying they all should be but they are), but also at this point the ultimate demand is probably in LARGE part PURE speculation, nothing else.

      3. JTFaraday

        That supposed skepticism of central bank money is driving the creation of this particular bubble to the cheers of its true believers, and they seem not at all aware of that, is very ironic.

      1. Andrew Dodds

        That’s what I was thinking at $10k..

        Also, ‘wish I’d bought a few when I first heard of them..’

  5. The Rev Kev

    Dmitry Orlov has an interesting take on Cryypto-Currencies over on Russia Insider at and in it he mentions CryptoKitties which I have read are sucking up vast amounts of energy to the point of interfering with actual bit-mining. Those CryptoKitties seemed somehow familiar until I remembered where I had seen them in the past – the Tamagotchis ( from the 1990s. Maybe we should have just gone with pet rocks from the 1970s instead. At least they were energy neutral.
    Until we can perfect fusion energy or matter-antimatter engines or Zero Point Modules maybe, just maybe it might be wiser to regulate the hell out of Cryypto-Currencies by calling it a stock with all the laws that would apply to such transactions. When it gets to the point that Wall Street is setting up a futures market on them then you now that the time to bail on them is close. I was going to say how those currencies are attached to nothing of value but that is true of all fiat currencies, especially after Nixon cut the link to gold decades ago. The colossal explosion of credit since then I personally lay at his door. These Cryypto-Currencies I consider to be another variant.

    1. Keenan

      When it gets to the point that Wall Street is setting up a futures market on them then you know that the time to bail on them is close.

      Looks like the time is now:

      “Both CBOE Global Markets and CME Group are set to launch the new futures contracts on Dec. 10 and Dec. 17, respectively. With the notable shift in the industry, bitcoin may remain well bid at least until Sunday’s listing of BTC futures on the CBOE.”

  6. Ferd Nern

    Tulips, anyone?
    Cryptocurrencies almost immediately diverged from any representation of transactional worth and have gone straight to speculation. That exponential curve isn’t a good indication of long term stability. Like Star Trek collector plates and limited edition baseball cards, their value is virtual and collapses when too many speculators try to cash in.

    1. TK421

      Yeah really. People are buying them in hopes that other people will buy them. What happens when everyone who wants some has some?

      1. Mel

        Well, that’s the trick! Nobody wants them. The only reason people get them is they can’t get rid of them if they don’t have any.

    2. Vatch

      The good thing about tulip bulbs is that one doesn’t need to wast huge amounts of energy generating them. Some soil, sunlight, and a little water is all that’s needed. No greenhouse gas emissions.

  7. Louis Fyne

    yes, bitcoin electricity use should be looked at (but the majority of the mining is outside the US). but there are a lot of low-hanging energy efficiency fruit…..that could’ve been better/more forcefully addressed in the post-2008 stimulus package.

    new windows/doors, modern water heaters/furances, insulation, refrigerators, etc. i’m too lazy to do the math. but it should be easy to figure out what would happen if 85% of homes/business in America were up to modern efficiency standards.

    And PS, throw in getting rid of electricty vampires around the house, like cable boxes.

  8. Wukchumni

    Devil’s advocate dept:

    What if all that glitters put in a performance like bitcoin, over the past 5 years, going from $20 to $15k?

    The spot price would be a sparkling million dollars per ounce…

    1. moss

      Mining, and particularly gold mining with its grades in the 1-2g per ton, requires enormous amounts of energy to mine, grind and extract. One cannot but wonder whether the end result of this polluting activity is any more useful or beneficial to mankind than bitcoin

  9. Tobin Paz

    Naked Capitalism is one of my favorite sites. I rarely post due to my poor knowledge of economics and finance… I’m here to try to learn. These last two articles about bitcoin’s energy usage are puzzling for a variety of reasons. First, the claims are so outlandish that they almost defy belief.

    Did Anyone Do Even a Minimal Check on the Sensationalist Bitcoin Electrical Consumption Story?

    And so, um, bitcoin mining is a threat to the planet because it consumes less than 1% of all the electricity squandered by appliances and devices on stand-by? If we want to stop wasting so much energy, perhaps we should start by mandating near-zero stand-by power consumption for the hundreds of millions of devices which are not in use that are nonetheless sucking up electricity every second of every day.

    Second, why is the energy consumption of the current system not put into this context? Workers don’t walk to their financial offices, which don’t heat themselves, or power their appliances, lighting, and computers with no environmental impact. The bitcoin energy usage is not only a tiny fraction in comparison, but has the capability to take down the banking system as we know it. No more Wells Fargo’s, Jamie Dimons, etc. Creating money out of thin air has allowed the United States to go on a crimes against humanity tour of Afghanistan, Iraq, Libya, Yemen, Syria, etc.

    Third, and this is where I wish I knew a tenth as much as Michael Hudson, the current form of money creation is predicated on growth. You can’t have infinite growth on a finite planet. The present monetary policy is what allows the oil industry to borrow and still be in the red. Not acknowledging the relationship between energy and money has been a factor in bringing us to the this point.

    The reality is that humanity has one foot in the grave. We are still talking about reducing green house emissions at a time when we need to extract carbon dioxide from the atmosphere. The irony is that we have to continue full steam ahead burning fossil fuels because the alternative would be a collapse of civilization as we know it… no energy, no growth, no food, no medicine, no many things that keeps us civilized.

    Unfortunately renewables are not going to save us. Not only are there not enough resources on the planet to produce the required infrastructure, they are not even close to replacing the current, let alone future, energy requirements of humanity as we know it. And this is where the concept of peak oil rears it’s ugly head. I don’t understand why this topic is so taboo.

    Personally, my outlook of our current trajectory is rather grim. If we even want the opportunity to throw a Hail Mary we need to start having an honest conversation about the extremely dangerous condition of the Arctic, the destruction of our habitat in the name of capitalism, and the undeniable reality that at some point in the near future we won’t have enough energy to extract or process the remaining fossil fuels in the ground. Instead we will continue to demonize Trump and the dirty Russians that against any basis in reality put him in office. What a disaster.

    1. Outis Philalithopoulos

      When you say that “the claims are so outlandish that they almost defy belief,” you are not reporting accurately the conclusions of Charles Hugh Smith in the article you link to.

      Smith does not dispute the claims per se, aside from the exact figure used for energy consumption per transaction. The article he criticizes gave 215 kWh/transaction, and Smith notes that estimates vary and so cooks up an alternate “conservative” number of 135 kWh/transaction. The recent study by Digiconomist however reviewed prior studies and came up with a number of 250 kWh/transaction, arguing that “in the past, energy consumption estimates [… have used] an approach [that] will certainly lead to underestimating the network’s energy consumption, because it disregards relevant factors like machine-reliability, climate and cooling costs.” In other words, after careful work, Digiconomist comes up with a number higher than the one Smith assumed was too high.

      The central point Smith is making is that energy consumption figures can be contextualized in various ways. The article he refers to compared Bitcoin energy consumption to that of Nigeria; Smith compares it instead (citing a NYT article) to the total amount of energy used in the world by electrical devices on standby.

      This isn’t a situation where one can say that a given sort of comparison is simply wrong – in fact, the NYT article cited favorably by Smith states that “[The amount of energy I use with my coffee-maker in a year, with about 10 minutes of usage per day] comes out to about 50 kilowatt-hours every year, or a little more than what someone from Niger uses in a year.”

      To be sure, one could reason that since Bitcoin doesn’t consume as much as devices on standby, then its energy consumption isn’t a problem. That isn’t the stance of Bitcoin defenders on this site, who in response to Enrico Verga’s recent article argued not that the energy trajectory was a non-issue, but that the Bitcoin community realizes it is a problem and is on track to deal with it eventually.

      One could just as well respond to the comparison as follows: “Devices on standby waste a lot of electricity and this is a problem. Bitcoin eats up a lot of energy and this is also a problem. Currently the former is a bigger problem in magnitude, but the latter problem is growing rapidly. Therefore there are reasons to be concerned about both.”

  10. False Solace

    Imagine if they put the same effort, energy, and CPU cycles into something actually beneficial like distributed modeling of protein folding. Instead we witness yet another example of idiot humans chasing after personal claims on resources, and dooming their entire species in the process. I hope the species that replaces ours in the food chain (however many millions of years it takes to reestablish a food chain) has more wisdom and kindness.

  11. miles

    I’d like to see what % of Bitcoin mining takes advantage of renewable or otherwise unusable energy (solar, hydro, geothermal or excess). I suspect it’s high (because miners will find the lowest cost electricity). It might be so high that it actually encourages new renewable energy initiatives (enriching the original plant owners and prompting the development of new sites).

    One of the reasons mining concentrated in China was because of the huge (and mostly unused) hydro facilities (meant for cities that didn’t populate, and with no infrastructure for moving the excess energy around the country).

  12. Grumpy Engineer

    Hmmm… Mining for bitcoins may be an activity of diminishing returns. After all, 16.7 million out of a possible 21 million coins have already been mined: That’s nearly 80% of them.

    The guys who are ramping up these giant energy-slurping mining farms will eventually find that they can’t successfully mine anything. Because there aren’t any coins left to be mined.

    1. milesc

      Miners earn fees paid on each transaction. Over time, miners will become more dependent on fees and less dependent on newly minted bitcoin.

  13. JTFaraday

    “a decentralized, secure, anonymous method for transferring value between people.”

    Maybe there’s some use for this blockchain technology underlying bitcoin, but bitcoin itself seems an even dumber gimmick than the Platinum coin, (which at least didn’t have to be plugged in).

    How do we invest in blockchain technology without the dumb coin gimmick? When you have to attach the plug to an appliance with some productive real world use, most of those farms are going on off, because no one is going to be paying them.

    There’s probably an analogy to our whole system of pointless financial mis-engineering in there somewhere.

    1. milesc

      When you sit down and consider what a blockchain actually does, you quickly realise that “blockchain not bitcoin” makes zero sense. There is no other reason to purposefully bundle transactions into blocks and periodically extend your chain of blocks. The time between blocks exists to accommodate proof of work. It’s gloriously slow and inefficient (when compared to traditional shared database options) by design and necessity!

  14. Tomonthebeach

    Note to Grist. trying to squash Ponzicoin by appealing to Greeners is non sequitur. Most Greeners do not have two bitcoins to rub together (figuratively speaking), and thus – the guesstimated drain on the grid – even assuming it is correct (sorry I lack the app to compute it) is unlikley to kill digimoney.

  15. Dugh

    Interesting recent paper on quantum computers and cryptocurrency vulnerability:

    Quantum Attacks On Bitcoin

    Vulnerability appears to be in “signature scheme” and not “proof-of-work”.

    “Signatures in bitcoin are made using the Elliptic Curve Digital Signature Algorithm based on the secp256k1 curve. The security of this system is based on the hardness of the Elliptic Curve Discrete Log Problem (ECDLP). While this problem is still believed to be hard classically, an efficient quantum algorithm to solve this problem was given by Shor [Sho99]. This algorithm means that a sufficiently large universal quantum computer can efficiently compute the private key associated with a given public key rendering this scheme completely insecure.”

    1. ChrisPacific

      …given the existence of a sufficiently large universal quantum computer, which is not currently the case. But might be in future.

    2. milesc

      The quantum threat is well understood — it was raised by Bitcoin developers years ago. Bitcoin is reasonably well positioned and can be upgraded in good time (Bitcoin is not a finished product, and likely never will be — it is constantly evolving!).

      > a sufficiently large universal quantum computer can efficiently compute the private key associated with a given public key

      ^ This is a bit misleading. Note that Bitcoin public keys are hidden (hashed), so this problem (computing the private key associated with a given public key) is more relevant in cases of address re-use, which can help unmask public keys (hence address re-use is strongly discouraged and no longer default wallet behaviour). If quantum computers crack SHA256, Bitcoin will be in much the same position as the rest of our financial and telecoms infrastructure (i.e. compromised and in need of an immediate upgrade). People expect quantum secure cryptographic algorithms to be put in place long before that happens, of course.

  16. joe defiant

    Until the “civilized” world is ready to give up on car culture, plasticization, consumerism, and a growth based economy pushing the blame around on things you personally dislike is nothing more than virtue signaling.

  17. Michael

    This would be a perfect opportunity to push for a tax on energy. The number of people using crypto-currencies is such a small percentage the population, it might be passable.

    Think of the consequences….

    1. jrs

      yes a properly implemented carbon tax would probably prevent such stupidities as a currency based on energy burn.

      1. milesc

        It’s not just a currency (or commodity or whatever). It’s a payment and settlement network too. It’s actually quite efficient (vs the infrastructure required to support your bank account and debit card, for example).

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