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by yieldcrv 1480 days ago
here we go again, they use a faulty understanding and a faulty source

> Each Bitcoin transaction consumes around 2,150 kWh as of the time of this writing.

This is wrong because Proof of Work blockchains use the same amount of energy whether any individual makes a transaction or not.

Doesn't anyone else find it ironic that actually understanding how that blockchain works could bolster that particular anti-energy use reaction?

Ah! but the same people don't want to spend any of their own energy understanding how blockchains work because they've already made up their mind that its not worth doing that!

3 comments

I've mentioned this elsewhere, but even assuming that usage doesn't affect mining, why on earth do people think this would be a positive?

----

"My car constantly consumes oil at a prodigious rate even if I only drive it to the grocery store occasionally."

"Even if it's just sitting in your garage? Does... does that make it go faster or further?"

"No, even if my car suddenly starts consuming a lot of additional oil out of the blue, I still can't drive it any faster or further than I could before. The maximum distance I can drive it in a week is a fixed distance regardless of how much gasoline I pump into this bad boy."

"..."

"Anyway, this should probably be the future of transportation."

----

The reasonable conclusion here is not, "when you think about it, driving my car has no environmental impact". The reasonable conclusion is, "holy heck, why would you design a car that way?"

Nobody is saying it is a positive, as I wrote in my post:

> Doesn't anyone else find it ironic that actually understanding how that blockchain works could bolster that particular anti-energy use reaction?

I'm saying make the better, more accurate, argument. I also think if people were able to independently come to those arguments, they would discover things they find interesting about blockchains in the process, as well as where to place that energy

> I'm saying make the better, more accurate, argument.

I do not believe that expending a ton of energy every block regardless of the number of transactions on it means that it's unreasonable or inaccurate to criticize the energy usage in terms of the number of transactions that it on-average supports through that energy expenditure.

I get into this below, but pretty much any system that expends energy to perform a task can be made to act like Bitcoin and expend constant energy regardless of usage by just leaving it running all the time. Doing that doesn't get rid of the "how much energy per-transaction is Bitcoin using" question.

I guess some people have taken issue with the car analogy, so I'll use another: If I leave my shower running 24/7, does that mean that the amount of water I use divided by the number of showers I take is no longer relevant to conversations about my water usage and whether my showering system is water-efficient? No, of course those questions are still relevant, leaving the shower on constantly just makes those numbers really bad for me.

Or yet another analogy, if you're doing math on whether to keep an Amazon Prime subscription, how do you determine if the subscription is worthwhile? Typically, you would add up the number of things you order, and you might say something like, "I'm on average with my current usage paying <subscription cost>/<orders> dollars per-order for same-day delivery using Amazon Prime." And if Amazon jumped in and said, "no, that metric isn't applicable because you'll still pay the same amount with a different number of orders", we would pretty much all recognize that as a bad argument.

Bitcoin has a maximum block size. The fact that in theory people could transact more or less isn't really relevant to the cost/benefit calculation that we're doing right now. Yes, in theory Bitcoin could have max block sizes of 500mb instead of a single megabyte. But it doesn't.

So with the numbers we have now, it is reasonable to say that each Bitcoin transaction cost us 2.5 months worth of household power, even if Bitcoin would have used that power anyway. If the volume of transactions went down, the numbers would be even worse. Bitcoin is currently a system where we can collectively as a society get ~7 transactions per second at the cost of 2.5 months worth of household power for each transaction. I think that phrasing and critique is entirely accurate, and I don't think that the details of the blockchain change anything about that critique or its implications.

Particularly when Bitcoin's energy usage is often compared against much larger financial systems as a way of excusing its excesses, it is entirely appropriate to point that Bitcoin is currently much less efficient than those systems. And breaking things down and looking at the amount of energy per transaction is a reasonable way of determining the network's current efficiency.

Interesting rationale, unfortunately I am not able to see it this way - being more like the Amazon itself who can only see it from the technical way - so lets look at why I can't see it that way and why I find it counterproductive.

Bitcoin is more than transactions, and it is more than onchain transactions, and it is more than its layer 2 transactions which I don't think we can quantify.

It has a much greater use as collateral. It has a much greater use as a reference value for derivatives (sometimes where it is also collateral, sometimes where it is not). As collateral several orders of magnitude more transactions occur - just onchain! And offchain, several orders of magnitude more.

I would say (even if we weren't seemingly in a debate) that none of this justifies its energy use, but only because that is a completely separate phenomenon. Barring any alternative solution for that, I lead to focusing on putting its energy use where it is most applicable and sustainable. Primarily at flare gas mining sites that don't pull from the grid.

I’m not sure that clarifies anything or makes the point you want to, since it would generally be a good thing for a car’s energy consumption to be independent of distance traveled. (“O(1)”)
> it would generally be a good thing for a car’s energy consumption to be independent of distance traveled. (“O(1)”)

No, not unless the energy consumption when taking into account actual average usage is lower than a car where the consumption is tied directly to the same level of usage.

If you really believe that constant rate O(1) is always superior to usage-based consumption, then send me $3000 a month for your electricity bill regardless of how much power you use. Of course, Bitcoin still has an upper limit on how many transactions per-second it can fulfill, so similarly you would still have an upper limit on how much electricity you can use throughout each month.

But, you'd pay $3000 to me regardless of whether you had your fridge running or not, so technically the fridge is now free to run, right?

You’re missing the forest for the trees. Yes, O(1) is not always better, but you’re using an analogy that attempts to demonstrate badness by comparing to a scenario that is generally good. That does not help clarify your criticism!

You’re effectively saying, “that’s bad, because it’s like a good scenario that happens to be bad in this case”. What explanation do you think you’re improving upon?

> by comparing to a scenario that is generally good

It's good if cars use gasoline even when they're not being driven? If people aren't understanding the comparison, then fine, I'm open to better ones, but my point is that it's not improving energy numbers to expend energy even when transactions aren't happening. Even in the world of public transportation, that's an undesirable outcome that we would love to avoid if possible.

I'm not sure what the better comparison would be. Having a fridge lightbulb that stays on even when the door is closed? Running your shower 24/7 to make the number of showers you take independent of the water usage? Take your pick, I'm not married to cars, anything will work.

My point is that anyone can make any system O(1) energy cost by never turning off the thing they're using. You could make your car O(1) energy right now by forcing the engine to run at full speed even in your garage. But in most cases, we recognize that this is bad for energy usage, so it doesn't make sense in the world of cryptocurrency for people to argue that they can invalidate a measure of efficiency as a criticism by purposefully being less efficient.

And I think in those situations, it still does make a lot of sense to compare the total energy expenditure to the actual amount of usage it gets. I don't think that turning on a shower 24/7 means that it no longer makes sense to ask how many showers a household takes, I think that it just makes the water usage to shower ratio really bad. I think similarly, it makes a ton of sense to look at the amount of energy mining is using and compare that to the number of transactions per second that are actually happening on the network.

Reducing it down to "O(1)" is disingenuous. While true, that "1" in the Big-O can actually be pretty large.

If my car burns 30 gallons of gas every week regardless of how much I drive, then that'd be pretty damn bad considering I work from home and drive <15 miles per week on average. The fact that I could then drive a 2,000+ mile road trip and still only burn that 30 gallons doesn't make it good if I never make a road trip like that.

A car that got <max traversable distance in a week> per 30 gallons would be awesome, and the existence of people who don’t drive that much wouldn’t change that fact.

You’re just validating my point that it’s a bad analogy in terms of blurring more than it clarifies.

No, not at all. Let's talk about public transportation.

If you have a public bus that seats at max 20 people, and it's continuously running on a loop, it is entirely appropriate to take the gasoline cost of running the bus for one loop, divide it by the average number of people who ride each loop, and compare that to the costs of normal transportation.

If the bus uses way more gasoline per loop than is justified by transporting 10-20 people each loop, then riding the bus is bad for the environment. It would be wild to look at that situation and say, "well, the bus is going to spend that power regardless, so actually riding it is environmentally free and the criticism doesn't make sense."

The bus exists because of the passengers, and how much work it's doing per loop and the number of passengers it's serving should factor into an analysis of whether it's worth keeping it around.

Similarly, Bitcoin's POW system exists to provide transactions, and it is entirely reasonable to take the average number of transactions it processes per block and ask whether it's good that Bitcoin spends so much energy to process so few transactions.

It's especially valid to question whether it's good that Bitcoin's energy usage can increase without increasing the number of transactions it handles. At least with a public bus, the amount of gasoline it uses doesn't start dramatically rising just because the bus became more popular, independently of how often it makes a loop or what its seat capacity is.

The existence of such a car might be nice, but if everyone owned one of them, it'd be an utter disaster.
> Proof of Work blockchains use the same amount of energy whether any individual makes a transaction or not.

Not entirely; that depends on the blockchain in question and on how much block subsidy is left. For bitcoin at this time (as well as for blockchains with a tail emission at any time), it's mostly correct since tx fees are a small part of the block reward. But in a few decades the bitcoin tx fees will dominate the every halving block subsidy.

The article is really about the environmental cost of the network. Breaking it down to transactions is just a basic tool to promote understanding and quite a common one (like in cost of ownership ratios.) Mind that the whole purpose of the network is still to enable and maintain these transactions. The article eventually transitions from there to the total cost of the network in TWh and the number of those participating in this network by individual transactions.
Its next section does slightly better, after doubling and tripling down on the household consumption framework.

The source of energy is way more important, bitcoin's source of energy is pretty good compared to any industry, and it can be better. Individual vigilance should be placed on ensuring that the overall source of energy for bitcoin gets better. because some of those major sources are reducing pollution and emissions. more mining can happen at more of those places. while other energy sources can be avoided.

Except that energy usage is mostly zero-sum: if Bitcoin is using all renewable energy sources [0], then all other uses of energy must use dirtier sources if those sources are already heavily utilized by bitcoin. Homes have to use more coal if Bitcoin is using all the wind/hydro. The pool of available energy resources is currently quite finite and while "the grid" abstracts away most of the sources from your view as an electricity user, it doesn't eliminate the fact that there are some very big zero-sum tradeoffs between the sources and "the grid" will adjust to increased demand with increased supply of increasingly dirty sources to meet that demand.

[0] Which is a presumption that is extremely arguable given how much we've seen shutdowns/restarts of coal-powered plants in for instance China and Kazakhstan impact the Bitcoin mining pools over time.

> Except that energy usage is mostly zero-sum

So great that its not totally zero-sum. Now that we both acknowledge that, and a large portion of bitcoin mining is using energy sources that are not taking away from other energy uses, and a larger portion of bitcoin mining can use more of this kind of energy. Because, well we've come full circle, Bitcoin doesn't use that much energy. There is way more untapped energy, thats been there for decades just being wasted and spewed away, because nobody else could figure out a use for it.. except the bitcoin miners.

You have a very different understanding of the word "mostly" than I do. You are also presuming that by the parts not covered by "mostly" in my hedge that I mean "positive sum", but I very much was considering and including cases that are truly "negative sum" games where more consumption is actively worse for all players involved. (For physical example: blackouts and brownouts.)

You are also assuming that Bitcoin is a good use of energy, which is also not something that I would agree with. Bitcoin mining is a massively distributed partial preimage attack on a cryptographic hash function of some importance to internet/world security and I have a very hard time seeing that as a good (both as in good ethics and as in good utility) use of energy.

Yes, I'm familiar with the flowchart and how the goal posts always move to "but I don't like that energy use anyway, so it doesn't matter how wrong I was earlier, surely something else must be able to use that energy". correct me if I'm wrong because its not intended to be a strawman.

But, bitcoin mining at flare gas sites disconnected from the grid is a significant source of the amount of energy being used bitcoin mining, and this use reduces pollution and emission over 60%, and it takes away from nothing else. And if there was any vigilance towards proof of work it should be to ensure more of this happens, and less of other sources. because obviously the flaring isn't going to stop, and the proof of work isn't going to stop, so lets focus on the parts you can influence.