The Cambridge Bitcoin Electricity Consumption Index gives a much higher estimate (78 TWh vs. 117 TWh), which makes it about the same as the annual electricity usage of United Arab Emirates (pop. 9.9 million).

https://www.cbeci.org/

That doesn’t change anything in energy usage, and shows how you fundamentally don’t understand how it works.
Reduced mining rewards will indeed reduce the amount of energy spend. Just check the price surges/declines of the past.
The energy usage of Bitcoin is directly related to the revenue available to BTC miners. As mining rewards decline, so does energy expenditure to mine BTC.
BTC miners make significant money from transaction fees which largely offsets future drops. Unfortunately, if rewards drop enough 51% attacks become possible so Bitcoin requires massive energy expenditure to remain viable.

The basic equation the rewards from mining using X hardware over it’s useful lifetime vs the rewards from using that hardware for a 51% attack.

>BTC miners make significant money from transaction fees which largely offsets these drops

Today’s block subsidy is currently 6.25 BTC, and the amount with fees is around 7.2 BTC. That’s nowhere close to the pre-halvening about of 12.5 BTC.

You’re looking backwards not forwards. Assuming transaction fees of 1BTC / block, the next drop isn’t to 3.125 BTC it’s ~4.125 BTC and the drop after that is to 2.5625 not 1.5625. In roughly 3 drops subsidies will be less than block fees.

Not that 1BTC per transaction is anything close to a constant, maximum rewards over the last 3 years where more than 100x minimum rewards, but it does seem independent of block rewards.

The vast majority of BTC miner revenue – around 90% – comes from block rewards:

https://www.blockchain.com/charts/miners-revenue

With every halving, assuming price remains constant, BTC miner revenue, and with it, energy expenditure, declines, until it’s 10% of current energy expenditure.

You’re right that this could pose problems for Bitcoin’s security, but that’s unrelated to the fact that Bitcoin miners’ energy expenditure as a share of BTC price will decline.

It’s nowhere near consistent enough to say 10% going forward, as block rewards per day have been anything from 1400 to 10 BTC per day over the last 3 years.
I don’t care about the energy issue. See actual sources of most of bitcoins energy. (Nat gas, thermal, etc that would be otherwise wasted.)
It seems really weird to compare the energy consumption to that of a country.

“The total energy usage for the production of cars/yachts/fitness machines/musical instruments/toilets equals that of country X”

What does it even mean? How do you interpret it?

It seems more sensible to compare to total worldwide energy consumption of which Bitcoin takes roughly 0.05%

Countries have millions of people in them, which are doing many things with that energy. It illustrates the waste.

Visa is an alternative technology providing a service that bitcoin is intended to replace (preemptive statement: I am simplifying and very familiar with the crypto true believers various conceptions of what crypto currency “really is”, don’t waste your time not picking this please), so it is a valid comparison to illustrate the inefficiency

> Countries have millions of people in them, which are doing many things with that energy. It illustrates the waste.

But Bitcoin is something that people are doing with energy in countries. It is 1/2000th of the average person’s footprint.

Is doesn’t seem reasonable to call, say, people flying around in airplanes doing something with energy while calling Bitcoin “waste”.

You would have to show that bitcoin transactions are globally uniformly distributed for that claim to hold well.

The rest of you argument hinges on the idea that the value created by bitcoin on-chain transactions is equivalent to that of airplane usage (the fact that our current air plane usage is wasteful aside), an argument I won’t get into without evidence-of-good-faith

I am simply pointing out that the usage of Bitcoin or something else is better assessed as comparison to global consumption. Trying to map energy usage per product/category to energy usage per country is not insightful and misleading, as it suggests the product/category is not part of the country’s energy consumption.

I am not at all arguing that Bitcoin is useful, or that its energy consumption isn’t excessive.

> (preemptive statement: I am simplifying … don’t waste your time not picking this please)

You admit that it’s a strawman to say Bitcoin is meant to replace Visa.. but then why argue that?

Because one of the constantly shifting goal posts that the crypto community used a lot in the past is “payment method without third parties”. So it is relevant to compare to Visa, to establish that Bitcoin utterly sucks in that regard, without 2nd, 3rd etc. layer solutions.

There is a lot of accusations of “straw manning” when people calmly point out that except as a gamble and to enable relatively small amount of criminal transactions, Bitcoin has as of now failed to do in anything of the many things its true believers want it to achieve.

I have actually been following the crypto space since the cypherpunk days (by reading archives early on because I’m too young to have been around since the true start) and without regret (okay, a little bit of regret 🙂 missed out on large gains by selling all my crypto early on. One of the more interesting projects https://en.wikipedia.org/wiki/GNU_Taler doesn’t get enough hype because it doesn’t make claims that make you feel like a badass outlaw, sticking it to the man and potentially avoiding taxes. I still hope it takes off because it would be an actual digital cash, privacy preserving while still allowing for societal important things like taxes to work.

> Bitcoin has as of now failed to do in anything of the many things its true believers want it to achieve.

It’s already successful. First of all: simply by enabling new methods of civil disobedience and eliminating future opportunities for government overreach it is already working to strengthen our democracy. Second, people are actually using it today to escape oppressive currency controls in certain places like Argentina. And there is real potential for Bitcoin to act as an inflation hedge that is much more convenient than gold (we have yet to see the long-term price behaviour).

Can not withstand, sorry: Bitcoin is a store of value nowadays. If you want to compare it in an environmental-impact way then compare it e.g. against gold mining.
Bitcoin smoothly moves between store of value and next level of banking whenever fees rise to high to transact or a new tech which is totally gonna make it scale and be affordable for micropayments respectively.

As a store of value it is utterly unusable due to volatility. Like gold, another perennial favorite of a similar crowd.

Depends on the crowd size and philosophy. The only true store of value is a diverse portfolio, anything below that you need to use your own priors and data to decide what kind of risk you take.
bitcoin was just an idea a few years/a decade ago and is now here.

Its existing directly consumes as much energy as a whole fucking country.

I find that a very visible and easy comparision.

If i would invent something and it would consume that much energy just for transactions, i would consider this a gigantic issue.

Considering you’re talking worldwide energy consumption, 0.05% is a lot of energy. Just because the number is small doesn’t mean it’s not large by comparison.
True, but similarly just because the number is big in an absolute sense also doesn’t mean it is actually a worthwhile target for reducing emissions. There are plenty of lower-hanging fruit.
It’s 0.05% of energy that could be used elsewhere to reduce emissions (since a lot of miners sit on renewable energy). It’s a worthwhile target because it#s easy to fix: don’t waste energy like that.

edit: additionally a lot of small crap is still a pile or crap at the end of the day, the small little energy wasters (comparatively) still make up a combined total that is wortwhile to take on.

That isn’t an easy fix though, unless you can find some other way to replace the unique advantages that Bitcoin is providing to users.

This is like saying “killing combustion engines is an easy fix: Just don’t drive!”

The fix is to use alternative consensus mechanisms like PoS. It’s not “killing combustion engines is an easy fix: Just don’t drive” it’s “killing combustion engines is an easy fix: Use more efficient types of engines such as electric or sterling motors”.
I can agree with you that PoS is the most promising fix, but even still I don’t think it’s an easy fix just because the technology exists.

For example electric engines are an easy fix technically, but there are still lots of political and practical barriers that need to be solved before they can achieve widespread adoption.

It will take time for the market to build the same level of trust in PoS systems that they have in PoW systems.

Because you’re comparing the energy consumption of this one thing to the total energy consumption of $x million households along with all the country’s local industry to say that Bitcoin isn’t worth that cost compared to an alternative that requires trusted parties but uses orders of magnitude less energy.
«as much electricity as Chile»

Or about as much as a single large hydroelectric dam.

Fun fact: many miners are located in places with cheap hydro/wind electricity like Sichuan & Yunnan provinces in China. These provinces abandon 100+ TWh/year of hydropower. They literally run water through the dams without powering the turbines. 100 TWh/year is more than what Bitcoin consumes globally.

«single transaction has the same carbon footprint as…»

Misleading. Bitcoin transactions don’t consume mining energy. Mining power is completely independent of transaction volume.

I said “large” damn, not an average dam. But fair enough—I should have said “around as much as the largest dam”.
> Bitcoin transactions don’t consume mining energy. Mining power is completely independent of transaction volume.

I’m not familiar with the intricacies of bitcoin, but another comment claimed that the block size is limited (without hardforking) and the number of transactions per block surly is limited by the block size?

Bitcoin miners use surplus energy in remote places with lots of thermal or hydroelectric power. Remote China and Iceland. This electricity often can’t be put to any other use anyway. The price of energy is probably enough to ensure this.

Besides, the cost of maintaining Bitcoin has to be compared with holding up a fiat currency empire like the US. This requires lots of military, suppression of democracy and generally violence. Seen through that lense it might be quite cheap.

Energy transports costs are non-negligible. In fact, in Europe I pay more for the grid transfer (~0.25/kwh) than generation (0.06/kwh).
Yes, that’s one of the factors influencing planning. It will be very hard to get financing for a hydroelectric plant without existing infrastructure or some guarantee that transmission will be built. You can’t just pick a river and hope the customers come to you.
The grids are large, but the transport is very inefficient. That’s why Bitcoin mining is becoming an alternative to previous ways to avoid wasting energy surplus, like melting aluminum ore.
I understand the theory, but that just isn’t what happens in reality, at least right now. Please at least glance at the links I listed.
I did glace at those, actually read most of it. It all depends also on how much energy consumption you’d deem adequate. And further, how you even tell or know what would be adequate.

The reason is I don’t think the costs for our broken monetary system are fully appreciated, or even appreciated at all, at this point.

I can’t back it up adequately right now, but I do believe most of the environmental damage today, most of inequality, most war, and most political corruption is caused by fiat money and its skewed incentives. Crypto at least has a real shot at fixing those.

Interesting question would be, how much of _all_ energy does bitcoin cost? Now I’ve looked up the numbers. Total consumption of the bitcoin process seem to be 78-87 TWh depending on which source you look at (I found one higher than what one of your source said and will use that, for 2019).

Total annual energy consumption is 584 EJ, or 162,222 TWh (statista numbers, 2019).

That would put bitcoin at 0.05% of total global annual. I feel that is not too high.

Given your premise, I agree that is an acceptable cost. I also agree that your premise sounds difficult to back up in the space of a comment. I’ve found that most people, myself included, have some kind of pet political issue that they believe to be the real cause of all the problems in the world. I’m not dismissing it out of hand, but I think you’ll agree that it’s an eyebrow-raising claim if you’ve never heard it before.

Bitcoin’s share of carbon emissions is about 0.1% by my rough calculations (based on https://digiconomist.net/bitcoin-energy-consumption and https://ourworldindata.org/co2-emissions). My position is that stopping the worst effects of climate change is going to require lots of relatively small changes across all sectors of life. Bitcoin is nothing compared to, say, heating and cooling homes, but we can’t just get rid of heating and cooling. We can distribute more efficient appliances, build more insulated homes, influence behavior to lower usage somewhat. Each of these might give us a .1% improvement. Find a hundred things like this, and we’ve cut 10% of global emissions, that’s pretty good.

I know bitcoin is here to stay, and I’m not suggesting government should try to ban it or something because it’s bad for the planet. But until I’m convinced that it’s the savior you say it is, it’s not something I personally want to be involved in, and not something I can celebrate. Even ignoring mining, the cost per transaction is an enormous hurdle for me that I will need a lot of incentive to get over.

I can see where you’re coming from and it’s consistent reasoning. I also agree my scenario isn’t substantiated (at all) yet, even though I believe it to be not uncommon in the crypto community.

I will put my thoughts on this together, and if you’re interested ever hearing about it put some contact in your profile. In that case I’ll ping you.

This exchange turned out productive. Thanks for that.

> This electricity often can’t be put to any other use anyway.

This is false. If there is surplus electricity, prices would drop, and you could expand availability. Government, especially the Chinese government is more than capable of shaping market demand.

Furthermore, you could displace existing coal based electrical demand in the country.

The value of currency comes from trust that you manage it well, not from the number of bombers.

There exists energy where it’s not economically viable to put on a grid, or really do anything with. Many mine Bitcoin with this energy. Even in the United States. The cost of transporting it is more then the energy is worth.
In Europe where I live, electricity costs 0.06 euro for generation and then 0.25 on top for transportation to me. So eve if the grid is vast, transport costs are vast as well.
Iceland definitely has surplus energy. There’s been ideas to lay a cables to mainland Europe to export it since it’s going to waste at the moment.
Curious what percentage of bitcoin’s energy use is from surplus energy that otherwise no use?
recently Iran was blaming bitcoin for blackouts, so perhaps not all bitcoin is mined from hydro/thermal power. Of course it could that Iran was just looking for an easy scapegoat.
Our biggest environmental footprints as individuals are heating and cooling. Having an electric car is nothing compared to it. Take one intercontinental flight and again, having a fossil fuel car for a year does not exceed the emissions of that flight.

http://www.withouthotair.com/

Legitimizing Bitcoin has nothing to do with the environment in the large scale of things.

It’s like saying that you need to optimize fast functions instead of slow ones.

It’s like many environmental pushes in the US. They tackle the low hanging fruit that aren’t actually going to fix the problem.

Electric cars and low flow showers / toilets are some of the environmental steps this country takes to make themselves feel good.

For water, domestic use tends to be a small part of the US overall use, around 7% I believe. I haven’t dug further into that, but I’d imagine lawns are a big part. https://www.usgs.gov/special-topic/water-science-school/scie…

For air pollution, about 14% of worldwide pollution is from transportation. Even if we go full electric the number won’t go to zero because electricity is not free. Depending on how electricity is produced and factoring it the initial energy cost of producing batteries, we make that number smaller (maybe 7%, I’m not sure we really know). I do have worries about the amount of rare minerals that you need for batteries and how their life spans aren’t all that long. And given their higher cost to produce, they are not as economically accessible.

https://www.epa.gov/ghgemissions/global-greenhouse-gas-emiss…

If people honestly wanted to fix our environmental impact, we’d have to drastically change our habits like covid made us do. Or we just have to have fewer people on this planet.

I honestly look forward to the environmental studies that come out from how big of an impact Covid had on pollution. I think it will definitely feed our models in an interesting way.

That’s a terrible analogy! Bitcoin is a runaway feedback loop where scarcity drives rising price, which drives increasing energy usage. The equilibrium it maintains is the natural profit equilibrium where it makes sense to spend enough energy (money) to “mine” a bitcoin for anything less than the current price. But due to the built in supply decreases, that price rises, so the energy use continually increases, because there’s always someone willing to spend $9 to make $10.

It doesn’t have a stopping point, or brakes, and at each point, it is in the interest of the frog to raise the temperature of its water by one more degree.

If I was a hostile AI and wanted universe-scale civilization destruction at near zero-cost, I’d send each civilization the bitcoin “thought-bomb.” All the AI has to do is share the bitcoin discovery, perhaps anonymously. Once that is done, it puts it in the short term interest of the metaphorical frogs to boil themselves, and speed along the inevitable natural tragedy of the commons outcome.

Right now, bitcoin is like a program with bad big O math, and we are looking at it while x=2 and concluding everything is great.

> having a fossil fuel car for a year does not exceed the emissions of that flight.

That’s true (-ish).

Here are the numbers:

Modern pure-ICE cars don’t got below 100g/km of CO2. Round trip NYC-LHR yields 1 ton of CO2. So the above comment is true-ish for cars that do less than 10k km annually.

> Our biggest environmental footprints as individuals are heating and cooling. Having an electric car is nothing compared to it.

Isn’t Tesla aiming to electrify everything and then use clean energy as the source of the electricity? At the moment running heating or cooling should be clean as long as the energy is coming from a renewable source, right?

> Take one intercontinental flight and again, having a fossil fuel car for a year does not exceed the emissions of that flight.

For the entire flight, right? I would be curious how much driving one seat on a flight equates to. I presume flying is at least better than driving on a per-mile basis?

> For the entire flight, right? I would be curious how much driving one seat on a flight equates to. I presume flying is at least better than driving on a per-mile basis?

You can’t compare the two so cleanly as to conclude with a simple this is better than that. There’s different effects of different types of pollutions at different altitudes, some unknown. Brake dust, the knock on effects of needing more road due to more miles driven, the infrastructure required to operate an airport, etc.

> It’s like saying that you need to optimize fast functions instead of slow ones.

I really like this analogy

Are you basically saying that going from fossil to electric vehicles won’t make a big difference?
That’s US where everyone drives everywhere. Now we do the same for Europe or China and the effect on the whole world ends up much less.
It will make a noticeable difference but “big” is a ultimately a value judgement. Cars are small potatoes compared to industrial polluters. Huge companies that are actually meaningfully responsible for waste have been trying to put the blame on individuals for decades. Like in a tiny sense they have a point because they’re delivering products and services to individuals but they’re also pushing all the externalities of their waste onto individuals who have very little power to make systematic change while making sure that we can’t act collectively through government.

Non-energy example: trash. Jesus lord I am swimming in trash. Not because I consume in excess but because the everyday things I need come with stupid amounts of packaging that I can’t give back to them and isn’t recyclable or reusable.

Absolutely. In the large scale of things optimizing already efficient fossil fuel machines does not bring much savings compared to optimizing heating and cooling and buildings that are using that.

Not to mention the enormous amounts of energy used in manufacturing/heavy industry. China’s Top 5 emitting industries have nothing to do with transportation of individuals or farming for food, unlike some parts of the world.

There is more to the switch from ICE to electric than pure CO2 output, air quality in population centers is a big part of it too. Particulates from vehicles are a health epidemic, and whilst not all of it comes from the tailpipe it’s certainly a not insignificant amount.

I don’t disagree that heavy industry is going to be the more important problem to solve, but unfortunately I have few levers at my disposal to influence that. It’s going to take treaties, taxes, regulation and sanctions to figure that mess out. Because I have zero faith in that actually occurring, I think the real solution is going to be in remediation technologies. Consumerism isn’t going away, especially with fresh faces entering the developed world, eager to take up any slack the west gives.

Bitcoin is economically set up such that its energy consumption will follow its price. With the price at the level it is now, the energy consumption is that of a medium-sized country.

An entire country’s worth of energy is getting burned to run a network capable of a whooping TWO transactions a second.

Now that Tesla has bought these coins, they have so far driven the price up by another 10%. This will eventually be matched by an increase in carbon emissions of 10% of a medium-sized country.

This will most likely completely obliterate all of the carbon reductions that Tesla has managed to achieve so far.

Bitcoin, as it exists today, is a massive ongoing ecological disaster and probably a crime against humanity. And Tesla is now making it worse.

The amount of environmental destruction and pollution done by the farming industry or similarly land invasive industries is incomparable to bitcoin. It has an effect on so much of the ecosystem that it’s just silly to put Bitcoin in any kind of calculation with regards to environment.

Water pollution, shit pollution, river pollution, ocean pollution, air pollution, probably only the last one somewhat related to bitcoin.

You’re not comparing bitcoin to the right thing. You’re comparing bitcoin’s energy usage to the usage of a country. Bitcoin is competing against much bigger players than small countries it’s attempting to compete with Fiat currencies. The best comparison would be to compare it to the energy required to sustain the USD as the de facto fiat currency. It’s hard to get exact numbers on the DoD’s full energy usage but as some points of reference they use about 4.6 billion gallons of fuel a year, 10% of the US’s aviation gas usage, etc. To put the DoD’s usage into perspective, “The U.S. Department of Defense (DOD) consumes more energy than any other federal agency—77% of the entire federal government’s energy consumption.”(https://fas.org/sgp/crs/natsec/R45832.pdf)
I suspect it’s the air conditioning and equipment cooling of datacenters that’s the OP was referring to in regards to bitcoin’s footprint, so not entirely unrelated.
What percent of the electricity used by Bitcoin miners is generated by fossil fuels?

My impression is that most miners are located to take advantage of locales with very cheap hydroelectric/geothermal or take advantage of subsidized/overbuilt renewables. But I could be wrong. Any data on this?

If they’re on an electric grid that also has fossil fuels, then it doesn’t really matter. More clean energy to them is less to other customers, who have to make up for it with more fossil.
The weird thing here is that Bitcoin doesn’t care about whether it’s mined with clean electricity or other, and the realities of the market are pretty opaque. When people correctly point out that Bitcoin mining consumes a lot of energy, a bunch of people immediately make the claim that most of this energy must come from excess renewable sources. But there’s actually no reason at all to believe this, very little evidence in favor of it, and nothing in the Bitcoin system design that ensures it. It’s basically an article of faith — because the alternative would be objectively horrifying.

We could design cryptocurrency systems that deliberately focus on using excess renewables, or just plain use less energy for mining. But the problem is that “Bitcoin” has come to stand in for “a cryptocurrency using the specific design choices that its inventor made more than a decade ago” and so privileging Bitcoin itself makes these choices impossible. The very best possible outcome is that (small-b) bitcoin tokens will eventually migrate to more efficient consensus networks, and the big-B Bitcoin network itself will be spun down to consume less power.

I think you are a bit too pessimistic about it. Bitcoin mining is location invariant and its cost are mainly driven by energy costs, can we agree on that? We should also agree that in certain (many) locations renewable energy sources are the cheapest ones. Based on this you can also see it as an alternative store of value / money that also subsidises renewable energy demand. This drives development of new technologies and efficiency improvements due to economies of scale. Wouldn’t it be nice if you could buy solar panels as cheap as the rasperry pi foundation is able to source its arm processor (where the cheapness is also coming from an orthogonal use case with scale effects)?
Bitcoin has done shit for the environment or for reneweable energy.

I would love to see a real example where you would proof me wrong.

Nonetheless, bitcoin itself is not necssary and it doesn’t solve a problem.

People trust currencies. I trust currencies.

Bitcoin also has to have a trust system and right now it is connected to currencies. It is not decoupled. The only thing bitcoin is, its irradical and its basically gambling.

Doesn’t this argument imply that the way to stop climate change is to use as much energy as possible in order to subsidize renewable energy production?

If a miner’s power source is on the grid, it doesn’t really matter all that much if they own a hydro plant, a solar plant, a coal plant, or are just buying power off the market. Either way, they are increasing the total energy consumption of the grid and their environmental footprint is determined by the grid average emissions and the amount of power the miner uses.

If they’ve built an off-grid renewable power station, you might argue it would otherwise not been built and is therefore relatively neutral, emission-wise. I think that argument would be wrong, because of the scale of large mining operations.

If you can build new renewable energy capacity at a competitive price and at sufficient scale to power a large mining operation, that’s one thing and has nothing to do with whether or not you mine crypto with that energy. Deciding to not sell to the grid at that scale seems irrational, and honestly I doubt miners also operate power stations except maybe at a hobbyist level.

> We could design cryptocurrency systems that deliberately focus on using excess renewables

Could we? I thought Ethereum still had a pretty big digital/physical gap. In that there was no way to digitally ensure a physical truth (barring third party attestation).

It only assumes that demand is not 100% price elastic, which is almost guaranteed to be true.
That really isn’t how most grids work. There are large times where prices are now negative because of oversupply of renewables.

Mining by it’s nature has energy as its largest input cost, so it chases lower and more efficient sources of energy which are largely renewable energy

Further, good renewable sources are often poorly located for electricity distribution. You have situations where the power wouldn’t otherwise be used, so it is being tapped into Bitcoin.

Iceland has a pretty much infinite supply of clean energy with geothermal. They’re not interconnected to the grid so previously they would export that energy via aluminum, today they can export it with bitcoin and other processing (colo compute)

Georgia has also become a destination for bitcoin mining and it is largely hydro power

The reports on what bitcoin’s proportion of renewable sources vary very widely from ~75%[0] and ~25%[1]

You can debate the methodologies of these estimates all day – but one thing to note is that the worst case estimates take an emissions factor which is average _for an entire country_ – while large scale mining operations (which account for the vast majority of mining) are often colocated in specific cheaper regions, usually around hydro/renewable power

The only X factor is that a lot of energy for bitcoin is sourced corruptly. The Chinese are already some way towards resolving that (they have an incentive to!) and shut down the heavily subsidized dirty mining that was happening[2]

My main takeaway is that the trends points to bitcoin eventually becoming a lot more efficient, and potentially can be used as a regulating mechanism on grids or as a way to export energy from renewable sources that aren’t well interconnected

[0] https://coinshares.com/research/bitcoin-mining-network-decem…

[1] https://www.cell.com/joule/fulltext/S2542-4351(19)30255-7

[2] https://www.coindesk.com/bitmain-ebang-bitcoin-mining-energy…

> They’re not interconnected to the grid so previously they would export that energy via aluminum

Ok, but now somebody else is making that aluminum.

There’s always something we could do with free energy, including making carbon-neutral liquid fuels or ammonia fertilizer, or taking CO2 out of the atmosphere.

If Bitcoin were the only way to have a working cryptocurrency, there’d at least be an argument for it. Now that proof-of-stake is available, Bitcoin’s energy consumption is pure waste, since we can have essentially the same product without using the energy.

Even if that was the case, this excess power would very rarely go to waste. If bitcoin mining farms didn’t pop up, then aluminium smelters would appear instead. Aluminium is pretty much electricity in a form that can be put on a truck.
Huh? How do you get the electricity back out of the aluminium?

Oh, OK, I get it.

Region A consumes a lot of electricity smelting aluminium. Region B has cheap electricity so a smelting company moves there and ships the aluminium to region A. Region A now has one smelting company’s worth of extra electricity available.

Smelting aluminum from ore requires a lot of electricity, more so than any other common metal. It’s sufficiently high that the dominant factor in the price of aluminum is the cost of electricity used to produce it (and not the cost of the ore or transporting ore and finished product), so smelting aluminum is a relatively easy way to export electricity.
They are just pointing out that the price of aluminum production is largely dominated by electricity costs. Effectively all excess electricity can be used my aluminum producers.
You don’t. You use the aluminium instead of aluminium from a less clean source you’d usr otherwise.
Then I don’t understand how “Aluminium is pretty much electricity in a form that can be put on a truck”.
OK, so interpret my question as asking for an explanation of the figure of speech!

It’s a little bit surprising to get such pushback on a genuine question when there are substances you could describe as “electricity you can put on the back of a truck” such as hydrogen canisters and various forms of battery!

OP here…

As others have said, I was mostly referring not to the ability to easily convert to and from aluminium, but instead the fact aluminium is easily transportable and such a useful material that there is rarely surplus (if aluminium were cheaper, it would take over lots of places where steel is used, and even some uses of concrete).

That in effect means that if there is excess electricity in a region, it can in many cases work out cheaper to build a decent road to the region and build aluminium smelters than to build power transmission lines out of the region.

Aluminium plant moves to location with cheap electricity.

The electricity becomes available at its former location.

Hydro and geothermal aren’t without environmental cost. They don’t destroy the whole world but can be fairly destructive locally.

If you’re going to flood a valley, please make it for something actually worthwile.

Yes they aren’t but compared with the consumption of non-renewable fossil-fuels I’ll take the Hydro any day

Depending on the place you pick you might not even need to flood too much

Nobody is building a dam because of Bitcoin. Bitcoin is what’s done when there is egress electricity (which there always is, somewhere).
And they’re welcome to do so, as long as it’s ecological it’s not a problem. Geothermals (which the other poster is probably speaking about) are not an issue.
And yet you label Bitcoin as the problem instead of resolving the actual problem of subsidized fossil fuel.
Without bitcoin the problem wouldn’t be to be fixed as it wouldn’t be a problem.

Its also not the responsibility of the world to create unlimited carbon neutral power source for bitcoin.

Bitcoin needs to solve a real issue worth solving, which it doesn’t.

Or maybe “without subsidies damaging the environment there wouldn’t be a problem”? We can only thank Bitcoin for uncovering it, this subsidy needs to stop ASAP.

That Bitcoin didn’t solve your problems doesn’t mean it didn’t solve real issues worth solving. Bitcoin solved the problem of quickly and cheaply moving money across the world without risking it will be lost. I was unable to move money between Africa and Europe before Bitcoin, now it’s quick, cheap and reliable. Moving money between the USA and Europe also used to be problematic (took long and was expensive, at least it was reliable though), now with Bitcoin it’s very easy.

Since Bitcoin uses waste electricity (you will immediately loose a lot of money mining with ordinary electricity), it doesn’t make anything worse – of course as long as governments don’t kick the balance away.

‘waste’ electricity;

Right.

Not a single bitcoin miner in europe would use waste electricity;

China banned bitcoin mining due to grid issues;

So tell me again who has enough money to waste energy?

Bitcoin is balanced by the energy market otherwise it will deflate. IF its becoming worthless to do that job, bitcoin can’t work, therefore it will always be cost effective somehow.

This still doesn’t mean, that there is no better alternative.

You tell me who has enough money to waste energy, you’re the one claiming not a single miner in Europe would use waste electricity – I really would like to know who has so much money they continuously mine with electricity 3 times more expensive than the earnings.
This is not the point.

‘waste’ energy means energy which you could not have used otherwise.

If it is cost effective to mine bitcoin in europe, then europe will just produce more energy for your usecase independently if it is useful to do so or not as long as it is cost effective.

This is not ‘waste’ energy; Its energy prodcued for your bitcoin mining.

Would the world be better of without bitcoin? Holy shit yes.

Do you know why farmers produce opium? Not because it is using waste farmland, because others are paying them more money for it then for food to consume. Its the same issue with bitcoin.

This is absolutely false. Electricity is not at all easy (=> very hard) to store or transport, and every day megawatts go to literal waste – which is where Bitcoin miners step in. Stories about Europe making more electricity for Bitcoin miners are lies, there are few private geothermal powerplants built for that purpose and that’s it. Bitcoin mining is not some goldmine (or opium farm), it takes very careful planning for electricity costs, careful contracts and careful operation; it’s absolutely impossible to profitably mine Bitcoin using ordinary (industrial) electricity from the grid, very unlike opium farming.

> Would the world be better of without bitcoin? Holy shit yes.

Don’t speak for others. I never want to go back to world without Bitcoin. Sure, come up with something better, but no world would not be better off without it. Millions of people have better life thanks to it.

Come on… State one of your claims with hard data and not just wishful thinking.

Your bitcoin miner don’t have load control to make sure they consume the excess power. They just consume as much as possible.

And yes its still the same as opium farming; I can also give you annother example: when crops are used for biofuel, suddenly its financial better to produce energy instead of food. Happend in germany and other places.

I have NO IDEA why you would think that bitcoin mining is done by magical high intelligent controling systems. Haven’t you seen any documentation on bitcoin mining operations at all?

I mined bitcoins myself a few years back at home as well.

https://www.primafelicitas.com/5-biggest-bitcoin-mining-farm… none of them did this for using ‘waste’ energy, they all did it for th emoney.

Missusing subsidised cheap electricity and now increasing competition for energy. And there have been enough stories on grid failers in china and regulators stopping those mining farms due to this.

“Millions of people have better life thanks to it.” <<< this sentence is really weird. Are you talking about real people having a real benefit of bitcoin or are you talking about people getting rich of bitcoin by polluting our planet with unnecessary co2 and increased prices for others?

> I mined bitcoins myself a few years back at home as well.

Key words being “few years back”. I mined at home few years ago too – nowadays it’s absolutely impossible.

You can find data easily yourself, simply check what wholesale electricity costs on the exchange right now, and check what you can earn with the most advanced mining hardware – you’ll see that the earnings are three times lower than the cheapest electricity.

> I have NO IDEA why you would think that bitcoin mining is done by magical high intelligent controling systems

Because that’s what you have to do if you want to have any profit from mining in 2021. It was different in 2017, I agree.

> this sentence is really weird. Are you talking about real people having a real benefit of bitcoin

Real benefit. Bitcoin makes it easy to transfer and store money where it was previously impossible.

> when crops are used for biofuel, suddenly its financial better to produce energy instead of food

Totally false, that never was and never will be profitable. It’s only done because of EU subsidies (and these subsidies destroyed my country’s landscape and food self-sufficiency).

Yeah thats not interesting or fun to discuss with you when you just bring up thoughts and not any source at all.

It is a fact that bitcoin uses energy; There is no source of your claim of bitcoin using ‘waste’ energy.

You also assume that the ‘waste’ energy exists apparently in areas where they have fully isolated energy grids which would make it impossible for anyone else to use this energy better then bitcoin does; You ignore aluminum melting, data centers, normal households, heating etc. You ignore that energy subsidies exist to support people and are missused by bitcoin miners.

You claim bitcoin can store money, which it can do as efficiency as any other commodity out there: gold, shares, a normal bank account;

You claim bitcoin can be used to transfer money easily while ignoring that bitcoin itself has this benefit as every other exchange has; It is highly volatile, everything but userfriendly and is uncontrolled; We have a controlled money system not for the fun of it but because the rich people and unfair people tend to move money around uncontrolled; This costs you and me potentially money if tomorrow everyone would move to an anonymouse currency.

You can transfer money around the world by western union, paypal, amazon/google giftcards, gift cards, my credit card can buy in every currency; I have bought money from iran, usa, spain, japan without any issues.

And you ignore the basic fact, that bitcoin HAS TO BE MINED to be working. It HAS To BE distributed to be working. If only countries with cheap electricity are mining or a majority becomes real, it breaks; It breaks if someone is no longer motivated by earning enough bitcoins through mining as you can’t do any transaction any more. The energy price of global economys is not connected to the energy price of bitcoin directly. People will pay the transaction fee as long as they want to be able to do anything with their bitcoins.

EU subsidies where not meant to motivate too many people to make energy out of crops; Thats the exact point i was making about subsidies and energy prices. How can you not see this?

While you may not agree with the ecological trade-offs, you would be arguing against reality to say that people aren’t using Bitcoin to solve real issues right now.
Hes legitimizing crypto in general. PoS will be proven to be more efficient in almost every way, people will gravitate towards that. Bitcoin has the network effects of being the first mover right now. Ethereum is surpassing it on many metrics, txs/day, $ volume processed per day, etc [1].

[1]https://www.blockchaincenter.net/flippening/

“PoS will be proven to be more efficient in almost every way”

We’ve already known PoS is more efficient for like a decade haven’t we? When will it become real and actually start to supplant Bitcoin, 2030? It’s a very interesting theoretical point but I don’t see how it’s relevant when we’re talking about the environmental impact Bitcoin has been having for years while Tesla is dumping money into it.

You should blame Governments of the world, for holding interest rates at lower levels than the inflation rate.

eg. the USA inflation rate is 2%, whereas the interest rate is 0%.

Its inevitable that savings will flow out of fiat and into all kinds of other assets. This is the entire purpose of low interest rates – to inflate the value of assets held by retirees, pensioners, and the ultra-wealthy.

Bitcoin is unique because the supply cannot be expanded (beyond what is scheduled as rewards for miners) – unlike gold, shares, living spaces. Its also significantly more liquid and easier to transact than any of those assets because it is digital and global.

You don’t have to choose just one, single party to accept the blame. Bitcoin can be wrong even as other alternatives are also wrong.

Also, the Bitcoin supply may be limited, but the supply of new alt pins or even BitCoin forks continues to inflate every year.

I think at a certain point, the only profitable way to mine BTC will be with energy that was going to be wasted anyway.
That’s only the case if the Bitcoin price is low. Each block gives the miner a certain amount of Bitcoin, so it’s only profitable to mine Bitcoin if the cost of the energy used to mine that block is lower than the price of the Bitcoin the miner received. The higher the price of Bitcoin, the higher can the cost of the energy be before it’s no longer profitable.
Yeah it’s of course a balance. It depends on the difficulty, reward, and cost. The reward is constantly going down. I guess I just think there will eventually be a balance where it’s only possible to mine with free/wasted electricity, but maybe not.
That depends how high the BTC bubble price goes.

At a certain point, mining BTC could be the only economically viable activity to do with electricity.

Eric Voskuil writes about the “energy” argument. All moneys can be compared on energy level, and it is important to note not to look at energy solely, but also labor, land, services, energy, hardware, and other resources needed to keep a system running. If you are comparing the coin to fiat, take into account the military industrial complex, the cost of physical bank branches, physical issue, the cost of seignorage on the money holder (i.e. gain of energy for those close to the printing press vs. loss of energy for existing holders).

If you rationally examine, the money holder will select the money with the least energy waste. All moneys not held imply a higher amount of energy inefficiency. This is why one may hold the USD, as opposed to the Turkish Lira. This is why one may hold btc, as opposed to the USD.

If you want to investigate a bit more in depth, cryptoeconomics Proof of Work fallacy is a great resource by Eric Voskuil.

Link: https://github.com/libbitcoin/libbitcoin-system/wiki/Proof-o….

Missing the point. Bitcoin is the first cryptocurrency to grab attention and normalize the idea of public permissionless public blockchains in the public’s and government’s mind. Upon this foundation laid by bitcoin, other coins that use proof-of-stake can gradually take over some or most of its market share.

The alternative to your narrative is that this is promoting permissionless cryptocurrency that is hard for the government to print and manipulate, not necessarily Bitcoin per se.

Additionally, if proof-of-stake coins and DeFi can take over some of the manual paperwork done by banks, it would amount to energy savings.

Right now bitcoin is the leader and everybody knows what it is. Compared to other coins, it has a more mature ecosystem to support the needs of a corporate treasury. Companies choosing bitcoin now doesn’t mean a proof-of-stake coin cannot take over the mantle later. You can consider bitcoin to be the first coin that lands on a beachhead in the disruption of traditional finance.

For investments from large institutions and companies, I don’t think there’s any other option out there with the security and regulatory support similar to Bitcoin and with a fixed total-supply.
Institutions invest in all sorts of things without a fixed total supply. Equities, gold, and national currencies, for example.
But all those things are hedges against inflation. None of them have a precisely fixed supply like Bitcoin.

Also, institutions buy things for lots of reasons besides hedging inflation. Arguably they’re buying Bitcoin for the same reason they buy growth stocks.

Genuine question: Is it the case that Bitcoin has a precisely determined supply because the difficulty schedule is informally agreed on by all participants? What would happen if some large number of participants, say 75%, decided to change that? They simply could, couldn’t they?
If 75% of the users want something, of course they can do that. They uninstall Bitcoin, implement a new software with the new rules, and install it. This becomes the new “Bitcoin”. That is called a hard fork. You can’t prevent that because it literally means people just chose to use something else. They may even keep the name and call the new thing Bitcoin, for what it is worth.
Well indeed, that’s how it seems to me too, so I’m wondering why Bitcoin isn’t even more fiat than fiat.
Not only is it possible, it might eventually be likely. The supply schedule assumes that transaction fees will be sufficient for security, but researchers have cast doubt on that assumption:

https://freedom-to-tinker.com/2016/10/21/bitcoin-is-unstable…

If some future generation of bitcoiners is faced with either increasing the reward or putting up with frequent large rollbacks, we can’t really predict which they’ll choose.

This is true, they could hard-fork the chain and make that the new Bitcoin but this is where a bit of Game Theory comes in – why would the network collectively do something to harm it’s own self? Bitcoin miners are incentivized to keep up the security AND stick to the 21 million limit laid down by the Bitcoin Whitepaper. If hypothetically the network decides to change the limit, I believe that would just destroy the Bitcoin narrative and so no miner would even agree to do that.
Somebody should tell Elon about NANO if he is serious about the environment and wants a real digital money system
“Legitimizing Bitcoin more than offsets the environmental benefits of electric vehicles.”

Not in Iceland.

Not going to defend Bitcoin POW, but that’s some world class Tesla FUD right there 🙂

First, I think JPMorgan, GS, MicroStrategy, Grayscale, pumping billions into BTC this year and the OCC announcing that banks can use blockchain for settlement probably has more to do with BTC being viewed as legit than TSLA jumping on board as a tech company.

Second, about 25% of energy is consumed in passenger transportation and Tesla is pretty much single-handedly moving the world to electrifying that making it a) 5x more efficient, b) possible to run from renewables.

Third Tesla is the only organization in the world ramping up to do planet-scale battery production that will make it possible to transition all energy production to renewables. (If people want to pay to produce and consume clean energy for arbitrary purposes that’s fine by me… as long as they don’t kill me in the process).

The idea that Tesla’s influence on BTC mining will waste more energy than their electrification efforts have saved and/or redirected to renewables is nutty.

Good thing you are only pretty sure then because it’s entirely false. Bitcoin needs several orders of magnitude more energy per transactions.
Both sides of this arguments are oversimplifications to the point of being meaningless.

Specifically: L2 like lightning, settlements on sidechains, and other things I won’t go into here.

The long and short of it is that it’s incredibly hard to quantify and compare and I am yet to see an attempt that gives any meaningful insight.

If Bitcoins proof-of-work and the consequences it has becomes a net loss or net win in terms of climate is a very open question. I would love to see more analysis of it but it’s really not obvious either way.

Lighting is dead on arrival, and can not possibly scale. It will never amount to anything. It is relying on people finding solutions to routing problems that nobody even knows how to begin tackling.
As someone who has been following the development closely and run nodes for years; you are very, very wrong.

Adoption has been extremely slow and the two main implementations (lnd and lightningd) are far from complete and feature-compatible, even if development velocity is actually very high in both.

There are serious efforts in development to improve on all the current problems, and relatively seamless interoperability and liquidity bridges with L2 networks on other chains like Ethereum is IMO the coming key to make it happen for real.

In practice it should not be necessary for a retail user to run or maintain their own always-on node(s) in order to get the benefits in a secure way – but much of the required plumbing is still in heavy development.

It’s OK that it takes time. Maybe it’s another 5-10 years until you will be able to appreciate it – I think it’s shorter than that but time will tell.

TLDR lightning hasn’t fully arrived yet and it will continue to happen gradually

There is no way to implement routing in lightning. Literally nobody knows how to do it. It is a studied problem, and nobody has a solution. Nobody knows where to start looking for a solution.

It doesn’t matter how much is fixed or tweaked in the code, it won’t help. We don’t know how to solve routing in Lightning. It’s just not a tractable problem.

Care to elaborate exactly what you mean by that? Routing seems to work well for me at least
It works now, because the network is tiny, the number of transactions are low, and the implementation uses a dumb brute force approach.

That approach does not scale, at all. If Lightning were ever to grow beyond a toy network, it would completely collapse.

I would be very curious to learn more about this – do you have any sources for it or links to conversations around it?

(It’s not commonly recognized and impossible to talk about without any pointers as to where the problem should lie)

Thanks. This I’m somewhat familiar with, it’s a theoretical fundamental issue in any decentralized and distributed routing network so applies for any interesting L2 solution.

In practice this needn’t be an issue:

* Most nodes will rebalance, open and closed channels based on neighbour uptime and reliability

* In practice the LN network is expected to have a little but of a hub-and-spokes topology. So in practice you will almost always have a couple of well-known highly connected peers along your route

So it’s a fundamental issue that will become a reality in worst-case scenarios but something that can be mitigated.

As one of the comments noted, we’re somehow able to do this for TCP and TOR.

You linking to the /btc subreddit makes me think nothing anyone says or any developments will ever convince you (correct me if I’m wrong). In that case, I think your efforts are better spent in focusing on bringing value to the efforts you do believe in rather than telling others they’re bound to fail.

100% this. I work at a merchant that accepts Bitcoin for payment, and 90+% of our volume comes in over lightning (a layer 2 solution built on top of Bitcoin).
These layer 2 solutions lead to centralization and make some nodes more important than others. The fact that most cryptocurrency enthusiasts tend to brush this under the carpet shows that it’s more about getting rich than some ideological fight against the banks. Cryptocurrency developers are slowly but surely reinventing the banking system, just less efficient and less regulated.

Then there’s the question of whether a deflationary currency can even work in the first place.

I don’t think that Bitcoin or any other crypto asset needs to become the main currency of any country. They can live as tertiary assets with valuable properties, that can facilitate trade or act as collateral for certain contracts, without being declared a currency in any geographical jurisdiction.
What’s the real difference between a layer on top of BTC (effectively a new currency backed by BTC) and an existing currency backed by traditional things like gold and international treaties?
I mean, he spells it out, but it is doing 1/1000 the value.

And if you make that comparison, how much energy is being used to run Fedwire? A few kilowatts maybe?

The security of the US financial systems is maintained in part by the US military which is not exactly free either
There are other alternatives to BTC, which are more efficient in terms of energy usage, more effective in terms of transaction speed and transaction fees.

BTC is a cryptocurrency, but not equal to cryptocurrency for the sake of this discussion.

BTC is arguably not effective as an actual medium of exchange. Many BTC maximalists have retreated from the actual currency use case in favor of “store of value” arguments.

I really like Nano, the whitepaper is pretty easy to read, they seem reasonably good and sending money is instant (sub-second). Pretty great for a currency that’s meant to be used, rather than hoarded.
Take your pick: https://coingecko.com

While many of these are forks of Bitcoin and use similarly wasteful proof mechanisms, many are also completely new and different. Several different consensus mechanisms are broadly used across these, most of which improve drastically on Bitcoins wasteful Proof of Work (PoW). Some even solve the problem with only very negligible energy footprint, such as the variations on Byzantine Fault Tolerance (BFT). It’s been long-debated whether those alternatives trade safety for energy-savings, but after many years it would appear the reverse is true. The majority of projects that have succumbed to some kind of system-inherent weakness have been PoW protocols being “51% attacked”, which is generally not a concern for the alternatives.

Depends on the use case. If you want to pay anonymously online then there is Paysafecard for example (available in some countries and for some services).

There are other blockchain currencies of course, but I think they all have the same environmental issues.

Ethereum, but it still relies primarily on Proof of Work, with Ethereum’s Proof of Stake Beacon Chain currently in the first phase of its launch, and not being used to secure transactions.
Maybe, if you completely disregard everything else that Bitcoin puts on the table, and how much energy is required to sustain the infrastructure it will make obsolete.
Highly likely a used petrol car will be bought by someone even if not by you personally, so not a fair assessment.

A fair assessment would be a new BEV versus a new petrol versus a new diesel versus a new hybrid.

This isn’t how markets work. Your argument is basically equivalent to the old “my vote doesn’t count” line, but yet still different people get elected over time.

It’s not about whether you or I buy a used petrol car over a new EV; it’s about whether you & I buy a used petrol car over a new EV.

Emphasis on the environmental efficiency of new products in general over the environmental impact of buying new in the first place is a topic that’s well worth highlighting.

I do not understand your thought process.

Cars enter the world by being made, not by being sold. They leave the world by being damaged beyond economical repair, not by being bought.

This is not the same as party politics, even though literally every election and referendum I have voted in would’ve resulted in the same winner had I not voted. The political comparison would be voting ex-politicans off X-Factor or Strictly Come Dancing or $COUNTRYs-got-talent etc. (second hand) versus current politicians in elections (new).

They don’t get made if they won’t be sold. So if enough people didn’t buy them, they would stop making them. Similarly, if enough people participated in voting for real change, perhaps we would see it.

That’s the argument anyway. Personally, I think such coordinated effort is too hard to pull off because you are up against highly sophisticated media campaigns paid for by politicians and industry.

Surely it’s more credible that activity in the secondary market stimulates the primary market, than that it doesn’t.
You should compare like for like. Second-hand BEV vs. second-hand ICE, or new BEV vs. new ICE. Mixing them means you’re putting all the market boosting on one product category and all the market reductions on the other category.

To put it another way: how would you react to a study which compared the environmental cost of a second-hand BEV to a brand-new ICE?

Depends on what the study is trying to prove. You seem to be angling for some sense of “fairness”, as if this is a game where EV / ICE “compete” and we want the rules to give each side equal chance or something like that. This isn’t sport; if you’re doing a scientific study you only care about getting the correct answer to your question.

If your question is whether a second-hand BEV has higher / lower environmental cost, why would there be a problem doing such a study.

It’s not a foregone conclusion either; e.g. (hypothetically) a lifecycle analysis could show an EV to be less optimised for long-term use (spare parts environmental cost, etc.), compared to a new ICE with a more sustainable long-term maintenance story. This might be unlikely but you can’t find answers to these questions without such studies.

The original claim was “All EV’s are worse for the environment than buying a used Petrol car”. If your claim is that buying a used EV will be best of all then that seems reasonable.
> They leave the world by being damaged beyond economical repair

Sadly, this is not the case. For most products.

> It’s not about whether you or I buy a used petrol car over a new EV; it’s about whether you & I buy a used petrol car over a new EV.

Was something supposed to be different there?

Also possible that if you buy the used petrol car then the someone else who would have bought it will buy a new one instead, ultimately stimulating the production of more new petrol cars.
> Highly likely a used petrol car will be bought by someone even if not by you personally

Well when the government gives people $3 billion to smash their used vehicles (C.A.R.S in 2009)rather than keeping them in the used market, it does tend to cause more new vehicle purchases.

I’m not disagreeing with your point that people will eventually buy a new car if used ones aren’t available, but if every vehicle was kept on the road for 25+ years, it would lower demand for new vehicles.

I’d forgotten about that. That certainly seems suboptimal, from an environmental point of view.
Tesla’s mission is to accelerate the adoption of renewable energy sources. This doesn’t directly counter that. In fact you could argue that pushing the world to rely on massively energy-inefficient proof-of-work rather than a centralized authority for trust in the financial system is going to make the need for renewables even greater.

If (and it’s a big if) we can get to 10% renewable energy in the next decades, Bitcoin’s energy consumption will be much less of an issue.

There is no lack of demand for energy. The world is absolutely ravenous for energy. The reason we don’t have more renewable energy is absolutely not, in any way, because of there not being a big enough demand for energy.

No, what Tesla has done here will instead wipe out all the gains in reducing carbon emissions it has managed so far, out of pure greed.

This is a disaster.

The energy cost of running the bitcoin network is ~constant in relation to the number of transactions processed.

Cost of running the network also goes down with time as fewer bitcoins are issued as block rewards.

It goes up with the price of bitcoin, as more miners spend electricity on mining.

Those things have historically led to increased energy costs for the network, but in the future they could well lead to decreased energy use too.

I always understood that there is only a limited number of transactions in each block. So higher transaction number = higher block number needed and therefore likely higher competition and higher transaction cost.

This means that more blocks needed = more miners motivated to mine.

Does the higher number of ‘failed’ mining not also increase with the number of miners?

And proof of work increases with each block does that not imply higher energy cost per mined block?

> I always understood that there is only a limited number of transactions in each block.

Correct.

> So higher transaction number = higher block number needed

No. The rate blocks are made is fixed (on average), and that limits the total transaction capacity of the whole network. That’s why people are working on things like the Lightning Network as a way to add more transactions.

Other efforts to either have more blocks per hour or more transactions per block have (mostly) failed.