Buying a Tesla car in Bitcoins cancels 4 times the CO2 savings for its lifetime | Hacker News Reader

Buying a Tesla car in Bitcoins cancels 4 times the CO2 savings for its lifetime

franck-leroy.medium.com

171 pointsFranckLeroy113 comments

Lol, that the author isn't accounting for Bitcoins being used more than once makes this comparison one of the most laughable "bitcoin is too energy inefficient" arguments I've seen yet.

This is basically like saying, "If you only account for the first passenger on the bus, busses are way less efficient than everyone driving their own sportscar!".

Each subsequent transaction still uses a significant amount of energy, no?

Yeah, a better comparison would be energy usage per transaction, and completely disregard coin creation as a distinct kind of transaction (fundamentally, coin creation is just another transaction in the block).

There are still many caveats and nuances when analyzing this number, but at least it would be a valid comparison.

The miner hash power secures the blockchain and is independent of transaction rate.

Increasing the transaction rate does not require any additional energy expenditure and transaction rate (block size) has already been increased twice since Bitcoin's inception.

Dividing the total power consumption of bitcoin by the relatively small transaction rate makes for good headlines so I'd expect it to continue even though the two are unrelated.

It's ironic considering the articles he links at the end actually hold more water:

https://digiconomist.net/bitcoin-mining-more-polluting-than-...

Gold mining is less energy intensive and produces more value.

And they verify many transactions each time they mine a block.

Still, how much energy would it take to print an equal amount of money in the form of banknotes?

How many people are buying a Tesla in cash though?

as a data point: the entire Bank of Italy consumes around 700Mw/year, 100% of them comes from renewable sources since 2015 (vs at least 100Tw for bitcoins, it's 140 thousand times less energy).

the whole Bank of Italy emits 14.8 thousands tons of CO-2 a year, the equivalent of buying 185 Tesla in bitcoins.

More energy than printing 100x that quantity of Bitcoins on your own private chain

Are there any good papers on the BTC network robustness in the event of war.

It is well known that major military powers have the ability to cut essentially every ocean-floor optical fiber bundle handling the backbone of the internet at a moment’s notice.

If this happens, how would the bitcoin network respond without active connections to other mining nodes?

E.g. would the Chinese miners automatically (algorithmically) decide that they are the only existing miners, and so on and so forth?

Would an act like this essentially fork bitcoin into country segments because each communicating sub-group would think they have the ground truth until the global internet is physically reconnected?

Would love to see a simulation of this.

This was actually one of the reasons Bitcoin Core devs were opposed to raising the block limit. Bitcoin requires very little bandwidth (around 1.5mb/10minutes).

You can actually get the Bitcoin blockchain from Satellite for free: https://blockstream.com/satellite/ However, as I understand it, it only allows receiving and not transmitting data.

>However, as I understand it, it only allows receiving and not transmitting data.

what about something like shortwave radio? You probably can't have everyone transmitting at the same time, but a few stations around to world can broadcast/relay transactions across pockets of connectivity.

Very interesting thought. I believe that chains would initially split, effectively being forks of each other. However, the consensus algorithm of Bitcoin dictates that the chain with the most work is the valid one, meaning that in the event of a "reconnection", one of the chains would be abandoned (and everyone would agree which one to keep, namely the one with the most work).

In the case of a total disconnect between countries, there is no other way than splitting the network. If partial connectivity exists (using satellites for example), transactions could still be broadcasted from one country to another. However, the same coins could be double-spent in your own isolated network as well... until a reorg happens upon reconnect.

Philosophical question: At what point do divergent chains become irreconcilably and separately valid?

Is this a property we would ever want in a should-be decentralized currency?

One way this can happen today is with intentional forks.

That is actually a good and very practical question.

I think it reduces to the chains will always have to be reconciled because you would otherwise open yourself up to N% attacks where N is whatever threshold you decided was "safe.'

I'm guessing that when they all reconnect again the longest chain would win and basically all the other forks would roll back, so essentially only the transactions of the continent with the most hash power would stay.

IIRC bitcoin does not have any conflict resolution besides "most work wins".

But won't each continent adjust its difficulty to account for its local hashrate? And would a high difficulty fork accept that a low difficulty longer fork is valid? Or would it reject it for having invalid blocks?

The algorithm is tuned so that a block is mined about every 10min no matter what the hashing power available is. In the case of a serious and persistent network partition, both “sides” would continue to mine blocks at roughly the same rate as before, minus the first blocks that would take a while as the algorithm tried to catch up to the drastically reduced local hashing power.

The real issue is what happens once the partition is healed, and it’s not a technical problem. The technical solution is straightforward: longest chain wins. The real issue is a social one: how do you deal with finding out that the last N months worth of transactions are just gone?

> The technical solution is straightforward: longest chain wins.

One caveat here is that "longest chain" is measured not in blocks but rather in cumulative difficulty. So the fork with more hashing power, having a higher difficulty per block, will mine a "longer" chain over the same time period.

> The real issue is a social one: how do you deal with finding out that the last N months worth of transactions are just gone?

If the transactions are still valid (i.e. the inputs haven't been spent in diverging transactions on both chains) then they can be reintegrated into new blocks on the winning fork after the partition heals.

The real problems come from double-spends, whether deliberate or accidental; if funds were moved from TxA to InB in one chain and from TxA to InC in the other then only one of these can be retained, and all transactions downstream from the losing version will be nullified.

In general, to create such a situation a client would need to be aware of both forks and sign conflicting transactions for the same unspent output. There is one major exception, however, which is that the coinbase transactions introducing new block rewards on the losing fork can never be valid inputs for transactions on the winning fork. Ergo, any transaction which depends on recently mined coins is ineligible for reintegration.

If I'm stranded in Antarctica, and decide to compute hashes with my pocket calculator to pass the time, and drop the difficulty to zero (because I can do one hash every 10 min, so they all have to be winners), does the bitcoin protocol say that my chain of empty blocks is a valid contender for longest chain? Or does "longest chain" also take into account difficulty? (Setting aside the obvious fact that in reality everyone would obviously just ignore me)

This isn’t quite how the algorithm works.

To make a valid block, you have to start with another valid block. The difficulty is set (edit: I was wrong, and I fixed this) every 2016 blocks based on how long they took to mine. This works out to about 2 weeks at the expected rate of mining. The average time of those 2016 blocks is then used to calculate the difficulty of the next 2016 blocks, and the difficulty is marked down in the chain itself.

So in your hypothetical you’d have to solve around two weeks worth of blocks at the current difficulty level, which isn’t possible in a human lifespan. After that the difficulty for your chain would rapidly fall, but your sub-chain would already be very far behind and would never catch up.

That makes sense, I remembered that it adjusted every 2 weeks, but I forgot that the 2 weeks was actually measured in blocks, not wall time.

In practice you wouldn’t be able to mine at all, because the difficulty updates infrequently, so you would have to mine several blocks at the old difficulty. Obviously this is impossible on a pocket calculator.

I’ve always assumed that the notion of longest chain takes difficulty into account, although I haven’t really been able to find confirmation of this.

> It is well known that major military powers have the ability to cut essentially every ocean-floor optical fiber bundle handling the backbone of the internet at a moment’s notice.

I'm not doubting your statement, but I would love to hear where you got that point from, since it seems really interesting.

I hope mesh networks and satellite internet connections are robust enough to counter this.

I think starlink is up and would provide the secondary line.

- I think 80 tons of CO2 for BTC is wrong. It should be around 15-20 tons (75% of BTC is mined with renewables, I think approx 20-25% is coal)

- for US, CO2 per $ GDP should be around 0.3 kg

- so if BTC is 50000$ value, it is almost same CO2 then something else US produce, (it would be 50000* 0.3 = 15 tons)

- if we assume those numbers correct, lets assume they are both 15 tons, it means 50% of the things US produce is less carbon friendly for environment than bitcoin.

- also BTC will be reused ( it is on article though )

Renewables don't exist in a vacuum: "Green" miners buying up capacity drives up the price, driving others into non-renewables as a consequence (if only temporarily).

Until we are at 100% renewables, supporting a more energy-consuming product/solution/process while alternatives readily exist should not be called "green", in my opinion.

Bitcoin mining operations are generally located where electricity is cheapest. Electricity is cheapest where there is a surplus of hydro power (or other power with very low marginal cost). Where there is a surplus, use of that surplus does not drive other customers to other power sources.

By that logic, Bitcoin disincentivizes any investment in better grids and more efficient energy storage.

Also, any such mining rig could have reasonably been a data center or scientific supercomputer instead.

>could have reasonably been a data center or scientific supercomputer instead.

Which would have been used for what? Supercomputer centers are having difficulty selling their cpu cycles. A data center for what? Figuring out how to better serve ads?

Before you say protein folding, I was in on meetings where s major pharma company was considering decommissioning their computational data center in the bay area because it was underused and the real estate was worth too much to leave on the table

I think your second point here often gets missed/understated. That energy and those computers could have been helping forecast severe weather events or working to fold proteins or any other number of useful tasks that don't involve tracking a ledger of other people's wealth.

The energy perhaps. The "computers" aren't. They're just ASICs that can calculate hashes at a phenomenal rate, they're not general purpose.

And the argument about energy isn't straightforward either. Most bitcoin mining sites are set up where there is an excess of energy - when I had miners a while ago, I used a place in Newfoundland, Canada to host them, because of the local hydro dam. The water falls through the sluices or goes via the generators, it's just based on demand.

>The energy perhaps. The "computers" aren't. They're just ASICs that can calculate hashes at a phenomenal rate, they're not general purpose.

The chips are made with recent-ish nodes, so the silicon/fab capacity could theoretically be used to make CPUs.

edit: looks like at least one bitcoin ASIC maker is using TSMC 7nm, the same process used to make AMD CPUs.

[1] https://blog.bitmain.com/en/bitmain-announces-next-generatio...

That's not "logic", that's reality. What you said is pure speculation.

Indeed, speculation offering a counterpoint to the implicit assumption that renewable energy used by Bitcoin miners would not have any capability of impacting the energy market when used more efficiently.

Doesn't that take away from useful aluminum production?

> Renewables don't exist in a vacuum

Yes they do, like all energy sources there's a physical limit on how far you can transmit it, all power generators live in a regional bubble.

There's a reason all that excess hydro energy in Sichaun province goes into negative prices multiple times a year and can't be bought elsewhere in the country or even exported to other countries, it's simply too far away.

> it's simply too far away.

Brazil has a 2500 km long ultra high voltage direct current line running from a hydroelectric power plant to Rio de Janeiro. I'm pretty sure there's a medium-sized city or two within that radius of Sichuan.

That's the longest in the world, not exactly representative of the norm. There's grid bubbles everywhere, they do all live in a "vacuum", you can't just magically transport it without decades long mega infrastructure projects to build super grids and accepting large transmission losses.

GDP is a very questionable metric. Burn down your house, buy a new one and you have contributed a great deal to the GDP of your nation. If a cat. 5 hurricane makes landfall and destroys thousands of homes which have to be rebuilt, the GDP increases. That way a little bit of global warming raises the GDP (of industrial nations).

Another perspective then, worldwide bitcoin co2 emission is less than residents of Tampa, FL, which has less than 0.1% of US population

Bitcoins emission is big, but in the bigger picture it is not that much at all.

US military emission alone should be like 200x bitcoin alone

With an estimated 178TWh/a electric energy dissipation for bitcoin mining and 0.416kg CO2 released for every kWh electric energy produced in the USA and 15500kg CO2/a per capita released (total, not just for electricity) in the USA, the CO2 released from bitcoin mining corresponds to the release of about 27 million citizens of USA. Not sure why the residents of Tampa would release so much more.

From the article energy usage is around 77 Twh according to article ( actual number can be around 100 TWh now) Which 75% is from renewables. That leaves us around 20 Twh, 8k tons of CO2 (10k for 100Twh)

Tampa has population around 400k each emitting 15 tons, 6.2k tons.

As I said emission of bitcoin is big, but in total it is very small percentage.

>I think 80 tons of CO2 for BTC is wrong. It should be around 15-20 tons (75% of BTC is mined with renewables, I think approx 20-25% is coal)

80 tons is already the lower estimate. The upper bound is closer to 200 tons.

That last point is key. Bitcoins once created exist forever.

But obviously people will by then move into NewerCoin (TM) . Would there be _any_ reason, considering the primary motivations and utility behind bitcoin, not to do it?

Until somebody loses their wallet in a discarded HDD.

Yes and every transaction henceforth incurs an economic cost. The gift which keeps on giving.

If they dont get lost, forgotten or seized to be destroyed.

The average is not the median.

true but you don't need median here:

if you produce 1 hammer, 1000 nails. average thing produced is not 50% chance hammer, 50% nail, it should be weighted.

The difficulty of mining bitcoin is variable, whereas for gold it is (comparatively) constant. The energy cost of creating $40,000 worth of bitcoin right now is very different from the energy cost of $40,000 worth of bitcoin having been created.

It is estimated that 190,000 Tons of gold have been produced in history, which is 53.8 years worth at current production rates. That current production rate requires 132 TWh per year, so the total cost of producing the gold in circulation should be approximately 7100 TWh.

The total power consumption of bitcoin has been approximately 370 TWh. The market cap for gold is approximately 11 times higher than bitcoin's, but that would still only be 4070 TWh when normalized. On average that's 0.37 kwh per dollar of bitcoin mined to date vs 0.64 kwh per dollar of gold mined to date.

A good share of the gold mined is not in circulation. Besides other uses, the bond wires of every chip are made out of gold.

Bitcoin is "the gift which keeps on giving". Every transaction, not only the original "mining", incurs a substantial ecological cost.

The share of gold otoh used as financial tool is often not moved at all in transactions. E.g. a good share of it is stored in some vaults and virtually never moved. Most of Germany's gold was store in Fort Knox for more than sixty years, see https://www.ft.com/content/4edf00ee-a43c-11e7-8d56-98a09be71... .

And plenty of bitcoin is not in circulation, but that is irrelevant. The comparison is between the ecological cost of mining bitcoin versus mining gold.

Like gold, bitcoin does not actually have to change hands to be used. If people deposit bitcoin into a virtual vault, they can exchange it with eachother all day long without anything being processed on the network. It's only when someone withdraws their bitcoin from that vault that they need to process a real transaction - equivalent to physically moving gold. The difference between bitcoin and gold is that the environmental costs of transferring value by gold increase with distance and quantity: it takes a lot more to ship a ton of gold around the world than handing a coin to a person next door. Bitcoin, on the other hand has a fixed cost - the transaction to buy a pizza is no different from the transaction to buy a pizzeria. Of course you're not going to wire a bitcoin to the local pizza boy, you're going to go through an intermediary that provides a lower cost transaction. You use bitcoin for the big transfers where it is competitive both financially and ecologically with transporting similar value in physical assets.

Not every chip, copper is used too. The automotive semiconductor manufacturer I used to work for was transitioning to copper.

Ironically in his recent appearance on the Joe Rogan Experience podcast Elon Musk spoke about about the need for a CO2 emissions tax to price in that externality.

https://open.spotify.com/episode/2aB2swgyXqbFA06AxPlFmr?si=j...

As far as I'm concerned, this is equivalent to the statement that "refrigerating beer causes the ozone layer to fail".

There was a time that it did, and then we banned CFCs, and now it doesn't.

Shouting at people about CO2 is simply never ever ever going to fix the problem. It needs to be incentivised or it won't happen.

Not to mention individuals aren't even the cause of creating most of the greenhouse gas volume behind climate change. It's massive corporations creating something like 90% of all greenhouse gasses? 100 of them create 71%

(https://www.google.com/search?client=safari&rls=en&q=corpora...)

So when Shell and BP are on Twitter sharing ways to change your behavior to save the environment, it's like the murderer encouraging you to wear a lucky charm to prevent being murdered, as they're standing over you with the knife.

>It's massive corporations creating something like 90% of all greenhouse gasses? 100 of them create 71%

And why are those corporations emitting Co2? For the fun of it? Because it generates profit for them? No, it's a means to an end for them, which is producing products that ultimately go to consumers. On the flip side, if you're a consumer and 80% of your co2 emissions are indirectly generated by corporations working on your behalf, you don't get absolved for that 80%.

Great, now you have two parties who both don't think they are responsible for the problem. Customers blame companies. Companies blame customers. Nobody thinks about the real problem which is the fact that governments are allowing the continued subsidy of CO2 emissions. You can't expect a system that is built around incentivizing CO2 emissions to reduce CO2 emissions for the sake of charity.

Unless individuals change their purchasing behaviour, big cooperations will have little incentive to do anything different. It's the same as "blaming" China for high emissions while still buying products manufactured under these conditions.

The question is where to source alternatives. It is significantly harder to find products from alternative sources. For some products, the only solution is DIY.

well, if only we hadn't have forgotten that corporations work for the people, imagine the world we could live in.

This is very very misleading. That bitcoin won't be used just once. After you give it to someone, they will use it too.

Which would be more compelling if Bitcoin weren’t hoarded and were actually usable as a currency.

You mean like for purchasing a tesla?

when did it happen?

> That bitcoin won't be used just once.

Which will incur further fees, compounding the problem. (Admittedly, the fees are usually much lower than the value of the coins transmitted in a given transaction.)

If I wanted to mine a bitcoin to buy a tesla that is going to use some electricity.

We need a significant worldwide CO2 emissions tax to get rid of the POW coins and replace them with something vastly more efficient.

Bitcoin is unable to evolve due to lack of consensus. The only constant is change. If bitcoin is unable to change it will die.

But how else will we get rich without doing any work?

You can still pump the new coins, you just won't need to create megatons of CO2 in the process.

You can buy stocks. The company you are investing in can do the work on your behalf.

OK then go ahead, what's your vastly more efficient solution?

It seems that Avalanche consensus is a strong contender, isn't it?

PoW isn't going anywhere. CO2 tax would just push more mining to renewable, which 80% of it already is. This is all FUD.

POW is taking renewable energy away from other consumers of electricity.

This is how insanely bad Bitcoin is for the environment : If you buy a Tesla car (around 40 000 $) in Bitcoins, the impact of the mining of those bitcoins is around 80 tons of CO2. This is 4 times more than the savings of CO2 you can expect from this car (compared to a gasoline one) on its entire lifetime (around -20 tons).

It's not a problem of Bitcoin but the reality in which there is no cap on externalities.

Every sane person will try to limit consumption/waste of critical resources if she knows the resource is limited. It's an easy choice to make.

Do I take bath if I have just a bottle to drink while being lost on a desert? Do I keep car engine on in a garage?

For our convenience, any side effects of our consumption are hidden from us. We don't have to kill our bacon, keep waste at home, or enslave children to drink our cocoa. Occasionally we will shed a tear while watching a documentary about lovely, furry animals with sad eyes.

It's true that if we just put a tax on CO2, then either the price of BTC would go up, or the work factor would go down.

However, that seems to be less politically feasible than banning BTC.

This seems flawed. A single Bitcoin can be split into 100,000,000 pieces and spent infinitely. It may cost some X amount to mine it, but that is not an ongoing cost.

Yes, a more precise value would arguably be the CO2 impact of mining associated with the transaction fees, together with some fraction of the "mining cost" of the coins spent.

This is all FUD. Miners largely use renewable power that is excess, not expensive dirty power plants.

Here's a good breakdown of the counter argument: https://twitter.com/yassineARK/status/1360343382556483587

This is not how power grids work. Renewables have priority over dirtier peaker plants. If you turn off bitcoin mining, the average CO2 per kw emitted by the grid goes down.

Electric power is fungible. Any renewable power used for Bitcoin is power that cannot be used to offset carbon emissions.

It is not. Transmission is not perfectly efficient, so location is extremely important. Hence why energy markets have varying prices in varying locations.

Location is somewhat important. Losses in a high-voltage direct current power line are around 3% per 1000km.

The author seems to have a conflict of interest, do you have additional analysis or proof (ex: peer reviewed papers)?

Articles like this while well meaning and coming from a good place are extremely naive and myopic. Do a bit of research in terms of the costs in lives and “, yes c02, of the current status quo and petro dollar complex. Do some research on how many human productive hours where lost in debasement and irresponsible monetary policy (fun fact the GFC cost around 70,000$ per American) I can go on forever and should you be interested id be more than happy to point you in the direction of sound research that has been done on this topic rather than this click bait

These comments are worthless if you don't have the receipts to back them up. Be better than the rest of the internet.

https://climateandcapitalism.com/2008/03/19/global-warming-a...

https://hbr.org/2018/09/the-social-and-political-costs-of-th...

https://www.bloomberg.com/news/videos/2021-02-09/what-people...

Happy to offer much more if requested

None of these are peer reviewed journals

And what about the CO2 impact of using traditional banking (air conditioning, heating, commuting...)

What about the people commuting to the factory producing the cpus used to mine bitcoins, what about the people commuting to the car factory producing the cars of the people commuting to the cpu factory ? &c. We can play that game for a long time and nothing of value will be written

Because you don't want to "play that game", so you can just assume the financial infrastructure costs zero? Is this how you "play that game"?

It's definitely not zero, but I don't know any process in the financial industry that explicitly incentivizes wasting electricity.

If business class tickets become cheaper, financial analysts will not start buying more plane tickets. Bitcoin miners on the other hand will start mining twice as fast the second the electricity price drops by half.

It also doesn't seem like Bitcoin stakeholders are remotely interested in transitioning the system off proof-of-work and towards less wasteful alternatives, or even just making it more tractable as a retail payment system.

> I don't know any process in the financial industry that explicitly incentivizes wasting electricity

Inflation. If you don't spend your money, it loses value. This is actually part of the economic program (inflate to grow demand). What are you going to spend it on? Stuff or sevices. Stuff takes electricity to make. Services take electricity to perform.

You could also invest, but that's also just indirectly incentivising stuff and services, except in a trickle down fashion (put money into the corporation that's gonna do these things).

Bitcoin may be wasteful, but, its energy cost is explicit and not hidden, which is why it's attacked.

>Inflation. If you don't spend your money, it loses value. This is actually part of the economic program (inflate to grow demand). What are you going to spend it on? Stuff or sevices. Stuff takes electricity to make. Services take electricity to perform.

How does spending money on clean energy infrastructure produce CO2 emissions? Obviously there is a trace amount because we are dependent on a CO2 based economy but in reality if the incentives were correct we would be able to increase spending without additional CO2 emissions.

The problem begins with the fact that the central bank is distributing the fresh money in a way that drives Bitcoin up. So yes, we could argue that the central bank is directly responsible for the CO2 emissions of Bitcoin and the system itself is what's broken. Bitcoin is just the symptom.

Bitcoin is 0.5% of global energy usage. https://cbeci.org/cbeci/comparisons

Is it 1/200 of global financial activity?

Coindesk indicates that bitcoin had 25 million transactions versus Visa having 50 billion transactions. So that is 1/2000 [https://www.coindesk.com/what-bloomberg-gets-wrong-about-bit...]

If Visa had a similar energy efficiency to bitcoin, the energy use of Visa alone would be larger than the current global energy use.

This rules out unaccounted dependencies hiding a larger energy use than reported for the financial sector that would put bitcoin on a more even footing, even when you count things like "the US military" or "extracting oil to fuel cars" as an energy cost solely existing for the financial sector.

Mastercard just uses a Postgres database cluster which is significantly less computationally expensive than bitcoin. And it scales better.

Is there any evidence that Bitcoin is actually displacing traditional banking?

Using BTC for your savings or checking account would be an absolutely terrible idea given its volatility. No rational person would ditch traditional banking in favor of Bitcoin.

So really, this is just whataboutism to deflect from the fact that, environmentally speaking, Bitcoin is one of the worst inventions of the century.

The "Volatility" is purely temporary because of the market still being built. Eventually, the limited supply will make the currency super-stable and make calculations of actual worth of something super-easy. https://youtube.com/shorts/5jsY7YSJBs4

The value of Bitcoin is driven almost entirely by speculation. Speculative assets are not known for their stability.

>> No rational person would ditch traditional banking in favor of Bitcoin.

There are people who have made arrangements to receive their payroll disbursements in BTC.

While there are not many of these people and they probably all still maintain some form of traditional bank account, I am curious if you would define these folks as irrational (by your definition)?

I'll ask you... Bitcoin is a high-risk, aggressive investment by any definition. Which is fine if you believe it and like that sort of thing (other than killing the planet but that's a different question.)

Would you define someone who put 100% of their net worth into an aggressive, high-risk investment as irrational?

What about the CO2 impact of fiat currency in practice by governments & central banks? War has costs, so does welfare, and the electricity used to spin propaganda, etc. These are externalities that nobody is looking into, unless they have tinfoil hats on.

Bitcoin is a paperclip optimizer. Every time you think the amount of energy it currently consumes is justified it will continue to consume more energy in the future.

Tbf, traditional banking is more than just moving cash from one account to another. If anything, the vast majority of activity inside / within banks is dedicated to the numerous services they offer.

What’s the lifetime of a Tesla anyway? 6 years?

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