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by TheSmiddy 1688 days ago
Ok cool. Let's double the energy used by banks then, still 100x as efficient as Bitcoin.
1 comments

That's a fair statement. I'm not really even sure what the $404 trillion is after trying to look up where you were going with that (all assets globally).

We should do an attempt with just US dollars. It looks like there is about $40 trillion in actual physical/digital circulation (i.e. not investments in things like crypto, buildings, stocks).

Driving even an electric vehicle uses ~250-300 Wh per mile (we can round down to 250Wh).

Bank of America, Chase, Wells Fargo, and Citigroup have about 738k (we can round down to 700k) employees and the average US commute is 32 miles (we can round down to 25). We'll assume ~235 days of work a year.

25 * 0.250 * 700000 * 235 = 1,028.1 TWh to commute for bank employees of the top four US banks per year

Which is about 25.7 Wh / $. We can safely assume this is significantly lower than reality already since we only counted the top four US banks and rounded all of our figures down. This also doesn't count any other industry required to keep USD working (like datacenters, as referenced in the paper you linked).

Edit: I'm not trying to prove you wrong or anything, I'm just genuinely curious if this "bitcoin is worse" statement is correct.

Thanks for working this one out, unfortunately you're off by a factor of 1000.

Your calculation comes out to 1.028 TWh

1 TWh = 1,000,000,000 KWh

Yep, my bad! So commutes aren't as significant a contributor as I thought. I ran through some more calculations trying to only use the US, and it looks like the Wh / $ is somewhere around 3.51. Is there any other category of use that isn't being included? This is a pretty stark difference, even being many times more than the first calculation.

Commute: 1.028 TWh

Data centers: ~3.3TWh per trillion (for USD) = 132 TWh

ATMs: 470,135 independent in the US (1.27MWh each per year) = 0.597TWh

Banks: ~98,000 in the US (PDF wasn't clear, using 60MWh each per year) = 5.88 TWh

Card networks: ~1TWh/yr (just assuming "half" of global)

Total: 140.5TWh/yr

https://data.worldbank.org/indicator/FB.CBK.BRCH.P5?location...

https://blog.sfgate.com/lifestyle/2020/08/31/its-electric-ho....

OK the main discrepancy is from the Data center calculation. The Galaxy PDF lists the top 100 banks as owning $70Tn of deposits. I calculated using the galaxy energy number but divided by total deposits wheras I should have only used the data for the top 100 banks as they did.

I think your calculation of 3.5 Wh/$ is closer to the real number. When I put $70Tn instead of $404Tn in I get 3.71Wh/$