no one bothers using the asics of 2016 anymore which cambridge still uses in its GUESTIMATES of 121 last year
cambridge still use the s19 range and include many that are inefficient and unprofitable.. which everyone knows people retire those.
no one uses unprofitable hardware. they secondary market sell old hardware for altcoins to use whilst upgrading to latest generation asics to stay profitable
heck.. cambridge still uses a 30 j/thash rate.. although current gen asics (s19-s21) are 21-17 respectively
using current generation(bitmain s21) asics of 3.5kw for 200thash
with network peaking at 540Exahash (emphasis peak=most)
if the network was 540exahash all year
540000000 /200thash = 2700000 asics
2700000 * 3.5kw = 9450000kw/h = 9450mw/h = 9.45gw/h
9.45gw/h = 226.8gw/day = 82,782gw/year = 82.78Tw/y
82 is better then 121
now with that all said..
the 540 was a peak but assumed all year
the actual average hashrate of the year is 374767942.7 (375exa) which is a 57.48tw/year using current gen(s21) asics
the actual average hashrate of the year is 374767942.7 (375exa) which is a 71tw/year using last gen(s19) asics
US uses over 4000TW/year for all electric(residential, business, industry) which would be 80TW/year at 2% rate
but this 2% of american rate (80tw/y) is more then WORLD bitcoin usage.
the amount of bitcoin usage of electric for just american miners is far less than 2%
in short bitcoin does not use 2% of americas electric