I hear you Anuj, and you’re not the first to make these points, but you don’t really reassure me. If the entire proof of work system switched to solar power tomorrow it would be using an enormous % of all world solar and would drive lots of other power use back to fossil. It’s the quantum really, not the source of power (and, having said that, as far as I can tell, mining is literally the least ethical, least green industry on earth, so the likelihood that miners will switch to renewables any time soon is tiny).

Your comparison with the power use of the fiat system is also an old chestnut and also entirely bogus. The entire fiat system (including all of banking, financial services, transactions etc. etc.) does indeed use a much larger quantum of power but it also support TRILLIONS of daily transactions, HUNDREDS OF MILLIONS of jobs, most businesses, all of the central banks and governments — pretty much everything, in fact, while Bitcoin pushes a few million transactions per day (am I right?), hardly any jobs and a vanishingly small part of global economy/culture etc. Literally no comparison.

TBH, I don’t really understand your third point. It seems obvious that sometimes technology is put to bad uses. My point here is that this particular technology, because of its dependence on proof-of-work, is bad bad bad. Unarguably bad. Unreformably bad. Just bad.