One problem with bitcoin is requiring too much energy use, but anyways it is independent from the "computer payment file" which can be used with multiple methods of payment. (Computer payment file is also intended to solve some other problems involved with computer payment, including various types of cheating that the merchant might do.)
It's an unfortunate mathematical requirement to create trust in a hostile/trustless reality. Just like how it's inefficient but necessary to spend money on defense in a world with potentially hostile foreign powers, we need to spend energy to ensure no parties can compromise the blockchain. There's no way around it (no, PoS is flawed).
It is easy to save energy when you are OK with a lower level of decentralization. I could probably run a payment processor on my computer alone that handles 100k transactions per second.
I happen to know a guy who has invested a lot in solar parks. He’s deeply unhappy about that investment because the electricity prices are often zero or negative when the sun is up and he’s underwater on that investment.
I also know a guy who recently installed a dummy load in a thermal power plant which they switch on when they can’t give the power to the network due to overcapacity, as they can’t just switch off the plant willy nilly.
The point is, in a grid with lots of renewables in it not only there’s a lot of stray energy that can be captured, but a flexible load that can be switched on/off in milliseconds is actually hugely valuable if we’re to have stable grids.
On top of that, how many people die each year due to the American War Machine that can only exist due to the US Dollar and the Fed's ability to print money and pass off the debt to the future generations?
