[r3ctilinear]

Incorrect. The proof of work difficulty scales automatically. If the miners/hash-power reduces then blocks become easier to mine.

The Bitcoin blockchain could subsist on a minuscule fraction of todays energy usage if the majority of miners decided to throw away their investments and stop mining.

[boublepop]

Is this a joke? Yes, bitcoin could function without using any energy at all if there where no transactions and no miners. That doesn’t change that currently independent of transaction numbers a huge amount of energy is being wasted, and the minimal waste per transaction in a theoretical maximum transactions/energy scenario would still have you spending more than our entire energy production just heating up silicon if we relied entirely on Bitcoin for financial transactions.

[uh-quan]

Energy isn't being wasted, that's the point. What proof of work and the blockchain allows is a monetary network that (a) does not rely on trusted third parties for verification, whose (b) unit of currency does not rely on states or central banks, which cannot be trusted to avoid inflation.

Whatever else you may think of those features, it's a bit weird to call it pure waste when clearly millions of people find this incredibly valuable.

[Kbelicius]

But it would not be possible for it to maintain its price and usefulness at that minuscule fraction of todays energy usage.