Mining

The Bitcoin network now uses 0.15% of global energy. And while environmental costs are growing, the dream of a payment system protecting everyone's freedoms is fading in favour of yet another capitalistic house of cards. No matter if it falls, this is a social construct that escalated quickly and now has real costs.

Had bitcoin been mined by doing something useful, then there would be a correspondence between useful work and the number of bitcoins you get … That creates a mental anchor point in people’s mind for how much a bitcoin should cost.

—Emin Gün Sirer in Adam Rogers: The Hard Math Behind Bitcoin's Global Warming Problem