Fiat money is trusted in good part because there are backed by institutions, mainly governments in turn are backed by armies (real soldiers and policemen). All

Fiat money is trusted in good part because there are backed by institutions, mainly governments in turn are backed by armies (real soldiers and policemen). All this uses a fair amount of energy, and there is no other way. "Cryptos" are in their infancy and there are already ways for them to dissipate less energy.