Trading bitcoin probably uses less electricity than trading with fiat currencies. *Creating* ("mining") bitcoin takes a fair amount of power, though I don't know how it compares to the amount of power required to make the paper/plastic or mine the metals to print or stamp the equivalent value of notes & coins. Especially considering that notes wear out and need replacing reasonably frequently (as do coins though less frequently).
Your suggestion that bitcoin is only used by criminals is as wrong as suggesting that cash is only used by drug dealers.
Biting the hand that feeds IT
