The measure of a heat pump’s heating performance is called coefficient of performance or COP. It’s the ratio of useful heat output, divided by required energy input, where both the output and input are expressed in the same physical units.
The old message from some allegedly distressed person in a far-flung country asking you to wire them a sum of cash to get them out of trouble. Or the one where they found some long-lost dough that has my name written on it, but first I have to send them my bank-account information.
