What does power x time mean?

Answer 1

Power = energy / time

Energy = power x time

If you operate an electrical appliance for a while, then the amount of energy it used is

(power it uses when it's turned on) times (length of time it's turned on).

(power) x (time) is the amount of energy used. That's what you're billed for,

and what you pay your local utility.

Turn on a 1-KW appliance, and run it for 1 hour, it uses 1 kilowatt-hour of energy,

and that's what you'll pay for.