What is kilowatt hour use of roof deicers?

A kilowatt hour is the use of 1000 watts of power in 1 hour. The deicers should have a rating of a voltage such as 110 volts or 220 volts and a current of "X" amps. Multiply the voltage (in volts) times the current (in amps) and you will then know how much "power" in watts the deicer uses. My guess is you will see numbers such as 120 volts at 5 amps. Therefore 120 x 5 = 600 watts per hour or .6 kilowatts per hour.