###### Asked in Home ElectricityHome AppliancesModel Trains

# You purchased a electric heating stove and you are trying to figure the amount of electric it would use It is 750 watts or 1500 watts 120V 60 Hz?

## Answer

###### Wiki User

###### December 18, 2007 1:45PM

Watts are a unit of power, so you know how much power the unit will draw when it is "on." More details on that later. First, you are billed for electricity in kilowatt-hours (KWH). (Look at your latest bill to see how much you are charged per KWH. It probably varies: so much for the first so many KWH, then a different rate for each KWH over the first threshold.) Next, a kilowatt-hour is 1,000 watts times one hour. To run the 1500 watt heater for eight hours (assuming full on, but more details on that later) would consume 1,500 times 8 divided by 1,000 = 12 KWH. Compare that to your electric bill to estimate how much it would cost. Finally, if the heater has a thermostat, it will not be "on" all the time. When the temperature around the unit rises above its thermostat setting, the heating elements will turn off, so it will no longer consume its rated power. While in this mode, main switch on but heating elements turned off by the thermostat, it wil draw some power, but only on the order of miliwatts (thousandths of a watt). It is not possible to predict its "duty cycle," how much time it will be "on" as a fraction of whole time, without either a) some impossibly complicated engineering formula and equally impossible to get figures regarding the size of the space it is heating, how drafty it is, how well insulated it is, and the ambient temperature outside the space; or b) try it out and time how long it is on and how long it is off over the course of a couple of hours. Anyway, the power rating in watts times the length of time you expect to turn it on per month divided by 1000 will give you a maximum figure for how many KWH it could possibly use. Actual consumption will be somewhat less, but impossible to predict.