Can you explain the difference between W, kW and kWh?

Can you explain the difference between W, kW and kWh?

Kilowatt hours (kWh) show how many kWs an appliance uses each hour to run. It is simply a unit of measurement that equals the amount of energy you would use if you kept a 1,000-watt (W) appliance running for an hour.

How much would it cost to run a 1000w (1kW) heater for 1 hour if you are charged 25c/kWh by your energy retailer?


1 - Find out how much you pay per unit of electricity - In this example, we are paying 25 cents per kilowatt-hour (kWh)


2 - Find out how much input power the appliance uses in kilowatts (kW) - The input power is usually marked on the appliance, its packaging or in the instruction manual in 'watts'. Kilowatts can be calculated by dividing watts by 1000. Using our example of an 1000w heater: 1000 watts รท 1000 = 1kW


3 - Estimate hourly running cost - Multiply the input power in kW by the price of your electricity per kilowatt-hour (kWh).

1kW x 25c per kWh = 25 cents per hour

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