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kWh explained

kW and kWh explained: what does it all mean?

24 Apr 2019
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amaysim's content guy

Ah, kW and kWh....wait what?

To be fair...unless you work in the energy industry, chances are these terms will leave you scratching your head. (And yes, the correct way of writing these out is with a lowercase k and an uppercase W)

If you’re wondering what these terms mean in relation to your energy bill mean, you’ve come to the right place.


What is a kW?

kW is short for kilowatt.

A kW measures power.

Power = the combination of all the watts used to power your house.

Your appliances should tell you how many watts they require to run. One watt = one joule of energy per second.

Kilo = one thousand
Watt = a measure of power
One kW = 1,000 Watts

Ever had to change a lightbulb in your lifetime ? Chances are you might be somewhat familiar with wattage. In fact, you probably fitted a 40-watt lightbulb in your kitchen after the last one blew.

Well, a kW is just an easy way to measure electrical power over 999 watts. So your 20,000-watt generator could also be called a 20kW generator.

OK, we get it. A kW is 1,000 watts. But what does that mean for my energy bill? Well kW are used to determine the rate of electricity used at any given time, or your demand. If you’re using high-kilowatt appliances, the rate of energy needed to run them goes up.

You generally don’t pay for the demand you put on the system (kW), but how much energy you use (kWh). So when you’re comparing energy retailers, you should be looking at the electricity usage costs per kWh ($/kWh).

curious about how much electricity your appliances use? let's break it down

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What is a kWh?

A kWh measures energy.

Energy = the power (or watts) you’re using, multiplied by the amount of time those appliances are used for.

Kilo = one thousand
Watt = a measure of power
Hour = a measure of time
One kWh = 1,000 watts (or 1kW) sustained over 1 hour.

If your vacuum cleaner uses power at a rate of 1kW for one hour, you’ll have used 1kWh. Unless you’re on a ‘demand tariff’, your energy bill will show electricity usage costs per kWh.

This $/kWh change from provider to provider , and there are a other factors that can affect your costs, including peak and off-peak tariffs, as well as the state you live in, so it pays to look into the rate breakdown of your plan if you're on the hunt for a new energy plan.

From the kitchen to the laundry, our kWh appliance guide provides a rundown of your appliance use, so you can become more informed about how much electricity is being used by your household favourites