Kilowatt (or kW) is 1,000 watts, which is a just a measure of power. That’s as much as you really need to know about kW. A kilowatt hour (or kWh) on the other hand, is a unit of measurement that equals the amount of energy you would use if you kept a 1,000-watt appliance running for an hour.

As an example, a dishwasher has a wattage rating of between 1.2kW and 2.4kW (generally stated in watts when written on the back of the machine, like 1200-2400W). So, if you use your dishwasher for one hour, it will consume between 1.2 to 2.4kWh. Multiply this by the cents per kWh in your bill, and you can solve the cost of running the dishwasher for this hour. If your general usage rate is 25¢, it would cost between 30 and 60 cents per hour to run the dishwasher.


It’s important to understand what electricity tariff you areon as the general usage rate can vary significantly if you are on a time of usetariff, from less than 20 cents/kWh to more than 40 cents/kWh. So, it’s good tothink before your switch that dishwasher on.

While it’s hard to be precise because the similar appliances can have very different wattages, here are some rough examples of what 1 kWh can power and roughly how much it might cost:

Appliance

Watts

Cost p/h (¢)

400L refrigerator 68 1.4
Pool pump 1100 22.0
Toaster 1000 20.0
Underfloor heating - bathroom 900 18.0
Washing machine 900 18.0
Vacuum cleaner 1200 24.0
Mobile phone charger 5 0.1
Electric oven 2100 42.0

*The average price of electricity paid by individual customers varies depending on their location, retail contract, usage and tariff structure. Electric appliance running costs are calculated using a rate of25c/kWh. Source: Ausgrid

While the costs above may seem like it is a small cost per day, when you tally up all the appliances in your home, it can really add up! It is important to be conscious of these values for your next big appliance spend. You might be saving a bit of money up front buying a cheaper dishwasher, but if it has terrible efficiency you might end up paying over and above your initial savings.

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