Knowing how much your appliances cost to run can help you to keep control of your energy use and bills.
Use running costs to help you choose when buying a new appliance. Some appliances such as portable heaters may have a low purchase price, but could cost you a lot more to run over the life of the appliance than a more efficient model.
On this page:
How to calculate running costs yourself
Average energy use of home appliances:
Heaters and cooling appliances
Fridges and freezers
Clothes washing and drying
Lighting
Other household appliances
Stand-by power consumption
Achieving the minimum running cost
How to calculate running costs yourself
Follow the steps in the tables below to calculate the running costs of electric or gas appliances.
Calculating electrical appliance running costs
| 1 | Find out the appliance's input power in watts or kilowatts
| Label shows 2400W |
| 2 | If neccessary convert input power to kilowatts (kW) or megajoules (MJ)
| Divide 2400W by 1,000 = 2.4kW
|
| 3 | Check your bill for your energy tariff rate - the amount you pay per unit of electricity
| If you are unsure you can use 30 cents per kWh for electricity |
| 4 | Multiply the input power by the energy tariff to get the hourly running cost
| 2.4 x 30 = 72 cents per hour |
| 5 | Multiply the hourly running cost by the number of hours per day you run the appliance to get a daily running cost
|
Calculating gas appliance running costs
| 1 | Find out the appliance's input power in joules or megajoules
| Label shows 4MJ |
| 2 | If neccessary convert input power to kilowatts (kW) or megajoules (MJ)
| Convert joules to megajoules (MJ) by dividing by 1,000,000. In this case no conversion required
|
| 3 | Check your bill for your energy tariff rate - the amount you pay per unit of gas
| If you are unsure you can use 2 cents per MJ for gas |
| 4 | Multiply the input power by the energy tariff to get the hourly running cost
| 40 x 2 = 80 cents per hour |
| 5 | Multiply the hourly running cost by the number of hours per day you run the appliance to get a daily running cost
| If the appliance is turned on 5 hours per day:
5 x 80 cents = 400 cents a day
divide by 100 to get the amount in dollars - 400/100 = $4
|
Not all appliances operate constantly at full power. Appliances with high and low settings or thermostats can use less energy.
The most accurate way of finding out an appliance's running cost is to use an appliance power meter. You can borrow a power meter in the home energy toolkit free of charge from most public libraries.
Note that these costs do not take into account the electricity or gas supply charge which also form part of your energy bill.
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Average energy use of household appliances
The following running costs are based on:
- an average peak electricity tariff of 30 cents per kilowatt-hour (1000 watts equals a kilowatt) and an off-peak electricity tariff of 13 cents per kilowatt-hour.
- an average gas tariff of two cents per megajoule.
Heaters and cooling appliances
Fridges and freezers
Clothes washing and drying
Lighting
Other household appliances
Stand-by power consumption
How these figures have been calculated
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Heating and cooling appliances
| Portable radiant heater | 1 kWh - 2.4 kWh | $0.30 - $0.72 |
| Portable convection heater | 1.6 kWh - 2.4 kWh | $0.48 - $0.72 |
| Gas space heater - small | 13 MJ - 25 MJ | $0.31 - $0.60 |
| Gas space heater - large | 26 MJ - 40 MJ | $0.62 - $0.96 |
| Fans | 0.1 kWh - 0.2 kWh | $0.03 - $0.06 |
| Electric blankets - high setting | 0.07 kWh | $0.021 |
| Electric blankets - low setting | 0.017 kWh | $0.005 |
The most energy efficient way to use electric blankets is to preheat on a high setting then switch to a low setting for the rest of the time.
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Reverse cycle air conditioners
The energy use and running costs are based on the reverse cycle air conditioner operating for:
- 250 hours a year for heating
- 200 hours a year for cooling.
| Reverse cycle (2-3 kW output) | 87 kWh - 109 kWh | $26.10 - $32.70 |
| Reverse cycle (5-6 kW output) | 141 kWh - 237 kWh | $42.30 - $71.10 |
| Reverse cycle (7-20 kW output) | 212 kWh - 700 kWh | $63.60 - $210.00 |
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Fridges and freezers
| Fridge/freezer (200-300 litres) | 85 kWh - 134 kWh | $25.50 - $40.20 |
| Fridge/freezer (300-400 litres) | 82 kWh - 143 kWh | $24.60 - $42.90 |
| Fridge/freezer (400-500 litres) | 87 kWh - 151 kWh | $26.10 - $45.30 |
| Fridge/freezer (500-600 litres) | 100 kWh - 187 kWh | $30.00 - $56.10 |
| Chest freezer (100-200 litres) | 44 kWh - 80 kWh | $13.20 - $24.00 |
| Chest freezer (200-300 litres) | 68 kWh - 100 kWh | $20.40 - $30.00 |
| Chest freezer (300-400 litres) | 64 kWh - 110 kWh | $19.20 - $33.00 |
| Chest freezer (400-500 litres) | 86 kWh - 132 kWh | $25.80 - $39.60 |
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Clothes washing and drying
The energy use and running costs for clothes washers is based on one cycle a day and warm wash cycles having a minimum temperature of 35°C.
The clothes dryer energy use and running cost is based on one cycle per week.
| Top loader (cold wash) | 11 kWh - 33 kWh | $3.30 - $9.90 |
| Top loader (warm wash) | 71 kWh - 300 kWh | $21.30 - $90.00 |
| Front loader (cold wash) | 18 kWh - 39 kWh | $5.40 - $11.70 |
| Front loader (warm wash) | 38 kWh - 148 kWh | $11.40 - $44.40 |
| Clothes dryer | 21 kWh - 112 kWh | $6.30 - $33.60 |
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Lighting
| 10 W light globe | 0.01 kWh | $0.003 |
| 20 W light globe | 0.02 kWh | $0.006 |
| 35 W light globe | 0.035 kWh | $0.01 |
| 50 W light globe | 0.05 kWh | $0.015 |
| 100 W light globe | 0.1 kWh | $0.03 |
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Other household appliances
Televisions
Dishwasher
Household appliances
Televisions
The energy use and running costs for televisions is based on ten hours of viewing per day.
| Plasma (90cm - 110 cm) | 102 kWh - 265 kWh | $30.60 - $79.50 |
| Plasma (130cm - 165cm) | 163 kWh - 447 kWh | $48.90 - $134.10 |
| LCD (50cm - 90cm) | 25 kWh - 131 kWh | $7.50 - $39.30 |
| LCD (90cm - 183cm) | 78 kWh - 320 kWh | $23.40 - $96.00 |
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Dishwasher
The energy use and running cost for the dishwasher is based on the appliance operating for one cycle every day.
| Dishwasher | 32 kWh - 142 kWh | $9.60 - $42.60 |
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Household appliances
| DVD player | 0.02 kWh - 0.1 kWh | $0.06 - $0.30 |
| Home theatre | 0.3 kWh - 1.4 kWh | $0.09 - $0.42 |
| Stereo | 0.06 kWh - 0.4 kWh | $0.02 - $0.12 |
| Games console | 0.03 kWh - 0.165 kWh | $0.01 - $0.05 |
| Microwave oven | 1.3 kWh | $0.39 |
| Kettle | 2.4 kWh | $0.72 |
| Slow cooker | 0.15 kWh | $0.05 |
| Computers | 0.3 kWh - 0.5 kWh | $0.09 - $0.15 |
| Cordless telephones | 0.01 kWh | $0.003 |
| Oxygen concentrator | 0.28 kWh - 0.48 kWh | $0.08 - $0.14 |
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Stand-by power consumption
The amount of energy used during stand-by could be up to 20 watts, depending on the type and model of appliance. Every one watt of stand-by will add approximately $2.63 to your annual energy bill if left on all the time.
The following table shows the average stand-by energy use for common household appliances.
| Cordless phone | 3 W | $7.89 |
| Television | 10 W | $26.30 |
| DVD player | 8 W | $21.04 |
| Computer monitor | 5 W | $13.15 |
The cost of stand-by for these five appliances alone is $68.38 per year. If you consider how many appliances you have on stand-by in your home, you can see how the cost can start to add up.
Check the manufacturer's information for stand-by power information. If a stand-by wattage is provided you can calculate the running costs.
An appliance meter, such as the one available for loan in the home energy toolkit, can determine exactly how much electricity an appliance is using in all power modes. See Stand-by power for more information.
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Achieving the minimum running cost
The minimum running cost can be achieved by a combination of:
- selecting an appliance that suits your needs and has the lowest input watts or megajoules - use the energy rating label for larger appliances
- operating the appliance for the shortest amount of time possible
- using thermostat controls or energy saving features - eg low energy use settings
- choosing the lowest appropriate energy tariff - compare electricity and gas prices and plans.
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