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Computers

Computers and other electronic equipment in a home office

Most households own at least one computer and many own multiple computers and an assortment of peripheral devices. Computers account for up to 5% of home electricity use.

Energy efficiency and computer equipment

Your computer and monitor are likely to account for the majority of the energy used by your computer equipment, with monitors representing around 25% of the energy of a computer. If you use multiple, larger monitors, this has the potential to increase your household electricity consumption.

Printers, scanners, multi-function devices (MFD), scanners, speakers and modems, routers, fax machines, answering machines and cordless phones also use energy. The combined energy use of these devices can be significant if they are left running continuously.

Choose an energy efficient computer monitor

Compare star ratings

energy rating label with additional stars for television

Energy rating

The energy rating label helps you compare the energy efficiency and running costs of different devices such as computer monitors. The star rating is shown in the red band at the top of the label and can range from 1 to 6 stars. The more stars, the more energy efficient the computer monitor will be, and the lower the running costs. Super-efficient models could have up to 10 stars, with the extra stars shown in a crown at the top of the label.

An energy rating scheme has not yet been introduced for laptops and tablets as these are available in a wide range of configurations which makes comparing their energy efficiency difficult.

Energy consumption

Compare the energy efficiency of different computer monitors, using the star rating system, then use the numbers in the energy consumption box to find out the model's annual energy consumption. Note that this figure is based on the use of the monitor for 10 hours per day, which is relevant for home office and business use. Most households will probably only use the monitor for around one to two hours per day. When purchasing a new computer monitor, use the Energy Rating Calculator to choose a model with as high a star rating as possible.

Minimum stars

When you buy a new computer monitor, pick a model with at least a 4-star rating to improve your household's energy efficiency.

Choose your computer monitor wisely

  • Size: Choose the smallest possible monitor for your needs. Larger monitors consume more electricity than smaller monitors.
  • Screen technology: Liquid Crystal Display (LCD) and Light Emitting Diode (LED) monitor technology is replacing Cathode Ray Tube (CRT) technology in virtually all but a few specialised applications. In general LCD and LED technologies are more energy efficient than CRT technology.

Energy saving power-boards

Standby power can comprise as much as 10% of your electricity bill. This is because many people use the standby mode on their devices, which means they're still using energy, even when they're not actively operating.

Regardless of the type of computer monitor you have, an energy saving power-board (SPC) can reduce the amount of energy wasted when appliances (like computers and their peripherals) are left on when you're not using them. SPCs switch off these devices when the computer is switched off or when it goes into sleep mode, saving you energy and money.

Running costs for computer monitors

The table below shows annual running costs for different sized and star-rated computer monitors.

Screen size Energy star rating Annual running cost* Annual GHG emissions (kg)** Annual running cost* Annual GHG emissions (kg)** Annual running cost* Annual GHG emissions (kg)**
    1 hour per day 3 hours per day 8 hours per day
16 inch
(41cm)
3 star rating $4.0 15 $9.1 34 $21.9 81
5 star rating $3.0 11 $6.2 23 $14.1 52
7 star rating $2.4 9 $4.3 16 $9.2 34
20 inch
(51cm)
3 star rating $4.7 17 $11.4 42 $27.9 103
5 star rating $3.5 13 $7.6 28 $18 66
7 star rating $2.7 10 $5.2 19 $11.6 43
24 inch
(61cm)
2 star rating $6.7 25 $17.4 64 $44 163
5 star rating $4.1 15 $9.4 35 $22.6 84
7 star rating $3.1 11 $6.3 23 $14.6 54
27 inch
(68cm)
2 star rating $7.6 28 $20.1 74 $51.3 190
5 star rating $4.5 17 $10.8 40 $26.4 98
7 star rating $3.3 12 $7.2 27 $17.0 63
32 inch
(81cm)
1 star rating $11.7 43 $22.0 81 $83.8 310
3 star rating $7.9 29 $14.5 54 $53.8 199
6 star rating $4.7 17 $8.0 30 $27.7 102

*Calculations assume an electricity tariff of 31.9c/kWh, based on a typical Melbourne tariff. This does not include any pay-on-time discount, which would reduce the amount paid.
** GHG = Greenhouse Gas coefficient used is 1.18 kilograms of carbon dioxide equivalent emissions per kilowatt hour.

Use your computer monitor efficiently

  • Use power management features: Use the monitor's power management features such as power down, sleep and hibernation modes.
  • Turn off your monitor: Turn off your monitor if you won't be using it for at least 20 minutes.
  • Turn off your computer: Turn off your computer when you have finished using it or if you're not using it for the next hour or so.
  • Don't use screen savers: Screen savers are not energy savers and can actually use more energy.
  • Reduce your screen brightness: Reduce brightness to the lowest setting you're comfortable with. Some models come with adaptive brightness.
  • Turn off the power strip/surge protector: If your monitor has a power strip/surge protector, turn off the switch on the power strip when the monitor is not in use, to prevent using power even when the monitor is shut off.

Dispose of your computer equipment responsibly

Ensure that when you buy a new product to replace an old one, you take the necessary steps to dispose of your old product responsibly. Recycling computer equipment will reduce landfill, conserve resources and reduce the amount of greenhouse gases created in the production of new materials.


Examples of energy and water rating labels

Energy and water ratings

Energy rating labels help you compare appliances so you can and choose the most energy and water efficient, and save money on running costs.

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Energy rating label

Energy rating calculator

The Energy Rating Calculator and app allows you to calculate the energy consumption and running costs for an appliance before you buy it.

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