Computer energy efficiency
THE GIVE GRID BRANDING
Computer power usage can be cut with a few simple changes.
Benefits of computer energy efficiency
Who’s doing it?
Computers are one of the most common appliances in community sector
organisations. They are often left running all through the working day, and so
can also be big energy suckers particularly in large offices. But with a few simple
changes, you can reduce computer power usage quite significantly with minimal
disruption to computer users. Many of these hints can also be used on printers, air
conditioners and other appliances.
How to do it
Computers are using power all the time. For example, on desktop computers, the
computer monitor, the tower, speakers and other peripheral gadgets are all drawing
on power whenever they are turned on.
We always turn our computers
and other unneeded appliances
off at night. Gabrielle Bond,
Environmental Defenders Office, SA
We have 250 staff so we can
save a lot of energy by switching
off standby on computers.
Mohammed al Hamdany,
Multicultural Development
Association.
More information
Computer energy use per hour
http://michaelbluejay.com/
electricity/computers.html
Effects of setting sleep/standby mode rather than running screensavers...
1
Time to Complete
2
30 seconds
Effort Level
minimal
ACOSS is developing this project for and with the community sector,
in partnership with state and territory COSS networks and
the Australian Neighbourhood Houses and Centres Association.
www.acoss.org.au
Image © iStock.com/ACOSSpublications
3
$
Cost to Organisation
$0
4
Savings per year
$78
The GiveGrid project received funding from the Australian Department
of Industry as part of the Energy Efficiency Information Grants Program.
The views expressed herein are not necessarily the views of the
Commonwealth of Australia and the Commonwealth does not accept
responsibility for any information or advice contained herein.
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Computer energy efficiency
Tip #1: turn it off!
FACT: It takes more power to leave a computer on that it does to turn the computer off and on again. Overnight, on the
weekend or when the computer is not being used for long periods it is important to turn it off completely. This includes not
only shutting down the computer but turning off the monitor, and any other devices which are mains powered. There are
many energy saving power boards which turn off everything attached to them at once which is an easy method of doing
this.
Tip #2: Sleep mode saves a bundle!
Sleep mode can be your biggest energy saver for when it is impractical to switch your computer off entirely during the
day, when you are back and forth between activities.
To change your sleep settings:
+ In Windows 7 or Vista go to Start > Control Panel > Power Options (here’s a how-to-article http://bit.ly/1djxXVc,
an article about power-saving changes in Windows 7 http://bit.ly/1lHh1d1, and default settings in Vista http://1.usa.
gov/1aM12m6)
+ On a Mac go to System Preferences > Energy Saver
When buying new computers is it good to do the research on their efficiency. While a cheaper product may be enticing
initially, the long term running costs are also important to factor in.
Laptops use less power generally than an equivalent desktop model. The added benefit is that once the computer is
turned off so is the monitor so you don’t have to remember to turn it off!
Desktop models sometimes have the benefit of lasting longer and being able to be upgraded more easily which can allow
greater monetary savings, and increased performance while maintaining energy efficiency!
FACT: Using a screen saver does not reduce power consumption.
A screen saver is not the same as sleep mode.
It is simple to put a computer into standby mode after a specific period of inactivity. This means different things to
different computers but it is worth setting up your computer to do this after 5-10 minutes. Some systems will call it
standby, others hibernate or sleep.
Sleep and standby: In sleep and standby modes, the computer usually enters a low-power state, with blanked monitor
and motors switched off (e.g. cooling fans, hard disk / CD drives). The computer continues to use some power though (to
keep its electronic memory active).
Hibernate and shut down: In hibernate mode, the contents of the electronic memory are copied onto the hard disk drive
and the computer is then completely shut down. The difference between “hibernate” and “shut down” is that when the
computer is switched on again after hibernating, it will pick up where it left off (i.e. the same programs running and files
open). After shutdown, however, the computer will reboot and start again from scratch.
A computer will take only a few seconds to wake up from sleep mode, but will take longer (30 seconds to 3 minutes) to
start up again from hibernate or a complete shutdown. Hibernate is a good choice for overnight switch-off, while sleep
mode may be better suited to times when the computer is used intermittently during office hours.
ACOSS is developing this project for and with the community sector,
in partnership with state and territory COSS networks and
the Australian Neighbourhood Houses and Centres Association.
www.acoss.org.au
The GiveGrid project received funding from the Australian Department
of Industry as part of the Energy Efficiency Information Grants Program.
The views expressed herein are not necessarily the views of the
Commonwealth of Australia and the Commonwealth does not accept
responsibility for any information or advice contained herein.
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