Saving energy with desktops, laptops and monitors is easy and only takes a few clicks. But these simple steps make a huge difference in the energy your computer equipment uses. Below are directions for setting computer management options in several popular platforms.
Power Management features — standard in Windows and Macintosh operating systems — place monitors and computers (CPU, hard drive, etc.) into a low-power "sleep mode" after a period of inactivity. Simply touching the mouse or keyboard "wakes" the computer and monitor in seconds. Activating sleep features saves energy, money, and helps protect the environment.
To maximize power savings, the U.S. Environmental Protection Agency (EPA) recommends setting computers to enter system standby or hibernate after 30 to 60 minutes of inactivity. To save even more, set monitors to enter sleep mode after 5 to 20 minutes of inactivity. The lower the setting, the more energy you save.
In Colorado, the energy used to power the average computer monitor for one year produces as much carbon dioxide (CO2) as a car idling for 12 days. Setting your monitor to go to sleep when not used for a period can cut energy use by up to 90%. Setting your computer to go sleep as well saves even more. And turning off all your computer equipment when you’re not using it saves the most.
I have my screen saver activated. Do I need to activate power management features?
Screen savers generally do not save energy. In fact, certain graphics-intensive screen savers can cause the computer to burn twice as much energy, and may actually prevent a computer from entering sleep mode.
Do computers and monitors use more energy with power management features activated due to power surges when cycling on and off?
A popular myth holds that leaving lights, computers, and other appliances on uses less energy than turning them off and also makes them last longer. In reality, the small surge of power created when some devices are turned on is vastly smaller than the energy used by running the device when it is not needed. Source: "Eleven Energy Myths: From Efficient Halogen Lights to Cleaning Refrigerator Coils", Lawrence Berkeley National Labs.
Can sleep features wear out hardware by forcing the computer to turn on and off several times a day?
"Modern computers are designed to handle 40,000 on-off cycles before failure, and you're not likely to approach that number during the average computer's five- to seven-year life span. In fact, IBM and Hewlett Packard encourage their own employees to turn off idle computers, and some studies indicate it would require on-off cycling every five minutes to harm a hard drive." Source: Rocky Mountain Institute Home Energy Brief #7 Computers and Peripherals.
For more Frequently-asked questions about power management visit the EPA’s Energy Star website.
To turn off screen savers, go to System Preferences in the Dock. In the System Preferences window, select Desktop/Screen Saver. Select the Screen Saver window pane and move the “Start Screen Saver” slider to “Never”.
Set your computer and monitor to go to sleep when they’re idle. Go to System Preferences in the Dock. In the System Preferences window, select Energy Saver.
To schedule a shut down time, click “Schedule” in Energy Saver preferences to schedule a time for your computer to shut down to make sure it’s turned off when you’re not working.
In Displays preferences, turn down the brightness of your display.
Turn off AirPort when it’s not in use. You can turn off AirPort using the AirPort status menu, Internet Connect, or Network preferences.
To see how energy efficient your Mac is, as well find other information about Apple and their environmental impact please visit the Apple Environment website.
The Windows operating system uses “power plans” to help you save energy. A power plan is a collection of hardware and system settings that manages how your computer uses power. Power plans can help you save energy, maximize system performance, or achieve a balance between the two. Windows provides the following default plans to help you manage your computer's power:
Your computer manufacturer might provide additional power plans.
Creating a power plan on Windows 7
Creating a power plan on Windows 8
If you’re using a University computer and you are unable to change your energy settings it may be because the system administrator might have disabled or even removed certain settings by using Group Policy. If you think that Group Policy is preventing you from changing a setting that you need to access, contact your system administrator or department Computing Support Representative (CSR).
Another possibility is that you might not have the required user rights to change power settings because your system administrator has changed the permissions that are associated with these settings.