It is bad for the computer to turn it off and on frequently.
Computers are currently designed with the ability to power cycle on/off around 40,000 times. This is many more times that the average user will ever do in the 5-7 year lifespan of a computer. Turning off the computer also helps reduce heat, stress, and wear on the system.
Turning your computer off uses more energy than leaving it on.
The power used by a CPU to boot up is much less than the energy used by it to remain on for 3 minutes.
Screen savers save energy.
Screen savers were originally designed to protect the lifespan of monochrome monitors, which are now obsolete. Most screen savers do not save energy unless they actually turn off the screen or, in the case of laptops, turn off the backlight.
Network connections are lost when a CPU goes into low-power/sleep mode.
Newer computers will allow sleep on networks to prevent loss of data or connection.
Tips and Tricks to Green Computing
- Power off your monitor when not in use instead of using screensavers
- Enable the standby/sleep mode and power management settings
- Power computers down on weekends and evenings
- Turn off all devices until you are ready to use them (scanners, speakers, printers)
- Don’t power your computer on until you are ready to use it
- Select dark backgrounds for your screen display. Do not use bright displays, which consume more power
- Review documents and emails onscreen instead of printing them out
- Use double sided printing functions
- A computer left running continuously will emit 2,161 pounds of CO2 per year, which is equivalent to the CO2 emitted by burning 191 gallons of gasoline
- Turning a computer off at night so it runs only 8 hrs a day reduces 810 kWh per year, or a nearly 67% yearly savings.
- By turning off computers at night and weekends Lincoln City Libraries could see a savings of 55.6% in energy consumption. This means a reduction of 196 tons of C02 emitted, which is equivalent to the C02 emitted by burning 21,111 gallons of gasoline .
Create a “Green” Machine:
Enable Power Management Features:
Lincoln City Libraries encourages all computer users to turn on their Power Management Features.
- Select Start> Settings> Control Panel> and Display.
- Select the Screen Saver tab. Choose a predominantly black screen saver and set it to wait for 5 minutes
- Click on Settings or Power to reach the power management settings
- Click the Shut Off Monitor box and set for 10 minutes
- Click Ok or Apply.
- Set Turn off hard disks for 15 minutes (or less)
- Set System standby for 30 minutes (or less)
- Click Ok or Apply.
Mac OS X
- Click on the apple symbol (Apple Menu) in the upper left of your screen
- Go to "System Preferences," Click "Show All" and select "Energy Saver" from the "Hardware" row
- Click on the "Show Details" button> Select "Power Adapter" under "Settings For:" If you are unable to complete this step an administrator has prevented you from changing these settings. Please stop here
- Set "Put the computer to sleep when it is inactive" to 30 minutes (or less) using the slider
- Check the box for "Use separate time to put the display to sleep" and set the time to 15 minutes (or less) using the slider
- Check the box for "Put the hard disk to sleep when possible."
Additional Energy Saving Resources: *
Climate Savers Computing- http://www.climatesaverscomputing.org/learn/power-management-instructions/windows-2000-/-xp
Department of Energy- http://www.doe.gov
Energy Star- http://www.energystar.gov
Environmental Protection Agency- http://www.epa.gov
Green Power Equivalency Calculator http://www.epa.gov/greenpower/pubs/calculator.htm
Ohio University Green Computing http://www.facilities.ohiou.edu/greenpc/green_computing_guide.pdf
* Lincoln City Libraries acknowledges that text and concepts in this document were adapted from energy saving information contained within the listed web sites.