February's Green Tip

Sleep-deprived? It’s possible that your computer is! Look around your classroom, office or lab and notice how many computers are left on when they’re not in use. Place monitors and computers into a low-power "sleep mode" after a period of inactivity. Simply touching the mouse or keyboard "wakes" the computer and monitor in seconds. Set monitors to enter sleep mode after 5 to 20 minutes of inactivity. The lower the setting, the more energy you save.*

*ENERGY STAR

Myth Busting

Turning a computer on and off is bad for the computer. 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 life span.* Furthermore, you don't save energy by using a screen saver when your computer’s not in use; 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. **

* Rocky Mountain Institute
** ENERGY STAR

Your Actions Add Up!

If every student, faculty, and staff ran their computer 24/7 for a year without sleep mode or powering off, it would result in 16.3 MILLION pounds of greenhouse gas emissions! Turning those computers off or into a low power standby state for 1/2 of that time could save up to $1.3 MILLION in utility bills and 8.2 MILLION pounds of CO2. That's like taking 700 passenger vehicles off the road!

*Harvard Fact Book, 2007 Harvard Greenhouse Gas Inventory, Harvard UOS Engineering & Utilities FY10 Utilities Rate Forecasts, Harvard DCE Computer Energy Use

Resources

• Want to learn how to set power management on your computer? Download our power management fact sheets for Windows and Mac. They contain instructions for both manual and automatic management.
• Buy energy efficient computers. Look for the EPEAT or ENERGY STAR logos in Harvard’s University Information Systems’ (UIS) catalogs.
• Get Green Tip posters and past Green Tips from our website: http://green.harvard.edu/greentip