According to Energy Star, turning off 1,000 computer monitors will save 200,000 kWh per year. Setting your computer to sleep mode reduces energy consumption by at least 87%. To further reduce your computer’s energy consumption, turn it off when not in use; enable the Power Management feature; and don’t use a screen saver.
EPA recommends setting computers to enter system standby or hibernate after 30 to 60 minutes of inactivity. You can save up to $75 or more per computer by activating system standby or hibernate features. To save even more, set monitors to enter sleep mode after 5 minutes of inactivity; the lower the setting, the more energy is saved.
If you’re in the market for a new computer, consider a laptop, which consumes about 75% less energy, and look for Energy Star 5 and EPEAT gold ratings.