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Computer Energy Saving Tips

a few myths about computers and energy

Myth # 1: Computers don't use much energy.
  • Office electronics are the fastest growing use of electricity in commercial buildings in the United States. Computers, as a group, use the most energy of all office equipment. The City’s 1,200+ computers use an estimated 800,000 kilowatt-hours of electricity each year--the equivalent of about 100 typical households (assuming only 10% are left on each night). In addition to their direct energy use, computers generate significant heat which adds to the buildings' air-conditioning load over much of the year.

Myth # 2: Operations costs for computers are minimal.
  • Electric power for the City’s computers cost about $46,000, or $38 per year for each computer. If all computers were turned off each night and weekend, the City would save about 20% of that cost. Put another way, we would save the energy equivalent to that used by 20 typical households.

Myth # 3: If you shut your hard drive off, it doesn't matter if the monitor is left on.
  • In fact, most monitors consume about two-thirds of a computer's total energy use.

Myth # 4: Screen savers save energy.
  • Screen savers are meant to save the monitor pixels from burn-out, not save energy. In fact, screen savers use considerably more energy than a blank screen.

Myth # 5: It is better to leave hard drives running because shutting them down puts added stress on the machine.
  • Contrary to popular belief, leaving computers on is not good for the equipment. In fact, turning it off overnight and on weekends can actually extend the life of your equipment.

Myth # 6: It takes a long time boot up every morning.
  • Although it may seem like a long time to wait when you are staring at the screen, it only takes 1-2 minutes for your computer to boot up. Please use this time to check your voice mail or conduct other tasks.

Tips to Save Computer Energy Use

Shut the computer off at night. Please turn the whole system off each night. If you can't turn off the CPU, you can always save energy by just turning off the monitor.

Turn off the monitor when you will be gone. You can save as much as two-thirds of a computer's energy use just by turning off the monitor. This does not affect your operations, just switch it back on when you return. We suggest you do this before lunch, before long meetings and any time you expect to be away from your desk for more than a half-hour. 

Set your monitor to go "blank". Since screen savers actually force the computer to use energy to run them, you can save energy by setting the monitor to blank out after a specified period. Pull down the "Screen Savers" list and choose "Blank Screen." Set the "Wait" time for the period you choose.

Don't forget about the printers. Printers also use a significant amount of energy: particularly laser printers. Please shut them off nights and weekends along with your computer.