In 2000, Lawrence Berkeley Laboratories did a survey on computer equipment in the United States and California. They found that there are about 122 million displays and terminals in the United States (Kawanmoto, et. al.), of which 68 million are in commercial buildings and industrial facilities. About 15 percent are in California, which accounts for 10 million computers in non-residential use.
Thirty percent of the 10 million, or 3 million, are left on overnight without their power management capabilities enabled. Switching the displays and terminals off at the end of the day would save 85 watts (per computer) times 3 million; or 255 megawatts.
The California winter peak is in the evenings, so this analysis applies to that situation.
For summer, the challenge will be to encourage people to turn off their monitors when they leave for lunch or a meeting to conserve the 750-850 megawatts that these non-residential consumers use.
Computers should be shut off when not used for long periods of time, such as overnight. When you're away from your computer, use the "sleep" or "energy-saver" mode. This will turn off the monitor, but your computer will not have to be restarted.
Even better would be to turn off the computer, monitor and peripherals using the surge protector - control strip. Some peripherals, such as modems - especially DSL and cable modems - draw power even if the computer is not using them.
Screen savers should be not used because they consume more electricity displaying graphics and moving images. And with modern monitors there is little chance that a screen will be "burned" and because they may actually impede the power-saving mode.
When looking to buy a new computer or monitor, look for the ENERGY STAR® label. An ENERGY STAR qualified computer uses 70 percent less electricity than computers without enabled power management features.
Media & Public Communications Office
California Energy Commission
1516 Ninth Street
Sacramento, CA 95825