Adjust computer power settings to save energy
Powering computers requires a substantial amount of energy, yet most computers are in use only a fraction of the time they're on. Adjusting your computer’s power settings to save energy means the computer and monitor will switch into sleep mode when idle.
How to adjust your computer's power settings
Contrary to the myths that would have you believe it takes more energy to start your computer than leaving it on all night, computers require only a small surge of energy when they're turned on.
Here are some general guidelines for when to shut it down.
- If it will sit idle for > 20 minutes, turn off just the monitor (if its a desktop)
- If it will sit idle for more than 2 hours
Another button to adjust on the power management panel is the screen's brightness. Dimming this will also decrease power demand.
The ENERGY STAR power management pages give instructions on how to enable these features for your specific computer type and operating system. Here's another helpful guide to setting your computer's power features.
Just remember: even brand new, ENERGY STAR computers may not come with their power management settings adjusted to save you the most energy possible. Verifying your machine's settings as soon as you pull the computer out of the box.
Reducing your computer's energy use helps you go green because...
- It reduces its demand for energy, preventing the release of greenhouse gases into the atmosphere.
Of the total electricity used by computers, only 35 percent is used for actual computing. The remaining 65 percent is wasted while computers run idle. Whether in use or not, computers consume about the same amount of energy. Contrary to conventional wisdom, screen savers do not save energy, and actually consume 40 to 100 watts, even though the monitor appears to be inactive. What's more, they can even prevent a computer from going into a sleep mode.
The average American is responsible for almost 22 tons of carbon dioxide emissions per year, the largest source being electricity generation, representing approximately 30 percent of emissions. Home office equipment and electronics account for about 20 percent of this electricity use as most computers are left on for 24 hours a day. To power a conventional computer all day costs between $115 - $160 in electricity per year, releasing 1,500 pounds of carbon dioxide into the air. Given that a tree absorbs between 3 to 15 pounds of carbon dioxide annually, it would take between 100 and 500 trees to offset these emissions for just a year.