Saving electricity

A typical desktop computer uses about 65 to 250 watts. To find the figure for your particular computer you can contact the manufacturer (not me), or see my section on measuring electrical use.

With most devices you can look at the label to see how much energy they use, but that doesn't work so well with computers because the label gives the theoretical maximum, not the typical amount used. A computer whose label or power supply says 300 watts might only use about 70 watts when it's actually running, and only 100 even in peak times with serious number-crunching and all the drives spinning.

As long as your computer goes into sleep/standby when you're not using it, your computer doesn't use squat for electricity, compared to the rest of your household. You'll save a lot more energy by addressing your heating, cooling, and lighting use rather than obsessing over your computer. For most people, their computers' energy use is not a significant portion of their total use, even if they use their computers a lot. Of course, you should absolutely make sure your computer is set to sleep automatically when you're not using it, because it's silly to waste energy, but your computer likely isn't even close to being the biggest energy-waster in your home.

 

How much it costs to run your computer

To calculate your costs use this formula:

Watts  x  Hours Used	x  Cost per kilowatt-hour = Total Cost
1000

For example, let's say you have a big high-end computer with a gaming-level graphics card and an old CRT monitor, and you leave them on 24/7. That's about 330 watts x 24 hours x 365 days/yr = 2,890,800 watt-hours, or 2891 kilowatt-hours. If you're paying $0.14 per kWh, you're paying $405 a year to run your computer.

      recommendations

• Set the Power settings on your computer to automatically go into Sleep/Standby mode after 15 minutes or so of inactivity. If you do nothing else, do this.
• If you use a desktop, use an LCD monitor. They use lots less energy than CRT's.
• Turn your computer off when you're done for the day.
• Use a laptop computer. They use lots less energy than desktops.
• Use a Mac. Macs use way less energy than most Dells.
• Use a power strip so you can easily turn off all your computer accessories at once. BITS makes a special power strip that goes one step further, automatically cutting power to peripherals when you turn your computer off.