>A screensaver wastes power when it shows you the pretty graphics. It keeps the screen out of power-save mode and keeps the CPU and GPU active.
This is my attempt to quantify just how much power the screensaver wastes for just one average Ubuntu user. Using the default Ubuntu setup the screensaver starts after 10 minutes as a blank screen and it asks the monitor to sleep after 40 minutes. *Diff = difference between device in normal operation and power save mode in watts.
- % CRT Use: 50%
- Diff CRT: 60
- Diff LCD: 25
- Time screensaver is active a day: 2 hour
.50 * 60 + .50 * 25 = Diff Avg Monitor 42.5 Watts (also Watt hours)
Total for one user per day is 85 Watt hours.
That is 31 KwH for a year. Or at $ .15 a KwH, $5.
- User Base Of Ubuntu Desktop: 10 Million
- Diff Screensaver: 85 Watt-hours (a day)
That is 850 MWH (Million Watts) a day for all Ubuntu users.
That is 31 GWH a year. Or somewhere in the range of $46,537,500 a year.
Please if you can get more accurate variables please tell me about them, also send corrections. Kill the screensaver, Save the World.