How can I optimize Ubuntu for minimal energy usage?

Solution 1:

you can use a tool named as pm-powersave. It will turn your Ubuntu into low power mode.

usage:

• pm-powersave true will start power save mode.

• pm-powersave false will stop the power save mode.

Fore more information

manpage for the http://manpages.ubuntu.com/manpages/saucy/man8/pm-powersave.8.html command

Solution 2:

One of the biggest uses of power is the hard drive. If you're just using the computer for it's word processing capabilities, you might be able to go for significant periods of time without reading or writing to the hard disk.

1. Disable filesystem journaling. This is one of the most frequent uses of the hard drive. It will also allow the next item to be much more effective.
2. Use buffered disk writes. It's possible to buffer disk writes for a significant period of time before writing them to the hard disk. If you're only running one program, this could potentially allow your hard disk to remove off for 20 or 30 minutes even if you're writing to the device. I use laptop-mode-tools. I don't know the ubuntu approved method for this.
3. Other hard disk power saving options. (Spindown more often, etc.)
4. As mentioned previously, use powertop to find other configuration changes that can be made to reduce power consumption.
5. Undervolt your CPU. This one is quite a bit more involved than the others. https://wiki.ubuntu.com/UndervoltingHowto