Power Savings and Performance Modes on Ubuntu System
You could install Jupiter (http://www.jupiterapplet.org/)
Which adds this this features to your system and allow you to control it using an indicator
Just add the PPA ppa:webupd8team/jupiter to your system using this command
sudo add-apt-repository ppa:webupd8team/jupiter
Update your reposites and install it using these command(s)
sudo apt-get update && sudo apt-get install jupiter
and you are good to go
From a Terminal you can do:
sudo pm-powersave false
to run in high-performance mode.
And to run in powersave mode:
sudo pm-powersave true
Documentation: PowerManagement/ReducedPower
Full disclosure: I feel this really should set the CPU governors, but I'm not actually sure it does that! It might have been a bug on my system that has given me doubt, so it might work just fine for you. I'd welcome feedback from others on this.
Energy save mode in Windows is mostly CPU limiting. You can do that with
sudo cpufreq-set -u 0.8Ghz
or whatever the desired value is. Check minimum and maximum frequency available with
cpufreq-info |grep limits
I do that regularly when using a Laptop on battery.
Display brightness adjustments etc. are up to you.