Virtual governors

Virtual governors are an abstraction of the CPU governors and their parameters. Since a significant part of the energy saving is done by the parameters of the CPU governors switching only the CPU governors of a profile does (most of the time) not make much sense. The most important parameters are the thresholds of the ondemand and conservative governors, they are given in percent of the system load and tell the governor when to increase the frequency (up threshold) or decrease the frequency (down threshold).
For more information on the parameters of the CPU governors see the detailed information of the respective governor.
If the userlevel power user is chosen, there is the additional possibility to run a shell script (or a shell command) after the switching of the governor. The commands entered there will parsed by a shell and executed as root. Which virtual governors do I need to save battery?