Description of task

There is an article about how to use FreeBSD on laptops. It does not have a section on how to tune power consumption to get more battery live when running it on battery power only. There is a wiki page with some steps that describe what one can do to achieve this: http://wiki.freebsd.org/TuningPowerConsumption The goal is to update the article with the information presented in the wiki page so that the a separate chapter describes the steps on what you can do to preserve power.

Task requires:

A FreeBSD system (in a VirtualBox Virtual Machine) installed on your computer. 
Knowledge of the documentation guidelines for the FreeBSD project: http://www.freebsd.org/doc/en_US.ISO8859-1/books/fdp-primer/ 
Check out a copy of the documentation tree from the documentation repository to get the source code for the chapter