Since using GNU/Linux as my main operating system in my Laptop (HP Pavilion DV5000). If you want to see the review, you can visit this link. I figured that my laptop’s battery is discharging faster than when I use in Windows. So I search for “battery improvement in linux” through Google. Later that I found, the correct keyword is “Better Power Management in Linux” or “Improve Battery Life in Linux” 
From Google, I found link to Lesswatts.org, a website from Intel where they provide some tips and tools to saving powers on Intel systems with Linux. They adviced me to install powertop, a program that can inspect which program that eat most power from my Laptop. I also found some useful howto from Ubuntu Forum thread. For HP Pavilion owner, maybe this blog post and this can help you to improve your battery life.
Now, I feel that my linux box save some power and can stand a lot longer than before when the power went out.
Hope this post can help you too.
