I just installed Linux on a laptop of mine (it's Lubuntu 15.04 on a Lenovo X201, Core i5 M540, 2GB mem). I'm currently seeing 21580 mW power draw with a couple of apps open (Firefox with a few tabs and Ghostery, and LibreOffice Writer). I haven't tweaked the system in any way, and am using the stock kernel; this means ~3h or so of battery life with my model and my current battery.
What should I / can I do to reduce the power draw? I'd rather get generally-useful advice rather than something specific to the distro or apps I'm using just now (but distro-specific advice is also relevant).
- I am willing to turn off some hardware functionality, as long as it's very easy for me to turn it back on when I need to.