Is your laptop keyboard backlit? If you answered in the affirmative, then you have found another factor contributing more or less significantly to poor battery life. For heaven’s sake, this is certainly a very useful feature (especially when you find yourself writing on the keyboard in poorly lit environments) and valuable, but the fact remains that turning off the keyboard backlight (or at least lowering it) is an operation necessary to increase the autonomy of your laptop a little.
On many models of Windows laptops it is possible to deactivate the keyboard backlight using a combination of keys (usually you have to press the Fn key together with the F2 or F3 keys). These keys are easily recognizable because they usually have a dash with light rays on them.
On MacBooks, MacBook Airs, and MacBook Pros, however, you can turn off the keyboard backlight by holding down the F5 key, and you can turn it back on by pressing the F6 key.