If you only do one thing, do this. The biggest power hog in your laptop is, by far, the screen. The brighter it is, the more power it consumes. Unless you’re working under direct sunlight, you probably don’t need it at its highest setting.
Lowering the brightness is as simple as tapping a function key at the top of your keyboard and is the single most effective way to immediately extend your battery life.
“When you first turn the brightness down to, say, 50 percent, you might say, ‘Oh, this isn’t bright enough,’ but about 10 seconds later your eyes adjust and it’s totally fine,” says Mike Nash, former chief customer experience officer at HP. “If you’re just doing email or something on a dimly lit plane, cranking the screen down will have a dramatic impact on how long your battery lasts.”
