It’s important to keep track of your power consumption on a Macbook Air or Pro, since that will determine how long you can use the thing before you have to plug it in again. Mavericks makes it easy to see the top app or two that uses the most energy on your Mac with a quick Option-Click on the battery menubar icon, letting you know which apps are consuming the most energy.
If you want to know about all the apps running on your Mac, though, you’ll need to dig a bit deeper, using Activity Monitor.
Launch this super helpful utility from the Utilities folder, which is typically in the Applications folder. Once launched, you’ll see a few tabs across the top, including CPU, Memory, Energy, Disk, and Network. Each tab contains detailed information on what your Mac is doing at any given time.
To check out the energy usage of your running apps, simply click on the Energy tab at the top. You’ll get a nice list of all the apps running on your Mac, even the background ones. Now, click on the “Energy Impact” column to sort your apps into the order of most energy being used. Typically, you’ll see the main apps you’re running near the top, like your web browser, iTunes, etc. Further down the list are apps that use less energy or are idle in the background.
It’s a great way to figure out what might be eating up your battery life, if you’re trying to eke out that last bit of power in the coffee shop and there are no tables near an outlet open.