Save energy on your Mac
Your Mac is designed to be energy efficient right out of the box, using features like Compressed Memory and App Nap to stay fast and save power. However, there are several ways you can further optimize energy usage.
Put your Mac to sleep
When in sleep, your Mac is still turned on, but it consumes much less energy. And waking your Mac from sleep takes less time than starting it up.
Put your Mac to sleep right away: On your Mac, choose Apple menu
Set your Mac to go to sleep after a period of inactivity: Follow the instructions in Schedule your Mac desktop computer to turn on or off.
Dim the display
Dim the display to the lowest comfortable level. For example, the display can be dimmer when you’re in a dark room than when you’re in bright sunlight.
To dim the display, press your keyboard’s brightness keys or use Displays preferences. See Change your Mac display’s brightness.
If you’re using a Mac notebook, you can also set your display to dim automatically when you’re using battery power. See Change Battery preferences on a Mac notebook.
Turn off Wi-Fi and Bluetooth
Turn off Bluetooth and Wi-Fi if you don’t need them. They consume energy even when they aren’t used.
Turn off Bluetooth: On your Mac, choose Apple menu
Open Bluetooth preferences for me
If Bluetooth is turned on, click Turn Bluetooth Off.
Turn off Wi-Fi: On your Mac, choose Apple menu
Open Network preferences for me
Select Wi-Fi in the list on the left. If Wi-Fi is turned on, click Turn Wi-Fi Off.
Disconnect devices and close apps
Accessories: Disconnect any accessories that you aren’t using, such as external hard drives.
CDs, DVDs, and connected external drives: Eject any CDs or DVDs you aren’t using. If you use an external drive, such as an Apple USB SuperDrive, disconnect it from your Mac.
Apps: Quit apps that you aren’t using. Even an app you aren’t using may be working in the background and consuming energy.
Get the most from your battery
On your Mac, choose Apple menu
Open Battery preferences for me
You can choose different sets of options depending on whether your Mac is plugged in. For example, you can choose to dim your display and put your Mac in sleep mode sooner when it’s using its battery. See Optimize energy settings for a Mac notebook.
Select other energy-saving options
In Energy Saver preferences, choose options that make it easier to save energy. For example, if you allow other computers to access the shared resources on your Mac—such as shared printers or Music playlists—while it’s in sleep you may be able to put your Mac to sleep more often.
On your Mac, choose Apple menu 
If you’re using a Mac desktop computer: Click Energy Saver.
If you’re using a Mac notebook: Click Battery.
For more information, see Set sleep and wake settings for your Mac.