Change Energy Saver preferences on Mac
Use Energy Saver System Preferences to set options that control your computer’s energy use. If you have a portable Mac, these options also help you extend your battery’s life.
As an ENERGY STAR® partner, Apple has determined that standard configurations of your Mac meet the ENERGY STAR® guidelines for energy efficiency.
For more information about ENERGY STAR, see the ENERGY STAR website.
Important: The table below lists all of the options available in the Energy Saver pane of System Preferences. Because the features of the computer you’re using determine the options shown, you may not see all the options listed below.
To open the pane, choose Apple menu 
> System Preferences, then click Energy Saver.
Open Energy Saver preferences for me
Battery, Power Adapter, and UPS | Click Battery, Power Adapter, or UPS, then select energy-saving options for that power source. Your Mac will use those options when it’s getting power from that source. You see the Battery button only if you have a portable Mac. You see the UPS button only if your Mac is connected to an uninterruptible power source. |
Automatic graphics switching | To extend the life of your battery, set your Mac to automatically switch between graphics modes. |
“Computer sleep” and “Display sleep” sliders, or “Turn display off after” slider | Drag the slider to set the amount of time your computer or display should wait before going to sleep. |
Put hard disks to sleep when possible | Put the computer’s hard disk to sleep whenever it’s inactive. |
Wake for network access | Users can access your computer’s shared resources, such as shared printers or iTunes playlists, even when your computer is in sleep mode. |
Slightly dim the display while on battery power | Reduce the brightness of the display while on battery power. |
Enable Power Nap while on battery power Enable Power Nap while plugged into a power adapter | Permits your computer to check for email, calendar, and other iCloud updates while sleeping. When your Mac is plugged into a power adapter, Power Nap can also do Time Machine backups. |
Allow power button to put computer to sleep | Allows you to press the power button to put your computer to sleep. |
Prevent computer from sleeping automatically when the display is off | Prevents the computer from going to sleep when the display sleeps. |
Start up automatically after a power failure | Start up your Mac after a power interruption. |
Show battery status in menu bar | Shows the battery icon in the menu bar. The battery icon shows when your portable Mac is connected to a power supply and the battery is charging |
Schedule | Set a daily schedule for putting your Mac to sleep or turning it off and on. |
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