MacOS – How effective is Deep Sleep Mode

To disable deep sleep, run the following command in Terminal:

sudo pmset -a standby 0

This is a description of "standby" (deep sleep) from the pmset man page:

 standby causes kernel power management to automatically hibernate a
 machine after it has slept for a specified time period. This saves power
 while asleep. This setting defaults to ON for supported hardware. The
 setting standby will be visible in pmset -g if the feature is supported
 on this machine.

 standby only works if hibernation is turned on to hibernatemode 3 or 25.

 standbydelay specifies the delay, in seconds, before writing the hiberna-
 tion image to disk and powering off memory for Standby.

Battery savings depend on how much time your Mac spends in standby. While in standby mode, your Mac consumes 0 power, it's as if it is shut down (note: not taking Power Nap into consideration).

My personal recommendation would be to set the "standbydelay" value to something bigger. 2 hours, for example. This means that if you open the lid back in less than 2 hours, your Mac would be in regular sleep and wake up instantly. If longer than 2 hours, your Mac would enter standby mode and consume no power, and waking up will take a bit longer.

Example for 2 hours:

sudo pmset -a standbydelay 7200

Retina MacBook Pros and newer MacBook Airs actually do that by default under certain conditions. If Power Nap is disabled, the computer is on battery power, not connected to USB devices and not paired with Bluetooth devices, it enters standby mode (hibernation) after about 70 minutes of normal sleep.

If pmset -g | grep standby looks like this, your computer supports standby mode:

 standby              1
 standbydelay         4200

You can change the delay to 15 minutes with sudo pmset -b standbydelay 900.