I think the default hibernate mode is "3". This is the safe sleep mode where the computer goes into normal sleep, but if the battery drains to a given level, it writes the contents of the RAM to disk and then hibernates.
Hibernate Mode 25 is supposed to act similarly, except that it hibernates after a given period of time, about 70 min. I find this does not work on a MacBook Pro. Seems to just hibernate immediatly rather than sleeping. Good for battery life, but a pain when youo want to wake the computer.
You can get the "state" of the hibernate features by typing
pmset -g
into terminal.
You can set the hibernate mode with:
sudo pmset -a hibernate mode 25
(or 3 for hibernate mode 3)
In the end, I downloaded "DeepSleep" from the app store. When you launch it it puts the computer in Hibernate mode. The computer sleeps normally for mode 3 otherwise.
One note of caution, DeepSleep occasionally hangs up on wake. This leaves the Hibernate mode set to 25 and you'll need to use the sudo command above to put it back in Hibernate mode 3.
Hope this helps.
