Looking for a way to mimic the battery-saving behavior of closing the lid without actually doing so
You can find these options in System Preferences > Energy Saver.

Drag the "Computer Sleep:" slider to the left.



Note that for newer Apple portables, Yosemite combines the sleep and display sleep option:

http://forums.macrumors.com/threads/2013-mba-no-computer-sleep-setting-wtf-heres-why.1598329/