This is the term referring to when someone's sole objective is to get blacked out as soon as possible, preferably within an hour.
Being "blacked out" is of course referencing the act of drinking so much one experiences amnesia and forgets all the dumb shit they do following the black out.
A much more aggressive take on the traditional power hour.
"Man, i just got fired from work, you down to power black out?"

"Did that guy just take 8 shots of tequila in a row?
Ya, he's attempting to power blackout before his ex-girlfriend gets here"
by KangaRooMar April 28, 2013
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