How Much Energy Does Sleep Save?

Felasco

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Original poster
Oct 19, 2012
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Ok, here's a baby novice question I've been meaning to ask for some time.

When you put a Mac to sleep, how much battery power does it save?

Does a Mac use 75% of normal battery usage when asleep? 50%? 25%? Other?

A ballpark answer will do, thanks in advance.
 

ApfelKuchen

macrumors 68040
Aug 28, 2012
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Ok, here's a baby novice question I've been meaning to ask for some time.

When you put a Mac to sleep, how much battery power does it save?

Does a Mac use 75% of normal battery usage when asleep? 50%? 25%? Other?

A ballpark answer will do, thanks in advance.
Ballpark? Way, way less than 25%. The display is the biggest eater of batteries - it's off. If your machine has a hard drive, the hard drive will be off. Wi-Fi is turned off, apps that have been running are suspended, etc. http://support.apple.com/kb/HT5963

The specs for today's MacBooks peg battery life at 30 days when in Standby. Consider Standby to be deep sleep - by definition, if 2013 MacBook has been asleep for 3 hours, it drops into Standby. Older models drop into Standby after an hour asleep. http://support.apple.com/kb/HT4392
 

maflynn

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May 3, 2009
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Sleep keeps the ram powered so you don't lose its contents. Probably a few other components but all in all everything else has its power shut off, so its only sipping the battery a tiny bit.

As stated by ApfelKuchen, deep sleep (or as apple calls it standby mode) will save power as the contents of the ram are saved to storage and thus even more power is saved
 

Felasco

Guest
Original poster
Oct 19, 2012
417
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Thanks for the education guys, appreciate it, I am now a bigger fan of sleep and will use it more often. Before this thread I was never quite sure what I was accomplishing.
 

Mrbobb

macrumors 601
Aug 27, 2012
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I read this thread and I go SAY WHAT?

Sleep saves power? as versus what, fully awake? (seems too obvious).

So I still don't know what's the purpose of the original question.
 

ApfelKuchen

macrumors 68040
Aug 28, 2012
3,214
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Between the coasts
I read this thread and I go SAY WHAT?

Sleep saves power? as versus what, fully awake? (seems too obvious).

So I still don't know what's the purpose of the original question.
Forums exist, in part, to share information - questions asked, questions answered. I've learned a whole lot over the years from so-called basic questions - none of us has fully comprehensive knowledge.

Purpose of this question? Say it takes a while for your computer to wake from sleep. You just might wonder whether the waiting is worthwhile, or whether to disable sleep mode and be done with the delay. On a desktop, you might not mind spending the extra kilowatt hours. If you're running a laptop on battery?