How much power does a Mac use when it's sleeping

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Level 1

7 points

How much power does a Mac use when it's sleeping

I recently asked about shutting down vs. sleeping a computer at night. Now I'm wondering how much power it uses sleeeping. I have a laptop which I imagine is pretty dormant. What about a desktop-- Intel Mac?

MacBook Pro, Mac OS X (10.6.1)

Posted on Mar 24, 2011 1:20 PM

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Answer 1

gumsie

Level 4

2,185 points

Mar 24, 2011 1:36 PM in response to imcarmel

Depends what you mean by desktop. If you mean iMac I can't help you. If you mean Mac Pro;
9W/55VA sleeping, (PF 0.16)
242W/263VA idle, (PF 0.92).

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Answer 2

imcarmel Author

Level 1

7 points

Mar 24, 2011 1:45 PM in response to gumsie

What does that translate into 🙂 like in x hours of a 100 watt light bulb or some such?
am I right that a laptop uses almost nothing overnight?

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Answer 3

gumsie

Level 4

2,185 points

Mar 24, 2011 2:04 PM in response to imcarmel

I can tell you nothing about a laptop as I don't see a way of measuring what it's using while asleep. As for the desktop you are pretty much spot on, You can use it for about 11 times longer than a 100W light bulb for the same money.
In fact by using one of those price comparison websites I work out that it'd cost, (@ 10.17p/KWH), [24x365] x 0.009 x 0.1017 = £8.018 if it was left on standby all the time for a full year.

That excludes things like a standing charge for the electricity, and assumes you were on the Fixed S@ver Dual Fuel plan from EDF Energy.

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Answer 4

captfred

Level 7

26,446 points

Mar 24, 2011 2:12 PM in response to imcarmel

Power Consumption for 27-inch iMac
Mode 100V 115V 230V
Off 0.85W 0.88W 0.90W
Sleep 1.44W 1.42W 1.53W

A 100 watt light bulb uses 70 times the power of a sleeping iMac !!

Regards

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Answer 5

Mar 24, 2011 2:15 PM in response to captfred

And a turned off iMac uses infinitely more power than a turned off 100W bulb!! 😉

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Answer 6

Camelot

Level 9

58,719 points

Mar 24, 2011 4:27 PM in response to Martin Pace

And a turned off iMac uses infinitely more power than a turned off 100W bulb!!

If we're playing that game, the power-on/POST/spin-up/boot process uses the same power as several hours of sleep time, so if you're only going to be off for a short period then sleeping is better than turning off.

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