Previous 1 2 3 Next 37 Replies Latest reply: Oct 5, 2005 1:25 PM by Eckhard Giere
Peter Schaufuss Level 1 Level 1 (125 points)
Our electrical bills where getting top high, so i decided to check the power consumption of our different electrical devices using a small utility you plug in between the equipment and the power outlet, which will show you how many Watts are being drawn at any given moment.

On my dual 1.8 G5 (2003 model) I noticed that the power consumption was very high.

In sleep mode it was about 40W and when turned off it was still 32W!!!

According to Apple's specifications the numbers should be closer to 10W for sleep and 2W for off.

The only way I can get lower than 32W consumption is to pull the plug!

I found a usegroup entry with a guy with similar data, but there was no solution to the problem.

click here

Does anybody have any suggestions? - or can you maybe measure your own G5's to see what yours are using?

I also found that when the machine is ON, with no processor hungry programs running, it uses around 200W - which on a yearly basis adds up to almost 2000 KWh if I leave it on all the time.

I was under the impression that Apples machines where energy friendly???

I really don't feel like powering the machine down AND pulling the plug everytime I'm not using it, so I hope someone can come up with an answer.

  • Bhagiratha Level 2 Level 2 (420 points)
    How did you test the power consumption of the machine? How did you find out that it was using about 200W?

    I also was wondering how much of power my G5 was consumming.

    Is there some device or software that can help find that info.

  • Tom Nelson1 Level 4 Level 4 (2,550 points)
    First question is...

    What is the configuration of your G5? Amount of RAM, number of hard drives, speed of hard drives, video card, any PCI cards.

    Were any peripherals attached, that are powered by the Mac, such as scanners, hubs, docking stations, Etc.

    Are you using a UPS or surge suppressor, and was that inline when you were doing your test.

    Any of the above would change the amount of current drawn by your Mac. In most cases the problem is a parasitic load that is not accounted for in the testing.

    Tom N.
  • Peter Schaufuss Level 1 Level 1 (125 points)
    I used a device you plug into to the power outlet and then you plug the computer into that and it will show you how many watts are used. You can also program the price pr. KWh and have it calculate the daily, monthly and yearly cost based on the average power consumtion of the unit plugged in.

    The configuration of my Mac is in my signature - besides that I also have an AlchemyTV PCI card + a PCI USB card installed and a Edirol PC300 keyboard, A BT dongle, A logitech wireless mouse and a Canon S600 printer attached to the USB card.

    I'll try to unplug all external units except the keyboard and see if it makes a difference.
  • Peter Schaufuss Level 1 Level 1 (125 points)

    I tried unplugging all external units and also disconnected the monitor (an ACER LCD connected via an ADC->DVI converter) still the same.

    I wonder if the AlchemyTV PCI card or the generic USB2 PCI card could be the problem?
  • VAIO Level 4 Level 4 (1,215 points)
    The G5 below has these readings (240 volts):

    Off - 33.6 W

    Sleep - 40.8 W

    Idle - 204 W

    I'm glad of the warmth actually, as the boiler is on the blink:

    Think what you're actually measuring is Amps, and converting it.
  • dadof3 Level 4 Level 4 (1,675 points)
    I havent read much about the on/off/idle wattage loads of the G5 but I'm an electrician and get asked alot "how much will all that landscape lighting cost me a month? " so I have to calculate it for them.

    It's a pleasent surprise to read your finding is only 2000 KWh per year.

    That works out to a meer $200 per year at our residential rate of .10 cents per KWh, or .06 cents per day.

    Have you tried testing that wattage meter for accuracy with a known load of something like a 75 watt light bulb?

    Your system idle:
    200 watts X 24 hours = 4800 watts or 4.8 KWh
    4.8 X 365 days = 1,752 KWh

    1,752 KWh is cheap.

    I know your question was wondering why the sleep and off loads are higher than expected, but $200 a year is a bargain.

    I'm curious, so let us know what you find after testing the meter with a light bulb.
  • dadof3 Level 4 Level 4 (1,675 points)

    I've found most our customers have a misconception that they're computers are causing high electrical bills.

    Apparently some of this idea comes from many years back when computers were looked at as a novelty and voodoo because most people didnt understand what they are.

    In reality, most the increased cost caused by computers is the increased cooling loads generated by the box and monitor.
    That's why my CRT only gets turned on when I need it. The office will climb over 80 degrees F in a couple hours with the room closed if I dont.

    Look here for the source of your high electric bill and anywhere else that could be attributing to it like a old refrigerator or electric ovens and dryers.

    edit: something doesnt appear to be right with the math too.
    should be approx .60 cents per day
  • Peter Schaufuss Level 1 Level 1 (125 points)
    You might find 2000KWh pr year to be a low number, but our households total usage is 5200 KWh pr. year so it's more than 30% of the total usage.

    According to statistics our electrical usage should be closer to 4200KWh / year so 2000KWh IS a lot (maybe not in the US, but for a Danish household it's quite high).

    But no matter what it doesn't change the fact that according to Apple the power consumption SHOULD be much lower:

    So even though you think $200 / year is cheap (the price in Denmark is closer to $500 for that amount of electricity - NOT CHEAP) that's beside the point, because the machine IS using much more power than it should, and as you can see from a post above, I'm not the only one with these figures.

    The questions is - Is Apple lying on the page referenced above, or is there something wrong with our machines?

  • VAIO Level 4 Level 4 (1,215 points)
    Reference measurements (240volt) - Fluke digital multimeter

    60watt tungsten lamp - 55.2 W

    100watt tungsten lamp - 96 W

    2 x 500watt tungsten/quartz/iodine/halogen lamp
    A - 458.4 W
    B - 482.4 W

    1050watt(nom.) toaster - 1012.8 W

    laserprinter 480watt (nom.)
    idle - 7.3 W
    printing(avg.) - 384 W
    peak load - 592.8 W

    So that's why APC advise not to connect laserprinters to the UPS...

    And... the Mac via APC Smart-UPS 750VA (240volt):

    Off - 100.8 W
    Sleep - 108 W
    Idle - 256.8 W

    compared to Mac only:

    Off - 33.6 W
    Sleep - 40.8 W
    Idle - 204 W
  • Rick Prather Level 3 Level 3 (720 points)
    So you're saying that the APC UPS adds over 60 W's to your sleeping Mac's consumption?

    Is that with a fully charged battery?

    If not, that seems to be an even more interesting revelation from all this than the "Off" consumption of the PM.
  • John Fallon Level 2 Level 2 (310 points)
    This morning, I plugged one of those gadgets into my APC RS1000 UPS, which handles the SP PowerMac G5, the Sony CRT monitor, and a 14 inch iBook. With iBook, G5, and monitor on, but not doing anything CPU intensive, the total wattage was around 250-260. (I have the CPU performance setting at "highest".)

    Shutting off the computers, but with the monitor still on brought it down to 85 watts or so. After a minute or so, the monitor went to power saving mode, and the total consumption dropped to 23 watts. I guess that's the residual load with a trickle charge into the APC and into the iBook battery. If the batteries were recharging I'd expect the usage would be higher.

    The SP G5 does seem to use a lot less current than my older Athlon 2700+ box, which can keep the temperature up 5-10 degrees even on a cold windy day.
  • Jason Titus Level 1 Level 1 (0 points)
    I've been noticing this as well. My Dual 2ghz G5 is pulling ~170W sitting idle. This is as opposed to my Sawtooth G4 1.4ghz (w/ upgrade) which runs at ~50watts idle, and my dual 550mhz PIII server (currently w/o drives) which is also pulling ~50 watts idle. Makes me a bit guilty about using my G5 so much.

    While sleeping the G5 does drop to 10 watts, so that isn't as bad. Looking forward to an Intel Merom/Pentium based future....

  • Tom Nelson1 Level 4 Level 4 (2,550 points)
    Since we are talking about energy consumption, I'd like to ask a related question...

    Why do so many people leave their computer on, usually in sleep mode? I've always turned my computers off when not in use. This certainly get around the issue of power draw when not in use!

    Tom N.
  • Rick Prather Level 3 Level 3 (720 points)
    Not according to the interesting figures above!

    The difference between "Off" and "Sleep" is very small.

    I like the ability to have the nearly instantaneous off and on that I get with "Sleep"
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