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Stirfry2112

macrumors member
Original poster
Oct 13, 2009
31
1
Los Angeles
I was recently given a nahelm Mac Pro that i was going to setup as a html / dreamweaver / photoshop workstation. As i was preparing the computer, i got to thinking; should i even use this energy hog or just go out and buy an entry level m1 mac mini? Obviously the power usage between these two computers is significantly different but does anyone know how to accurately prove this theory? I have an old kilowatt meter but I’ve never researched how to use the numbers I get off the readings. Watts and amps all look wildly different between the two but how do i translate that into what i will actually be charged/savings on my energy bill? Just looking for real world/ tangible numbers to make sure i am not just falling back into old habits of tech lust.
 

Stirfry2112

macrumors member
Original poster
Oct 13, 2009
31
1
Los Angeles
Just to follow up, I did some calculating and the results were a bit surprising:

1 year of electric costs considering average usage of 8 hours, no sleep & shut down after 8 hours every day. kWh $0.11

Mac Mini 10w average = $3.21
Hackintosh 100w average = $32.14
MacPro 200w average = $64.28

These numbers do not account for external hard drives or display power usage, just computer average watts while under normal loads/ average usage. The amazing thing is, all of these computers are fairly close in terms of speed, with the Mac Pro being slower only with graphic tasks. Handbrake tends to render around the same time. However, even with the massive power reduction, it would still take a lot of time to recoup the $700 mini investment in power savings alone. But still amazing to see how far the industry has come in terms of efficiency in the last 10 years.

Also, here is a link to a very helpful calculator if anyone wants to do some around the house calculations and purchase justifications: https://www.rapidtables.com/calc/electric/electricity-calculator.html
 

apostolosdt

macrumors 6502
Dec 29, 2021
303
260
I used to have a 4,1 8-core, 16 GB RAM, all trays used, connected to a 24-inch Dell and a couple of external items like HDD and speakers. I noticed some extra power consumption in the electricity bill and I decided to check. I used a wattmeter for several months and the readings were consistent. So here's the numbers.

With 9 hours of regular use (Internet, music, LaTeX, documents, Skype, occasional movie watching, occasional use of superdrive, rare printing, no games or photoshop and the like); 15 hours of sleep mode (computer and monitor): Using max power value of 309 W and idle value of 146 W (official Apple numbers), calculation gives just under 150 kW/month; actual readings from wattmeter, average of 67 kW/month. I guess the difference occurs because the Mac is not using max power all the time it is running.

I hope that is useful info.
 

throAU

macrumors G3
Feb 13, 2012
9,103
7,257
Perth, Western Australia
Just to follow up, I did some calculating and the results were a bit surprising:

1 year of electric costs considering average usage of 8 hours, no sleep & shut down after 8 hours every day. kWh $0.11

Mac Mini 10w average = $3.21
Hackintosh 100w average = $32.14
MacPro 200w average = $64.28

These numbers do not account for external hard drives or display power usage, just computer average watts while under normal loads/ average usage. The amazing thing is, all of these computers are fairly close in terms of speed, with the Mac Pro being slower only with graphic tasks. Handbrake tends to render around the same time. However, even with the massive power reduction, it would still take a lot of time to recoup the $700 mini investment in power savings alone. But still amazing to see how far the industry has come in terms of efficiency in the last 10 years.

Also, here is a link to a very helpful calculator if anyone wants to do some around the house calculations and purchase justifications: https://www.rapidtables.com/calc/electric/electricity-calculator.html
The other thing to take into consideration is that if you're burning 200W on the Mac Pro, that will be dumped into the room as heat.

Which, if you live in a cold environment, is great.
If you're in a hot environment, that's an additional 200W of thermal dissipation you will need to cool with your air conditioner.

All that said, power consumption numbers don't generally justify an upgrade as you can see above - saving $60/yr would take you 20 years to recoup the cost of a MacBook Air...

However a new machine may well improve your performance significantly vs. something that old.
 
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mattspace

macrumors 68040
Jun 5, 2013
3,307
2,950
Australia
And for perspective - the amount of power an oven, or a toaster, or a clothes dryer, dishwasher (or water heater for hand washing) or a kettle will consume, that goes in the "it's not worth thinking about" category because it's not an avoidable usage.

If you want to think about environmental costs - the embodied energy of making even a mac mini will be significantly higher than its power savings over a ~1-4 year non-upgradable lifespan, vs continuing to use the Mac Pro. The aluminium in the case alone is going to be an astounding sunk energy cost.
 
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