M1 iMac Power Draw

[Miguel Cunha]

Hello, everyone!

Does anyone know the M1 iMac power draw?
I want connect it to a UPS and I need to know its electrical specifications. I fail to understand why aren't those written anywhere.
I'm also curious to compare it with the Intel equivalent, to assess the energy savings of the M1.

Thank you!

 

[PBG4 Dude]

It comes with a 143W power supply.

If you want accurate energy usage readings, get yourself A Kill-A-Watt and measure actual usage.

 

[Miguel Cunha]

Nice!
Thanks for the tip.

 

[colodane]

If you want accurate energy usage readings, get yourself A Kill-A-Watt and measure actual usage.

Yes, the Kill-A-Watt is excellent. I have one in my office and another for usage elsewhere.

Another convenient option for your Mac is iStat Menus. In addition to dozens of other useful performances parameters, it will measure total power consumption and display it on your menu bar. For instance, right now it is showing 37.5 Watts for my 27 inch iMac.

 

[DeltaMac]

Here's a link to Apple's support page listing a variety of iMacs, showing large energy use drops on M1 iMacs.

iMac power consumption and thermal output - Apple Support

Learn about the power consumption and thermal output (BTU) of iMac computers.

support.apple.com

Various third-party sites that list actual measured power consumption... Here's one: https://www.lifewire.com/the-new-imacs-power-adapter-has-a-secret-5180108.
That article concludes that a 143w power supply is certainly over-rated.
Looks like maximum power draw is less than 100w, and long term/average maximum should be less than 40w.
So, significantly less than half the energy draw of ANY intel iMac.

 

[Miguel Cunha]

Another convenient option for your Mac is iStat Menus.

I didn't know iStat Menus gauged that. Is always good to know.
Thank you.

 

[Miguel Cunha]

Here's a link to Apple's support page listing a variety of iMacs, showing large energy use drops on M1 iMacs.

iMac power consumption and thermal output - Apple Support

Learn about the power consumption and thermal output (BTU) of iMac computers.

support.apple.com

This is what I was looking for. Thank you very much for sharing.
The difference between ARM and Intel is huge!

Various third-party sites that list actual measured power consumption... Here's one: https://www.lifewire.com/the-new-imacs-power-adapter-has-a-secret-5180108.
That article concludes that a 143w power supply is certainly over-rated.
Looks like maximum power draw is less than 100w, and long term/average maximum should be less than 40w.
So, significantly less than half the energy draw of ANY intel iMac.

I can't wait to see what's coming!

 

[PBG4 Dude]

Here's a link to Apple's support page listing a variety of iMacs, showing large energy use drops on M1 iMacs.

iMac power consumption and thermal output - Apple Support

Learn about the power consumption and thermal output (BTU) of iMac computers.

support.apple.com

Various third-party sites that list actual measured power consumption... Here's one: https://www.lifewire.com/the-new-imacs-power-adapter-has-a-secret-5180108.
That article concludes that a 143w power supply is certainly over-rated.
Looks like maximum power draw is less than 100w, and long term/average maximum should be less than 40w.
So, significantly less than half the energy draw of ANY intel iMac.

The 8 core CPU in my 2020 iMac can take between 120-160W by itself when fully loaded, according to the Intel Power Gadget program.

 

[DeltaMac]

Your 2020 iMac would be an Intel processor, and the 120-160w looks reasonable for that processor.
And, pretty much follows from the chart on that Apple support page.

This thread is asking about M1 iMacs (which, of course, are most assuredly not Intel processors.)
Power Gadget can't run on M1, AFAIK.

 

[PBG4 Dude]

Does the Intel Power Gadget give accurate readings on a non-Intel CPU/Motherboard (?)

How does that compare with a dedicated power measurement device, such as a Kill-a-Watt meter?

The intel app is only worried about CPU stuff. It doesn’t measure total system power draw. I was pointing out the intel CPU in my 2020 iMac alone running full blast could possibly overdraw the 143W power supply used on the M1 iMacs.

 

[PBG4 Dude]

Your 2020 iMac would be an Intel processor, and the 120-160w looks reasonable for that processor.
And, pretty much follows from the chart on that Apple support page.

This thread is asking about M1 iMacs (which, of course, are most assuredly not Intel processors.)
Power Gadget can't run on M1, AFAIK.

I know. I was just comparing the intel CPU power draw alone to the entire M1 iMac. That’s all.

 

[uller6]

I have a kill-a-watt and I've used it to measure power consumption on my M1 iMac. ~14 watts idle with the screen on, ~44 watts running regular tasks during the workday. < 1W when sleeping. My old iMac Pro used ~240 watts when doing the same work. Replacing the iMac Pro with an M1 iMac saves me ~4 kWh/day in electricity, which adds up to almost $250/year in savings.

 

[colodane]

Thanks, uller6, for the measured power numbers for the M1 Mac. They look very encouraging!

The most significant improvement, of course, is for the operational power while performing tasks. The tasks and power will vary from user to user, but your data compared to the Mac Pro (approximately 200 watt improvement for your tasks) is one meaningful benchmark.

But I think your total energy savings might be overstated. Assuming 8 hours per day performing these "tasks", you would see about 1.6 KW-hr savings per day. Even if you used it every day for an entire year you would see about 580 KW-hr total savings. At 10 cents per KW-hr that would result in about $58 savings per year.

But the power decrease is significant! Setting aside the cost savings, the M1 machine will be running cooler and quieter. Reliability should be improved.

Thanks again for the data. It will be interesting to see similar comparisons of the M1 vs. late vintage non-Pro iMacs.

 

[uller6]

Thanks, uller6, for the measured power numbers for the M1 Mac. They look very encouraging!

The most significant improvement, of course, is for the operational power while performing tasks. The tasks and power will vary from user to user, but your data compared to the Mac Pro (approximately 200 watt improvement for your tasks) is one meaningful benchmark.

But I think your total energy savings might be overstated. Assuming 8 hours per day performing these "tasks", you would see about 1.6 KW-hr savings per day. Even if you used it every day for an entire year you would see about 580 KW-hr total savings. At 10 cents per KW-hr that would result in about $58 savings per year.

But the power decrease is significant! Setting aside the cost savings, the M1 machine will be running cooler and quieter. Reliability should be improved.

Thanks again for the data. It will be interesting to see similar comparisons of the M1 vs. late vintage non-Pro iMacs.

My computer is on for "work" closer to 17 hours a day, 7 days a week (7 am - midnight). I measured the ~4kWh/day savings directly from my electric company usage information averaged over a week after switching computers. And, where do you live where electricity is so cheap?!? I want some! I pay 22 cents / kWh.