Wonder if anyone know how to calculate how much electricity it costs to run an iMac 5K for a year.
Let's say you use the iMac 5K for 12 hours a day. What is your electricity bill in a year?
This will depend on two things:
(1) The actual power consumption based on your usage. On my 2015 iMac 27 just sitting there it pulls 95 watts, including the two external RAID arrays. When rendering video in FCPX it pulls about 150 watts but that is brief. It drops to about 80 watts when sleeping but that also includes the RAID arrays. That is based on direct measurements of my iMac.
The long term average of an iMac 27 with no external drives might be about 90-95 watts, including modest sustained usage. However a USB bus-powered HDD only pulls about 2-3 watts.
If it sleeps a lot it would be less. In general 95 watts sustained is probably close to the high limit of what the average person would do over time, so I will use that number.
(2) Your local cost of electricity. The U.S. average is 12 cents per kilowatt hr, but this varies widely by state. In Hawaii it's 35 cents per Kwh, in New York it's 19 cents, in Washington State it is 8.5 cents per Kwh. Details:
https://www.electricchoice.com/electricity-prices-by-state/
If we use an average iMac power consumption of 95 watts, for 12 hrs this is 95 watts * 12 hr = 1,140 watt hrs.
Using the US average of 12 cents per Kwh, this would cost 0.12 per Kwh * 1.14 Kwh = about 14 cents per 12-hr usage day.
A year would be 365 times that, assuming it was used the same amount each day, or 365 * 0.14 = or $51.10.
If you lived in Hawaii that would cost about 40 cents per day or $146 per year.
If you lived in New York State that would cost about 21.7 cents per day or $79.20 per year.
If you lived in Washington State it would cost about 9.7 cents per day or $35.40 per year.