I pulled our handy little Killawatt out from its resting place this week and used it to track our 27" iMac's (quad core i7 processor) electricity usage. The Killawatt plugs in between the wall socket and the device you want to monitor. It will calculate cumulative power consumption (Kwh), watts, amps, etc. The device is particularly useful in figuring out how much an electric appliance, or computer, really costs to run.
|
27” Apple iMac | ||||
|
Activity |
Amps |
Kwh |
Kwh / Day |
Cost / Day |
|
Off |
0.02 |
0.0024 |
0.0576 |
$0.01 |
|
On, screen dark |
0.45 |
0.054 |
1.296 |
$0.16 |
|
On, light usage |
0.8 |
0.096 |
2.304 |
$0.28 |
|
On, max usage |
1.7 |
0.204 |
4.896 |
$0.59 |
"Max usage" means all CPUs were chugging away and a DVD was playing. Cost / day is based on my current cost of just under $0.12/Kwh.
Overall that doesn't feel too bad, though it can add up over a year. If you were compressing videos 24x7 non-stop for a whole year it would cost you over $210 (and would probably seriously reduce the lifespan of your iMac to boot :-)