How did you manage to consume 7KwH in just one day using only two computers?
Laser printer added some, no doubt. But... do you know why I have three
6-port USB hubs on the back wall of my computer hutch? Because two
aren't enough. 60-ppm scanner, webcam, speaker system with subwoofer (not USB but drawing power), two external hard drives to go with the four
internal drives, a 27" monitor, an incandescent lamp to light up my work area, it all adds up.
Mostly, though, because I like to keep the two electric meters in sync (God only knows why, I guess I'm a bit OCD) I occasionally plug my rather large side-by-side refrigerator into the computer circuit to even things out. Note that the "A" meter is less than usual while the "C" meter is more on that day. Also, the air conditioner shares both
meters (it's 220 volt so it gets one leg from each circuit) so that could have run up the tally if we used it that day. It probably gets used about 10 hours a year, and the heating system another 10. The air conditioner is heat pump so it just runs in reverse for heat.
The meters are the digital kind that automatically send the meter readings to the billing office, and on one day (December 28, 2013) my two meters and the meter for the apartment downstairs (those are the only three that I track) all showed six times the normal daily consumption.
I suspect that CFE "tweaked" everybody's meter that day for reasons unknown, hoping that nobody would notice. It only ever happened that one time, but if it happens again I will raise some hell about it.