When I did a Google search I found where it said turning a work pc off for 12 hours per night saves 3 dollars a month! I am guessing a work pc is similar to a pc running Boinc, heavy use for most of the day. Although since Boinc is 100% of the cpu 100% of the time Boinc may use it a bit more. I am not turning mine off, but have turned off some of the slower machines as I get newer and faster ones.

I wonder if they considered the cost of the worker turning on and authenticating to the computer every morning?

FTE (hourly fulltime employee) with benefits is $15+/hr.
20 weekdays x 1 minute (power up/login) = 20 minutes/month.

Not that the worker would start working once they did get to their office, but, at least there is one less obstacle in the morning for them in order to start working.

The one problem I saw noted was the wear and tear on the hardware by the constant power cycling of it. They noted an increase in the repair costs as a result of it. My work is keeping a strict log of all problems with the pc's during this first year and say they will re-evaluate. I think the power company will have alot to say about it, if it saved them money the on/off will continue, if not it will probably stop. What my work does is auto turn off the pc every night and then auto turn it on again every morning. So all the user ever sees is a running pc. The pc shuts down every nite at 7PM, unless the user manually aborts the process by clicking the box, and then the pc auto turns on at 6 to 6:30 AM. We did have to identify those pc's used 24 hours and they do not shut down.