What grandparent commenter showed was the school district's numbers are plausible. I doubt the district entered into a legal battle without first consulting an engineer or two about the electric costs.

Yes, it will draw even more than 350 Watts at full load. 350 is the output power, whereas incandescent lightbulbs are measured in input power. So a 350 watt power supply, depending on efficiency of the PSU anyway, is probably using around 400-500 Watts at the wall at full load.

You are right. I was just going off the source I found, which accounted for some of the aspects you point out, but not all. These numbers simply provide a rough estimate, and detail how the sys admin certainly did cost the school district real (and potentially very substantial) sums of money.

> Even more complicated is the heat.

You make a good case for the winter months, but the opposite would hold true for the summer months when the heat becomes a real issue and additional air conditioning may be necessary, etc...

> Edit: also if it was a public school, wouldn't they be off for about 3 months over summer ?

Not necessarily. Usually over the summer months (for a traditional schedule school as opposed to a year-round schedule like many public schools are these days) some of the staff is typically on campus monday-friday doing various administrative tasks, workshops, prepping for the next school session, moving classroom furniture, cleaning, etc... IT staff would be included in this, and therefore we can reasonably assume the sys admin was still running his systems.

They may be off for 3 months over the summer. Which might mean they were actually off, or it might mean that they ran 24/7 and NONE of that time was for 'educational' purposes.