I understand. I think it gets a little more complicated though because of the potential that attractions aren't simply turned off while the park is closed. For some maintenance work, and certainly testing, during off-hours I would expect the power draw to be the same. How many hours overnight is this done? Are they cutting back EMH hours to save money or to increase opportunity for maintenance? (I suspect the answer is probably to save money, or possibly a mix of both.) The CM wage savings is obvious and fairly straightforward, this less so.
Did I really just spend several minutes of my lunch hour discussing this?
ETA: I see
Cafeen is thinking along the same lines.
Also, know that I work with complicated computerized systems that rival some WDW attractions and are in use during the day, and then are turned over at night for a maintenance shift. In my case, most of these systems remain on 24/7/365, and are only shut down when specific maintence procedures call for it.