Wow, you are paying a lot for electricity. Not bragging (actually I'm embarrassed) but the base rate up here in SW Oregon is $0.0356 per KWH. Very lucky I guess.
When we did new contruction years ago, an old trick was to run OSHA legal (mostly) zip cords places we were not supposed to run to. Could your builder be running
Juice where he should not be? Do not know if your new house has neighbors also under construction and could there be unknown usage you pay for? HB of CJ