I get 44W at 40 A and 13W at 12 A. But I'm also an ME, hahaha. Even so, 44W is too high.
God as my witness, this same circuit has supported a NEMA 14-50 plug-in EVSE for like 10 years now. THe only difference is the plug is gone, and lugs have been crimped on to the end.
But, I can't argue...