Jenn-I run into this issue occasionally myself, and being in the North East, electricity is at a premium. An older refrigerator is usually the culprit if it is, in fact, an appliance. A refridgerator is responsible for up to %15 of an electric bill. Have they been running the air conditioning extra cool? Also, big screen tvs, computors and different electronics all on at the same time will spike power usage. Good luck getting a straight story-Bruce