Well, it turns out our furnace is using much more electricity than it should be. We apparently had some sort of malfunction that we only caught because the temp here went below zero this week, and despite the furnace running constantly, the house never made it above 56 degrees. Frustrating to say the least.
It turns out the thermostat was not telling the furnace to turn on the auxilliary heat when the geothermal couldn't keep up, even though the thermostat sad the auxilliary heat is running. So, after about two hours of work, we finally got the furnace and the thermostat to talk to each other today. One problem solved.
I think this will help with the furnace's electric usage, because even though it's still near zero out, the house is warm AND the furnace actually has cycled off a few times. Before, it was running constantly and the house was still freezing. I hope this cuts its electric use significantly, but I am trying not to hold my breath.
Guess I got more than I bargained for for that service call.