Bad current sensor.
All of that power should be showing up as heat somewhere.
What is the rating of the circuit breaker feeding the furnace? How long does the furnace run for?
Is the furnace running under similar conditions as last year (indoor and outdoor temperatures)?
Is there any possibility the the conductors to the furnace have been damaged?
A short in an element should trip a breaker.
Anyways what is the power output of your furnace? Does it have a label with a rating?
This website says a typical residential furnace might consume 18kW. So an increase of 12kW does not seem unreasonable.Electricity usage of an Electric Furnace - Energy Use Calculator
And kW*h are units for energy.
When your furnace is on, is your forced air system on as well? And is your gadget measuring that as well? If so, is there a difference there from when you last measured - like a dirty filter maybe?
Yes, it’s a forced air/electric element furnace system. It’s just that last year, the most juice used when the heat was on was about 11-12 kw. This year, it’s almost twice that. I can’t figure out what all the info on the furnace is telling me except that the largest number of kw listed is 11-13. I gotta get someone to look at the furnace.
Start by looking at your furnace’s name plate. It should give you the max load that the furnace consumes.
What is the amp rating of the breaker to the furnace?
What is your house’s main panel ratting?
It would be better if you could get a amp probe to test the draw.
Also what voltage, I think we are all assuming 240 VAC.
I just had another thought. You said your meter measures KW not KWH right. To get KW the meter would have to be measuring both the amp draw and the voltage. But if it is measuring only the amp draw and is assuming the voltage is 120 VAC or 240 VAC then it can still calculate the KW, but there probably is a switch on the meter for either 120 VAC or 240 VAC did you have the switch in the wrong place either this year or last?
One of the largest number of KW listed is 12-13. Is there a second large KW listing? If you have 2 stage heating the name plate should list both.
As has been mentioned, if more electricity is being consumed, more heat is being produced somewhere, or else there is a massive amount of static electricity (or capacitance) built up somehow. If you were somehow actually using twice as much electricity heating your home, the temperature should be on average a bit higher than normal (and then slowly leak out the environment where it gets wasted).
Ok - it sounds as if this is a job for an electrician/furnace guy. This electricity stuff is above my pay (and intelligence) grade.
Can you compare utility bills 2014, 2015, 2016?