I have been using an electrical metering device called "The Energy Detective" www.theenergydetective.com which has worked very well. Easy to install and can be located anywhere in the building. Stores the data and displays it in different formats. Here is the KW usage per day since March 07. Pretty much averaging 3.8 KW per day.
Below is the data in graph form of the inside, outside, in and out humidity since Oct 07. I used an analog thermostat till about March which on the inside temp line, it smoothed out with the new digital thermostat.
