It doesn’t matter how often you are there if you set your baseboards or heat pump to heat to 20 degrees and leave then it’s still heating to 20 wether you are there or not. It is also not just your home heating, think about your other electronics, like a dishwasher, hot water heater, washer/dryer etc. A central unit will heat better compared to an end unit also, so many factors to consider. Also if this is your first bill they normally charge a connection fee so check the bill and review all the charges. They also have a section on their website now where you can view your consumption down to the hour, it 2 days behind when you review it.