HVAC One Year Follow Up

It's been a full year since our house went fully-electric!  With the new systems, there have been some struggles.  When we replaced the HVAC last year, we also went through a full house rewire, but haven't had a chance to completely reinsulate the attic yet!  So, I'll have a two-year follow up as well that will go over our energy usage after we revamp the insulation as part of the attic project.

That project is just barely underway, and we're definitely looking forward to having the space usable year-round even to help bolster our storage capacity.  More on that later!

December

Our largest energy bill was definitely in December.  When we were using on average of 90Kwh/day, we really had a problem.  The cost for that month was just under $350.  There were a lot of other things happening in December that bumped that bill up, so I definitely don't think it was all HVAC.  We were running holiday lights basically non-stop, even with all LED lights that's still a few Kilowatts.  We had many a marathon baking session running both ovens and lots of dishwasher loads.  We also had two full weeks of Winter Break, so there was a lot more running than normal.

Still, our HVAC definitely accounted for the majority of the energy usage.  Along with two full weeks of Winter Break, we also had two full weeks of temperatures below 0°F (-18°C). This was a pretty major cold snap, and it definitely tested our energy system.  Our biggest misstep was keeping our temperature at our autumn level above 70°F. 

January through Spring

Once we were through the December cold snap and had a better understanding of our system, we dropped the temperature to 68°F and rode out the winter.  I've written before that heat pump heat feels different: since it modulates the output air temperature to meet what the need is, the air coming through the vents doesn't always feel warm as it heats the house.  We wound up using the electric fireplaces a little more, but didn't have an electric bill above $250 for the rest of the winter. 

We know our electric fireplaces are more efficient than our back up blower so using those really helped to keep things a lot more comfortable as well as the overall heating costs down.  These aren't a perfect solution, but they are really helpful while heat pump technology continues to improve.  Other than December, making those adjustments brought our costs down below our previous average on a gas system.  With price increases last winter, we made out ahead!

Cooling Season

Both this spring and last autumn, the heat pump worked as expected with keeping the house cool.  Since it works like a standard condenser, it performed similarly to the last system.  We are dedicating more cooling to the parts of the house that weren't previously cooled, and that does mean we have increased the capacity of our system. 

Once we better insulate the rest of the basement ceiling and the attic, it will be easier to balance the cooling throughout the house.  The insulated rooms downstairs are already the coolest in the house in the summer and the warmest in the winter, so those really have become a testament to the insulation work we've done already. 

We have a bit more work to do!  But our over-under on switching to the all-electric Daikin system has more than paid off already.  Now that we understand the quirks of a different kind of system, I'm confident we'll keep getting our energy usage down.  And with our new solar system, we're in even better shape.  I can't wait to finalize the solar system next week!