COST OF OPERATION
As you might have guessed if you've read either the "Basics" or "Efficiencies" tab on this website, the cost of operating a heat pump is the cost of buying electricity to run it. For the sake of simplicity, the costs estimated here will only look at the full-time operation of a heat pump and will not include the costs associated with your other fuel system, be it gas, heating oil, propane, or other electric since these will be too varied, depending highly on what temperatures you experience. This tab will just look at the cost of operating a heat pump in isolation from other systems.
The cost of running a heat pump will vary widely depending on several factors: the cost of electricity where you live, the heat loss from your home, and the efficiencies of the heat pump.
For the purpose of this exercise, we will use electricity costs of Eversource in Connecticut, which is 22.8 cents/KWhr as of Jan. 1, 2019.
For equipment, we'll use the same Fujitsu model we saw in the Efficiencies Tab, a FO314RSJ outdoor unit married with a FH3617TTDS*SN indoor air handler. The assumptions we'll be using for this calculation are:
Region V - Connecticut
$0.228/KWhr electricity cost
Cooling load hours: 600
Heating load hours: 2500
Building heat loss: 40,000 BTU/hr
Fujitsu SEER: 14.0
Fujitsu HSPF: 8.2
Heating capacity @ 47 degree F: 24,000 BTU/hr
Though this website isn't focused on cooling, the ICP calculator we use calculates cooling costs anyway. Note if we move the geographic region further south, the cooling load hours will go up and the heating load hours will go down and vice versa if we move further north of Region V.
Summer cooling: $235
Winter heating: $2,573
You can compare these costs to what you're paying now - typically replacing a window-installed air conditioner for summer use, or supplementing a heating oil, propane, gas or electric heating system in the winter (which as we mentioned you may still need to run).
Next we look at a so-called cold-climate heat pump, the Mitsubishi MXZ-3C24NAHZ like the one pictured below, right. We keep the same housing, electric costs and geographic parameters as with the Fujitsu unit above, but change the equipment ratings for the Mitsubishi as follows:
Heating capacity @ 47 degree F: 30,600 BTU/hr running at maximum capacity
Summer cooling: $265
Winter heating: $2,266
As a more efficient unit than the Fujitsu, the Mitsubish costs about 12% less to run during the heating season. It may not sound like a lot, but remember, with it's bigger compressor uses more electricity, on the one hand, but on the other, this heat pump is less affected by cold temps and continues to run in sub-freezing conditions. In fact this model's thermal balance point is at 24.4 degrees F. compared to Fujitsu's 31.7 degrees as explained under the Efficiencies tab.