This calculator estimates the running-cost saving of replacing plug-in or other heating with a heat pump, and the payback period on the install cost. You enter your heating use, power price and the install cost, and it shows the annual saving and how long the heat pump takes to pay for itself.
Assumes you currently use plug-in electric heating (one unit of power per unit of heat). The heat pump delivers the same heat using less power, by its coefficient of performance. Real efficiency varies with temperature. Power prices change, so use your current rate. Estimate only.
The calculator works out the heat you need over the season, then the cost of delivering it with plug-in electric heating, which uses one unit of power per unit of heat. The heat pump delivers the same heat using less power, dividing by its coefficient of performance. The difference is your annual saving, and dividing the install cost by that saving gives the payback period.
Delivering 18 kWh of heat a day for 150 days at 28 cents costs about $756 with plug-in heaters. A heat pump with a COP of 3.5 delivers the same heat for around $216, a saving of about $540 a year. A $3,000 install pays back in roughly 5 to 6 years.
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