Heat Pump vs Furnace Savings Calculator
Enter your home's annual heating energy, the heat pump's seasonal efficiency (COP), your electricity rate, and the efficiency of the system you are comparing against, and this calculator estimates each system's yearly running cost, the annual savings, and how long the price difference takes to pay back. It is a screening estimate, not an engineering load calculation.
Heating & systems
Comparison COP 1.0 = electric resistance heating.
Annual savings
$2,266.67
heat pump $1,133.33/yr vs comparison $3,400.00/yr
Payback
1.76 yrs
Heat pump kWh/yr
6,667
System comparison
Annual running cost
How it works
A heat pump does not create heat — it moves it, which is why it can deliver more heat energy than the electricity it consumes. Its coefficient of performance (COP) is that ratio: a COP of 3 means 3 units of heat per 1 unit of electricity. So the electricity a heat pump needs equals your heating demand divided by its COP. For 20,000 kWh of annual heat at a COP of 3, the heat pump draws about 6,667 kWh of electricity. Electric resistance heating (baseboards, furnaces with heating elements) has an effective COP of 1 — every kilowatt-hour of electricity becomes one kilowatt-hour of heat, with no multiplication.
Running cost is electricity consumed multiplied by your rate. Continuing the example at $0.15 per kWh, the heat pump costs about $1,000 a year to run while electric resistance costs $3,000 — a $2,000 annual saving. If a heat pump installation costs more upfront than the alternative, the calculator divides that price difference by the annual saving to give a simple payback in years. The US average residential electricity rate is around 18.8 cents per kWh as of 2026 (EIA), but yours may differ substantially by state.
The comparison COP field lets you model different baselines. Use 1.0 for electric resistance. To approximate a gas furnace you would convert its fuel cost to an equivalent — but because gas prices, furnace efficiency, and fuel units vary widely, this tool focuses on the electric-to-electric comparison where the COP method is exact. The biggest real-world caveat is that a heat pump's rated COP falls as outdoor temperatures drop; the seasonal average (sometimes expressed as HSPF) is lower than the lab rating, so use a realistic seasonal COP for your climate rather than the nameplate peak.
Frequently asked questions
What COP should I use for my heat pump?+
Use a seasonal average appropriate to your climate, not the peak lab rating. Modern cold-climate heat pumps often deliver a seasonal COP around 2.5–3.5, but efficiency drops as it gets colder because the unit works harder to extract heat from frigid air. Manufacturers publish an HSPF (Heating Seasonal Performance Factor) rating, which can be roughly converted to a seasonal COP by dividing HSPF by about 3.41. In very cold weather many systems fall back on auxiliary resistance heat, which lowers the effective seasonal COP further. When unsure, run the calculator with a conservative COP (say 2.5) and an optimistic one (3.5) to bracket your likely savings.
How do I estimate my annual heating energy need?+
The most reliable way is from past usage: if you currently heat with electric resistance, your winter electricity bills above your summer baseline approximate your heating kWh directly. For gas heating, convert your annual therms or cubic feet to kWh (1 therm ≈ 29.3 kWh of heat, adjusted for furnace efficiency of roughly 80–95%). A rough rule of thumb for a typical US home is 10,000–25,000 kWh of heat per year depending on size, insulation, and climate, but this varies enormously. A professional Manual J load calculation gives the accurate figure a contractor would size equipment to.
Why doesn't this include a gas furnace comparison directly?+
Because comparing electricity to gas honestly requires several extra variables — the gas price per therm in your area, your furnace's efficiency (AFUE), and the unit conversion between therms and kWh — and small errors in any of them swing the result. Rather than bury those assumptions, this calculator does the electric-to-electric comparison precisely (heat pump vs electric resistance), where the COP method needs no fuel conversion. If you heat with gas, compare your actual annual gas heating cost against the heat pump running cost this tool computes, using your real gas bill for the baseline.