Heat Pump vs. Furnace Cost Calculator
Compare the cost of delivered heat from a heat pump with natural gas, propane, heating oil, or electric resistance heat. Enter your own utility and fuel prices so the result reflects your bills instead of a generic national average.
The calculator can show cost per million BTU of heat delivered to the home, an optional annual cost comparison based on your heating-only fuel use, and the electricity price at which the heat pump and your current system would cost about the same to operate.
Compare Heating Operating Cost
How the Heat Pump vs. Furnace Calculator Works
The calculator converts every heating source into the same output unit: cost per million BTU (MMBtu) of heat actually delivered to the home. That makes it possible to compare fuels with very different billing units.
For furnaces, the calculation applies the AFUE you enter. ENERGY STAR defines AFUE as the percentage of incoming fuel energy converted to useful space heat rather than lost. For the heat pump, the calculator uses HSPF2, which ENERGY STAR defines as seasonal space heating delivered in BTU divided by total heat-pump electricity use in watt-hours.
Fuel Energy Values Used
The calculator uses current U.S. Energy Information Administration conversion values to put fuels on a common energy basis.
| Energy source | Energy content used |
|---|---|
| Electricity | 3,412 BTU per kWh |
| Natural gas | 100,000 BTU per therm |
| Propane | 91,452 BTU per gallon |
| Heating oil | 137,381 BTU per gallon |
Fuel heat content can vary slightly, and EIA periodically updates conversion factors. The values above are suitable for comparison but are not a substitute for utility-specific billing information.
Why Enter Your Own Energy Prices?
A heat pump can be less expensive to operate than one fuel in one utility territory and more expensive than another fuel somewhere else. Electricity, gas, propane, and oil prices change over time and vary by supplier, so your own bill is more useful than a national average.
For natural gas, use the effective commodity/delivery price per therm if you can identify it. Fixed customer charges should usually be excluded from the variable operating-cost comparison unless switching systems would actually eliminate that charge.
What Does HSPF2 Mean?
HSPF2 is the standardized seasonal heating-performance rating used for heat pumps. It expresses seasonal heating delivered in BTU for each watt-hour of electricity consumed under the test procedure. Higher HSPF2 generally means lower electricity use for the same standardized seasonal heating load.
ENERGY STAR’s current heat-pump criteria set minimum HSPF2 levels for qualifying equipment and additional low-temperature requirements for cold-climate models. The actual model rating should be used in this calculator when possible.
Heat Pump vs. Natural Gas Furnace
Natural gas and heat pumps can both have low operating costs, so the result often depends heavily on the local gas rate, electric rate, furnace AFUE, and heat-pump seasonal performance. The calculator’s break-even electricity price is especially useful here: it shows the approximate electricity rate at which the two systems have equal calculated variable cost per delivered MMBtu.
Heat Pump vs. Propane Furnace
Propane is sold by the gallon and has a different heat content from natural gas. Rural homeowners who buy propane can enter their actual delivered propane price to compare it directly with a proposed heat pump.
Heat Pump vs. Oil Furnace
Heating oil is also sold by the gallon. The calculator applies the oil furnace efficiency you enter before comparing the cost of useful heat with the heat pump.
Dual-Fuel Heat Pump + Furnace Comparison
If you plan to keep a furnace as backup, reduce the heat-pump share below 100%. The calculator then estimates a blended seasonal operating cost using the heat pump for part of the annual space-heating load and the current system for the remainder.
This is a simplified seasonal comparison. A real dual-fuel control strategy depends on outdoor temperature, equipment capacity, utility prices, thermostat logic, and the chosen switchover or balance point.
What This Calculator Does Not Include
- Installation or replacement cost
- Financing cost
- Cooling-season savings
- Fixed monthly utility/customer charges
- Duct losses that differ between the old and new systems
- Furnace blower electricity
- Maintenance or repair costs
- Demand charges or time-of-use pricing
- Exact hour-by-hour cold-weather heat-pump performance
- Rebates and incentives
For upfront project budgeting, use the Heat Pump Cost Calculator. For current incentive information, see Heat Pump Rebates & Incentives.
Heat Pump vs. Furnace Cost FAQs
Is a heat pump cheaper to run than a gas furnace?
Sometimes, but not always. The answer depends on electricity price, gas price, furnace AFUE, heat-pump seasonal efficiency, climate, and backup-heat use. Enter your own rates rather than relying on a universal answer.
Is a heat pump cheaper to run than propane?
It can be, particularly where delivered propane is expensive relative to electricity, but the result depends on the prices and equipment efficiencies you enter.
Why does the calculator ask for annual fuel use?
Annual use is optional. If you provide heating-only usage, the calculator can estimate the current annual space-heating cost and compare it with the heat-pump or dual-fuel strategy. If your gas also serves water heating or cooking, subtract those uses when possible.
Does HSPF2 predict my exact Iowa winter electricity use?
No. HSPF2 is a standardized seasonal rating. Actual performance depends on weather, thermostat settings, system sizing, ductwork, defrost, backup heat, and the heat pump’s capacity and efficiency at specific outdoor temperatures.
Methodology & Sources
The tool uses EIA fuel heat-content conversions, the AFUE entered by the user, and HSPF2 entered for the proposed heat pump. The annual comparison assumes that the current heating-only fuel use represents the same useful space-heating demand that the new system would need to provide. That is a simplification, so actual bills may differ.
- U.S. EIA: Energy units and fuel conversion factors
- U.S. EIA: 2026 energy conversion calculators
- ENERGY STAR: AFUE definition
- ENERGY STAR: HSPF2 and cold-climate heat-pump criteria
Considering a Heat Pump in Eldora, IA?
Use the operating-cost calculator to compare energy costs, then compare actual installation scope and equipment. If you are considering a heat pump, dual-fuel system, or furnace replacement in Eldora or the surrounding area, submit your project details for a local service request.