Heat Pump Savings Calculator
A heat pump usually heats a home for less than gas, oil or electric resistance because it moves several units of heat per unit of electricity. Enter your annual heat demand, your current system’s efficiency and fuel price, the heat pump’s SCOP and your electricity rate to see your annual running-cost saving, optional payback and the CO₂ you’d cut each year.
Using US averages. Set your state or ZIP for local electricity, fuel, sun and grid figures. Stays on your device.
Useful heat delivered per year. A typical home is ~8,000–18,000 kWh.
Gas furnace ~90%, old boiler ~80%, electric resistance 100%.
Per kWh of fuel energy (gas is sold per therm — convert).
Seasonal heat out per unit of electricity. Typical 2.5–4.0.
Assumptions
Heat pump cost after grants/incentives, minus what you'd spend on the alternative. Enables payback.
Natural gas ≈ 0.18 kg CO₂/kWh of fuel; heating oil is higher.
Estimated annual saving
$29
Running cost only — the heat pump is cheaper to run with these inputs.
Verdict: A heat pump saves about $29 a year versus your current heating, and cuts about 0.9 t of CO₂.
Get a shareable image- Current heating cost
- $667per year
- Heat pump cost
- $638per year
- CO₂ saved / year
- 0.94 t
- Payback
- Add install cost
- Heat pump electricity
- 3,750 kWhper year
- Current heating$667
- Heat pump$638
Running cost and CO₂ only — excludes maintenance and any backup resistance heat. Estimate only; not financial advice.
Save & compare
Save the current inputs and compare up to 4 side by side. Stored on this device only.
How it works
This calculator compares the cost to run a heat pump against your current heating system, sized so both deliver the same useful heat each year.
- Annual heat demand is the heat your home actually needs — both systems must supply it.
- Current efficiency sets how much fuel your existing system burns; below 100% it wastes energy up the flue.
- Heat pump SCOP sets how little electricity the heat pump draws — above 1, it delivers more heat than it consumes.
- Prices turn fuel and electricity into dollars, and emission factors turn them into CO₂.
The headline is your annual running-cost saving. The bars compare each system’s yearly cost, and adding a net install cost reveals a simple payback.
Methodology & assumptions
Results use the inputs you provide plus these representative defaults. Every one is editable in the calculator and tied to a dated source. Maintenance and any backup resistance heat are excluded.
| Assumption | Default | Source |
|---|---|---|
| Heat pump SCOP (default)Seasonal coefficient of performance; editable, typical 2.5–4.0. | 3.2 | U.S. Department of Energy (energy.gov) |
| Current fuel price (default)Per kWh of fuel energy, converted from $/therm. | $0.05 /kWh | U.S. Energy Information Administration (EIA) |
| Current fuel emissions (default)Natural gas combustion per kWh of fuel; oil is higher. | 0.18 kg CO₂/kWh | U.S. Environmental Protection Agency (EPA) |
| Electricity price | $0.17 /kWh | U.S. Energy Information Administration (EIA) |
| Grid carbon intensity | 0.39 kg CO₂/kWh | U.S. Environmental Protection Agency (EPA), eGRID |
Full formula, every default and its source: Heat pump savings methodology.
Worked example
Take a home needing 12,000 kWh of heat a year, today from a 90%-efficient gas system at $0.05/kWh of fuel, replaced by a heat pump with a SCOP of 3.2 on $0.17/kWh electricity:
- Current heating: 12,000 ÷ 0.90 × $0.05 ≈ $667/year.
- Heat pump electricity: 12,000 ÷ 3.2 = 3,750 kWh → 3,750 × $0.17 = $637.50/year.
- Annual saving ≈ $29 — modest here, because cheap gas competes closely with this electricity price.
- CO₂: (13,333 kWh × 0.18) − (3,750 kWh × 0.39) = 2,400 − 1,462.5 ≈ 0.94 tonnes saved per year.
The carbon win is clear even when the cash saving is small. Cheaper electricity (for example from solar) or a higher gas price would widen the saving sharply — put in your own numbers above.
Frequently asked questions
Is a heat pump cheaper to run than a gas boiler or furnace?
Often, but not always. A heat pump delivers several units of heat per unit of electricity (its SCOP), while gas burns more fuel than the heat it delivers. Whether it wins depends on your electricity price versus your gas price: cheap gas and expensive electricity can close or reverse the gap. Enter your own prices to see your result.
What is SCOP (or COP)?
COP is the coefficient of performance — heat delivered divided by electricity consumed at a single condition. SCOP is the seasonal average across a heating season, so it accounts for milder and colder days. A SCOP of 3.2 means the heat pump delivers 3.2 kWh of heat for every 1 kWh of electricity it uses.
Do heat pumps work in cold climates?
Yes — modern cold-climate models heat homes well below freezing. But efficiency falls as it gets colder, so the seasonal SCOP in a harsh climate is lower than in a mild one, and many systems use backup resistance heat on the coldest days. If you live somewhere cold, use a lower SCOP to stay realistic.
How do electricity and fuel prices change the answer?
They are the biggest lever. The heat pump’s cost scales with your electricity price; the current system’s cost scales with your fuel price. A high electricity-to-gas price ratio shrinks the saving, while cheap electricity (or a solar array) widens it. Always replace the defaults with your own rates.
How is the CO₂ saving calculated?
We multiply the fuel your current system burns by its emission factor (0.18 kg CO₂/kWh for natural gas by default), and the heat pump’s electricity by your grid’s carbon intensity (0.39 kg CO₂/kWh US average). The difference is your annual CO₂ saving. A cleaner grid increases it.
How does payback work with an install cost?
Enter the net install cost — the heat pump price after any grants, minus what you would otherwise spend on the alternative system. We divide it by the annual running-cost saving. If the heat pump costs more to run, it never pays back on running cost alone and we say so rather than show a misleading number.
What is annual heat demand and how do I estimate it?
It is the useful heat your home needs per year, in kWh. A quick estimate: take your annual gas use in kWh and multiply by your boiler efficiency (e.g. 0.9). Many homes land between 8,000 and 18,000 kWh depending on size, insulation and climate.
Related calculators
Related guides
- Heat pump vs gas furnace: running costs comparedHeat pump vs gas furnace running cost, decoded — how a heat pump SCOP of 3.2 beats a 90% furnace, when cheap gas wins, plus upfront cost and payback.
- What uses the most electricity in your home?The biggest electricity users in a typical home are heating, cooling and water heating — here is how to rank your own loads and cut the costliest ones.
By EnergyTally Team · Editorial & analysis team
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- EnergyTally Team,