How to Calculate Heat Pump vs Furnace Operating Costs
Standard fossil fuel furnaces burn fuel to generate heat at 80% to 96% efficiency (AFUE rating). In contrast, electric heat pumps do not generate heat—they transfer ambient heat from outdoor air into your living space at 250% to 380% thermodynamic efficiency (COP 2.5–3.8).
Heat Pump vs Combustion Operating Cost Formula
Heat Pump Operating Cost ($ / yr)
Annual Cost=
Annual MMBtu × 293.07 kWh/MMBtuHeat Pump COP
×Electric Rate ($/kWh)Furnace Operating Cost ($ / yr)
Annual Cost=
Annual MMBtuFurnace AFUE %
×Fuel Price ($ / MMBtu)Step-by-Step Calculation Breakdown (Cold-Climate Example)
Step 1: Baseline Home Parameters
Annual heating load: 60 MMBtu. Existing 80% AFUE natural gas furnace at $1.40/therm ($14.00/MMBtu). New heat pump COP: 3.2 with electric rate at $0.16/kWh.
Step 2: Operating Expense Derivation
Gas Furnace: (60 ÷ 0.80) × $14.00 = $1,050 / year
Heat Pump: [(60 × 293.07) ÷ 3.2] × $0.16 = $879 / year
Step 3: Annual Dollar Savings & Payback
Net Annual Savings=$1,050 − $879=+$171 / year
Fuel Cost & Efficiency Benchmark Comparison
| Heating Technology | Standard Fuel Price | Efficiency Rating | Cost per Delivered MMBtu |
|---|---|---|---|
| Cold Climate Heat Pump | $0.16 / kWh | 320% (3.2 COP) | $14.65 / MMBtu |
| Standard Natural Gas (90% AFUE) | $1.40 / therm | 90% AFUE | $15.55 / MMBtu |
| Heating Oil Furnace (80% AFUE) | $3.85 / gallon | 80% AFUE | $34.75 / MMBtu |
| Propane Furnace (80% AFUE) | $3.20 / gallon | 80% AFUE | $43.72 / MMBtu |