Heat Pump vs Boiler Cost Calculator

How the heat pump vs boiler cost calculator works

Heat-pump electric input = useful heat ÷ seasonal COP. Boiler fuel input = the same useful heat ÷ boiler efficiency fraction. Both denominators must be positive. Seasonal COP is an output/input energy ratio in matching units, not a percentage or a single-condition rating assumed valid for every season.

Each scenario extends unrounded input energy at its entered energy rate and rounds that charge half-up to cents. Add its separately rounded fixed operating cost. Heat-pump saving is rounded boiler cost minus rounded heat-pump cost; negative saving favors the boiler scenario. The winner uses those displayed rounded totals.

Fixed costs remain at zero heat demand. This does not size equipment, estimate a building heating load, guarantee comfort or forecast seasonal performance. Backup heat, defrost, auxiliary electricity, distribution losses and demand charges must be included in compatible performance/rate inputs or addressed separately. Capital costs, rebates, finance and emissions are excluded. DOE defines COP and annual fuel utilization efficiency; no purchasing standard is applied by this comparison.

Worked example

20,000 kWh useful heat at seasonal COP 3 requires about 6,666.667 kWh electricity. At 0.20/kWh plus 200 fixed cost, the heat-pump scenario costs 1,533.33. At 90% boiler efficiency, fuel input is about 22,222.222 kWh; at 0.08/kWh plus 150 fixed cost, it costs 1,927.78. The heat-pump scenario is 394.45 lower. COP 2 instead makes it 2,200, which is 272.22 higher than the boiler.

Sources and assumptions

The source material explains the underlying calculation or pricing structure. Entered prices, costs, schedules and scenario choices are your assumptions; this tool does not obtain supplier quotes or predict actual results.

• U.S. DOE: boiler energy efficiency and energy-cost calculations
• U.S. DOE: definitions of COP and annual fuel utilization efficiency