This guide is educational. Local design conditions, codes, utility tariffs, manufacturer instructions, and site measurements control a real project.
Start with delivered heat
Comparing a dollar per kWh with a dollar per therm is misleading. Convert both systems to the cost of useful heat delivered indoors. A heat pump’s seasonal COP and a furnace’s seasonal efficiency translate purchased energy into delivered energy.
Cold-weather performance needs documentation
Heat-pump output and efficiency change with outdoor temperature. Review manufacturer performance tables or certified data at the local winter design temperature. The design should explain the balance point, auxiliary heat, defrost behavior, and whether existing electrical service can support the system.
Include project and utility structure
Fuel savings are only one row. Add installed cost, electrical upgrades, gas-line or vent changes, maintenance, equipment life assumptions, incentives, financing, and fixed monthly utility charges. Removing an entire gas service may save a fixed charge; keeping it for other appliances may not.
Model scenarios instead of one forecast
Test a cold-year COP, an average-year COP, and more than one utility-rate case. Scenario ranges expose which assumptions control the decision and make a proposal easier to challenge.
Turn the guide into numbers with our free HVAC calculators, then compare the result with itemized local bids.