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UNITED STATES · EFFICIENCY & BILLS

Heat pump vs. gas furnace: compare the cost of delivered heat

By SAVPWR Editorial · Published · 2 min read

For U.S. residential systems. General education, not a site diagnosis or engineering certification.

THE DIRECT ANSWER

How can I compare electricity and gas prices fairly?

Convert both fuels into a cost per delivered unit of heat. Electricity price alone cannot be compared with a price per therm. State the assumed heat-pump COP and furnace efficiency, then test how the result changes.

Use consistent units

For an illustrative comparison, one therm contains 100,000 Btu and one kWh is about 3,412 Btu. Delivered heat from the furnace depends on the efficiency assumption; delivered heat from the heat pump depends on COP under the relevant conditions. Equipment selection still requires heating-capacity data. [1]

Do not omit the second heat source

A heat pump with electric resistance backup can have a different seasonal cost from a compressor-only estimate. For dual fuel, ask how changeover is controlled and which source operates at different temperatures. Maintenance and a gas customer charge may remain if other gas appliances stay. [1][2]

Compare avoidable costs

Use energy charges that change with consumption. Identify fixed charges separately, and include them only when the project would actually remove them. Time-varying electricity tariffs require a time-specific comparison instead of one blended price. [2]

PUT IT TO WORK

Decision exercise

Assume electricity $0.24/kWh, COP 3, gas $1.80/therm and furnace efficiency 0.90. Heat pump: 293.1 × 0.24 / 3 = $23.45 per million Btu delivered. Gas: 10 × 1.80 / 0.90 = $20.00. Under these assumptions gas has the lower energy cost; changing prices or COP changes the result.

Any numbers in this exercise are illustrative assumptions, not product performance, an installed quote or a personal savings estimate.

What to bring to the conversation

  • Get current utility tariffs rather than a state average.
  • Test several COP assumptions and backup scenarios.
  • Keep fixed charges, maintenance and capital cost separate.

One more useful distinction

Are heat pumps always cheaper to operate?

No. Relative energy prices, actual operating performance, backup use and building loads determine the result.

Sources and verification

Technical statements draw on the linked references. Decision exercises and comparison frameworks are SAVPWR’s own explanatory examples. Current rules and program availability should be rechecked before a purchase.

  1. PNNL — Cold Climate Heat Pump Sizing and SelectionSource checked 2026-11-09 · External primary reference
  2. U.S. EIA — Electricity Prices and Factors Affecting PricesSource checked 2026-11-09 · External primary reference

AI-assisted preparation; checked against public sources. These articles have not received a licensed HVAC professional’s review. Read our editorial policy.

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