Delivered Heating Cost per MMBTU by Fuel
Type in the prices you actually pay for electricity, gas, propane and oil, plus the heat-pump COP and combustion efficiency. The tool ranks every fuel by delivered $/MMBTU so you can see the cheapest way to heat — on your rates, in your units.
Calculator
On your prices, Heat pump delivers the cheapest heat at $14.65/MMBTU. Ranking uses stable energy contents and the efficiencies you enter.
Fuels are sold in units that hide how much heat you actually get: a therm of gas, a gallon of propane, a gallon of oil and a kilowatt-hour of electricity all deliver wildly different amounts of energy, and each appliance wastes a different share. The honest apples-to-apples number is the cost to deliver one million BTU (MMBTU) of heat into the house. This tool computes that figure for five heat sources at once — electric resistance, a heat pump, natural gas, propane and heating oil — and ranks them cheapest to most expensive on the prices you enter. Because every price is yours and every energy content is a fixed physical constant, the ranking stays correct no matter what the market does.
Formula
Each fuel uses the same delivered-cost formula:
$/MMBTU = price ÷ (energy content × efficiency) × 1,000,000
with these stable energy contents and efficiencies:
- Electric resistance: 3,412 BTU/kWh × efficiency 1.0
- Heat pump: 3,412 BTU/kWh × your COP (an electric "efficiency" above 1)
- Natural gas: 100,000 BTU/therm × your AFUE
- Propane: 91,500 BTU/gallon × your AFUE
- Heating oil: 138,500 BTU/gallon × your AFUE
The lowest delivered $/MMBTU is the cheapest heat.
Worked example
Using the defaults — electricity $0.15/kWh, heat-pump COP 3, gas $1.50/therm, 95% AFUE, propane $2.50/gal, oil $3.00/gal — the ranking works out to:
- Heat pump: 0.15 ÷ (3,412 × 3) × 1e6 = $14.66/MMBTU (cheapest)
- Natural gas: 1.50 ÷ (100,000 × 0.95) × 1e6 = $15.79/MMBTU
- Heating oil: 3.00 ÷ (138,500 × 0.95) × 1e6 = $22.80/MMBTU
- Propane: 2.50 ÷ (91,500 × 0.95) × 1e6 = $28.76/MMBTU
- Electric resistance: 0.15 ÷ (3,412 × 1) × 1e6 = $43.96/MMBTU (most expensive)
At these prices the heat pump edges out gas, oil sits in the middle, propane is dear and plain electric-resistance heat costs about three times a heat pump — the classic reason electric baseboard is expensive to run.
Reading the ranking honestly
Propane and oil are priced per gallon, so their delivered cost swings hard with the per-gallon price you enter — check a recent delivery ticket. The single AFUE field is applied to all three combustion fuels for simplicity; if your gas, propane and oil appliances have very different efficiencies, run the tool once per fuel with each true AFUE. Electric resistance is pinned at an efficiency of 1.0 (every kWh becomes heat) and the heat pump uses your COP, which is why the same electricity price produces two very different lines.
This ranks running cost only. It ignores the up-front cost of switching fuels, whether a gas or propane line even reaches your house, storage tanks, and the heat pump's bonus of also providing summer cooling. Treat the output as a planning estimate and confirm your true seasonal COP, since a heat pump's advantage narrows on the coldest days.