Compare Water Heating Costs

This calculator shows the approximate costs of heating water for a typical family. Gallons-per-day, temperature rise, cost-per-unit, and energy factor values are all adjustable. This calculator is for comparison purposes only. Actual performance may vary. Default energy prices last updated: December 2023.

Gal/Day: Temperature Rise °F:
Energy Unit Cost/Unit Energy Factor Annual Cost 10-yr Cost
Heat pump water heater kWh $ $ $
Assumptions: BTU/Unit Gal/Day Temp Rise
3412
Oil boiler w/indirect tank gal $ $ $
Assumptions: BTU/Unit Gal/Day Temp Rise
139000
Natural gas instantaneous therm $ $ $
Assumptions: BTU/Unit Gal/Day Temp Rise
100000
Oil boiler w/tankless coil gal $ $ $
Assumptions: BTU/Unit Gal/Day Temp Rise
139000
Natural gas storage tank therm $ $ $
Assumptions: BTU/Unit Gal/Day Temp Rise
100000
Propane (LP) instantaneous gal $ $ $
Assumptions: BTU/Unit Gal/Day Temp Rise
91500
Propane (LP) storage tank gal $ $ $
Assumptions: BTU/Unit Gal/Day Temp Rise
91500
Electric tank kWh $ $ $
Assumptions: BTU/Unit Gal/Day Temp Rise
3412

kWh (Kilowatt hour) - A unit of electricity.
therm - A measure of natural gas heat energy equal to 100,000 BTUs.
LP (liquefied petroleum) - Liquefied petroleum gas. Also referred to as propane or butane gas.
Energy Factor - A measure of efficiency. An energy factor of 0.50 is 50% efficient.
Temperature Rise - The temperature difference between the cold and hot water. Typical incoming water is 50°F and is generally heated to 120°F, so the typical temperature rise is 70°F.
Gal/Day - Gallons per day of hot water used. A typical family uses 50 gallons per day.
Gal - Gallon.