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.

Click here for energy cost assumptions.

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


This calculator is for comparison purposes only. Actual performance may vary. Default energy prices last updated: 01/03/2021.

  1. Natural gas price is a weighted average residential heating price of each natural gas utility in Maine. The following are prices for each utility: $2.064 Maine Natural Gas, $1.630 Bangor Natural Gas, $1.756 Unitil Maine, $2.059 Summit Natural Gas.