All high-efficiency appliances presented in the calculator qualify for Intermountain Gas Energy Efficiency Rebates. See a complete list of residential rebates here. Get cash back now when you install high-efficiency natural gas appliances and save on your monthly bills tomorrow!
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Savings Calculator Instructions

?Water Heater Calculator:
  • Select the number of people in your household.
  • Select the type of current equipment.
  • Select the efficiency, or Uniform Energy Factor (UEF), of your current water heater. The UEF is typically found on the specification sheet provided with your water heater. If you don’t know the UEF of your water heater, select “Standard” to compare all high-efficiency options. “Standard” represents the current minimum efficiency allowed by code.
Furnace Calculator:
  • Select the Capacity of your current furnace. If you don’t know the capacity of your furnace, for estimating purposes, you can use 50 BTU per square foot.
    (For example: 2,000 square foot home * 50 BTU = 100,000 BTU furnace)
  • Select the efficiency, or AFUE (Annual Fuel Utilization Efficiency), of your current furnace. The capacity and AFUE is typically presented on a sticker on the furnace. If you don’t know the AFUE of your current equipment, select “Standard” to compare all high-efficiency options. “Standard” represents common efficiency of standard equipment.


This calculator tool is intended to be used solely as a general guide for an estimate of potential cost savings. The results should be used as an indication only and may differ from reality. Many factors may influence the results of energy efficiency measures, including, but not limited to, individual behavior, the weather, and the condition of the building in which the equipment is installed. Intermountain Gas Company does not guarantee or warrant the accuracy of the cost savings estimated by this calculator.