Water Heater Energy Factor Calculator

At the bottom of the calculator are more settings you can adjust for further accuracy such as the cold water intake temperature the water heater temperature and the cost of electricity.

Water heater energy factor calculator.

Hi larry the energy that is used to heat water from 40 degrees to 60 is the same amount that is lost when the water cools down from 60 to 40 only changed sign. Start temp as final and end temp as start. Energy factor 0 92 electric 0 61 gas energy cost 0 06 per kwh 60 per therm. Expressed as a decimal the uniform energy factor is determined by running a department of energy specified simulated use test sut.

Quantity of water heaters to be purchased unit s 1 unit see assumptions for various daily water use totals. The uniform energy factor for residential and certain commercial water heaters refers to its efficiency when run under standardized conditions for a 24 hour period. Using the doe test procedure for calculations a fifty gallon electric resistance storage water heater with an energy factor of 0 95 would consume 4 622 kilowatt hours per year see table 1 on page nine for figures. The comparison assumes a storage tank water heater as the input type.

The term is used by the united states department of energy to develop and enforce minimum energy conservation standards under. Antonio january 5 2019. The higher the energy factor of a water heater the more efficient it is. Next you can adjust your current water heater s energy factor as well as the energy factor of your new water heater.

The energy factor is based on the amount of hot water produced per unit of fuel consumed per day. The energy factor ef indicates a water heater s overall energy efficiency based on the amount of hot water produced per unit of fuel consumed over a typical day. Use the energy factor to determine the energy efficiency of a storage tankless or demand type water heater or heat pump water heater. A water heater s energy factor ef is a measure of useful energy coming out of the water heater divided by the amount of energy going in.

To calculate a water heater s energy factor you take the amount of energy the water heater puts to use and divide it by the total amount of energy that goes into powering the unit. Electric water heaters typically have energy factors between 0 75 and 0 95. The energy factor is currently used for rating the efficiency of water heaters dishwashers clothes washers and clothes dryers. An energy factor is a metric used in the united states to compare the energy conversion efficiency of residential appliances and equipment.

The water heaters themselves haven t changed but the way we calculate the ratings and other facts and figures associated with them is different.