Water Heating Spreadsheet

Water heating is a major energy consumer. Although the energy consumed daily is often less than for Air Conditioning or Heating, it is required year round, making it a good application of solar energy.

Use this spreadsheet to explore the energy usage of your water heater, and to estimate whether a solar water heater could save you money.

Water Heater Characteristics
Diameter (feet) Water Inlet Temperature (Degrees F)
Capacity (gallons) Ambient Temperature (Degrees F)
Surface Area (calculated - sq ft) Hot Water Temperature (Degrees F)
Effective R-value Hot Water Usage (Gallons per Day)
Energy Use
Heat Delivered in Hot Water (BTUH)
Heat loss through insulation (BTUH)
Overall Efficiency
Conversion Efficiency 0.98
BTUH Power Into Water Heater BTUH
$/Therm Utility Rates $/KwH
$ Yearly Water Heating Cost $
Solar Water Heater Cost: $ Percentage Solar:
years Payback Time for Solar System years

This Calculator Supplied courtesy of Chuck Wright Consulting, Technology Serving Sustainability

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