Whole-House Dehumidifier Energy Payback Calculator

Calculate how much energy a whole-house dehumidifier saves by reducing HVAC runtime and whether the upgrade pays back. Enter annual HVAC runtime, expected runtime reduction, your electric rate, and installed cost. Optionally adjust HVAC and dehumidifier power draws to reflect your equipment mix and see net kWh savings, annual dollar savings, and simple payback.

Estimated hours your HVAC system operates each year.
Percent of HVAC runtime you expect the dehumidifier to eliminate.
All-in electricity cost per kilowatt-hour.
Total cost including equipment, installation, and permits.
Defaults to 3.5 kW if blank. Override with your system's average draw.
Defaults to 0.7 kW when left blank.

Model assumes steady power draws and runtime reductions. Verify equipment specifications and consult HVAC professionals before purchasing.

Examples

  • 1,500 hours, 22% reduction, $0.18/kWh, $3,200 cost, 9.0 kW HVAC, 0.6 kW dehumidifier ⇒ Net savings are 2,772.00 kWh, worth $498.96 annually, yielding a 6.41-year payback.
  • 900 hours, 10% reduction, $0.12/kWh, $2,900 cost, defaults for power draws ⇒ Only 477.00 kWh are saved for $57.24 per year, stretching payback to 50.66 years.

FAQ

How do utility rebates factor in?

Subtract rebates from the installed cost before running the calculation to shorten the payback timeline.

What if the dehumidifier increases HVAC efficiency?

Reduce the HVAC power draw input to model improved coil performance or use a higher runtime reduction percentage if humidity control allows higher thermostat setpoints.

Can I model seasonal differences?

Run the calculator for summer and shoulder seasons separately, then add the savings to approximate a full-year impact.

Additional Information

  • HVAC and dehumidifier draws represent average power while the equipment is running; adjust to match manufacturer specs.
  • Runtime reduction percentage converts to hours avoided and multiplies by HVAC load to estimate energy saved.
  • The dehumidifier's own consumption is subtracted so savings represent net impact on the utility bill.
  • Simple payback divides installed cost by annual savings and does not account for rebates or maintenance costs.

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