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🌡️ Climate Control

How Many kWh Does a Whole House Fan Use?

Whole House Fan energy cost calculator — see your exact daily, monthly, and yearly electricity cost.

Rate — APRIL 2026 ⚡ 300W typical
1Enter Wattage
2Set Hours
3See Costs
$

US national average. Edit for your local rate.

Daily Energy Use

1.20

kWh / day

Monthly Cost

$6.78

Yearly Cost

$82.48

Whole House Fan — Cost Breakdown

Period kWh Used Cost ($)
Per Hour 0.3000 $0.0565
Per Day 1.20 $0.23
Per Month (30 days) 36.00 $6.78
Per Year (365 days) 438.00 $82.48
Real-World Comparison

Running a whole house fan for 4 hours uses only about a tenth of the energy a central AC uses in the same time.

3 Ways to Cut Your Whole House Fan Energy Bill

  • 🌱

    Open windows on the windward side of the house before turning on the fan to maximize cross-ventilation.

  • 💡

    Run it in the evening and early morning when outdoor air is coolest for maximum cooling benefit.

  • Install an insulated cover over the fan louvers in winter to prevent heat loss through the attic opening.

Startup Surge Information

The large motor draws a startup surge of roughly 600–900W for a few seconds before settling to its running wattage.