How much does it cost to run a dehumidifier?
At the 785 W nameplate figure, a dehumidifier running 12 hours a day uses 9.42 kWh — $1.60 a day and about $48.71 a month at 17¢ per kWh.
How to work it out
- 785 W ÷ 1,000 = 0.785 kW × $0.17/kWh = $0.13 an hour
- 0.785 kW × 12 h = 9.42 kWh × $0.17 = $1.60 a day
- 9.42 kWh × 365 days = 3,438 kWh a year = $584.51 ($48.71 a month)
Virginia Cooperative Extension’s nameplate list gives 785 W for a dehumidifier. Smaller and newer units often draw less, so read the label — and like an AC, a dehumidifier’s compressor cycles off once it reaches the humidity you set.
Adjust for your project
More options: Days/yr
- Cost per hour
- $0.13
- Cost per month (average)
- $48.71
- Cost per year
- $584.51
- Energy per day
- 9.42 kWh
- Energy per year
- 3,438 kWh
The same appliance at other hours per day
| Hours used per day | Energy per day | Cost per day | Cost per month (average) |
|---|---|---|---|
| 1 | 0.79 kWh | $0.13 | $4.06 |
| 2 | 1.57 kWh | $0.27 | $8.12 |
| 4 | 3.14 kWh | $0.53 | $16.24 |
| 8 | 6.28 kWh | $1.07 | $32.47 |
| 12 | 9.42 kWh | $1.60 | $48.71 |
| 24 | 18.84 kWh | $3.20 | $97.42 |
What to know about dehumidifier running costs
- The humidistat sets the hours. In a damp basement in July it may run most of the day; in a dry spell, a few hours. Twelve hours is a middle-of-the-summer assumption.
- Set it to the humidity you need. Each step drier means longer compressor runs. Many people aim for the range their unit marks as comfortable rather than the lowest setting.
- Drain it continuously. A full bucket stops the unit; a hose to a floor drain keeps it working without more energy per hour.
- Basement temperature matters. A compressor dehumidifier can struggle in a cold space, which may mean long run times for little water removed — check the operating range in the manual.
Want to run one from solar in a cabin or boat? Enter its watts and hours in the solar load calculator and carry the total into the solar panel calculator. The same arithmetic for a summer cooling load is on the cost to run a window AC unit.
Different size? Use the full Electricity Cost Calculator.
What you’ll need
- Plug-in electricity usage monitorBudget price
Plugs in between the wall and a 120 V appliance and shows real watts and kWh over a day — the honest way to fill in a load list, especially for fridges that cycle on and off.
See options on Amazon (opens in a new tab)
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Frequently asked questions
How much does it cost to run a dehumidifier 24 hours a day?
About $3.20 a day, or $97.42 a month, at 785 W and 17¢ per kWh.
How much does a 400 W dehumidifier cost per month?
About $24.82 a month at 12 hours a day and 17¢ per kWh.
Other common sizes
- The cost to run a space heater — $0.26 an hour at 17¢/kWh (1,500 W)
- The cost to run a window AC unit — $0.17 an hour at 17¢/kWh (10,000 BTU)
- The cost to run a ceiling fan — $0.15 a day at 17¢/kWh (12 hours)
Sources
- Virginia Cooperative Extension, BSE-301: Estimating Appliance and Home Electronic Energy Use (2020) (opens in a new tab) — Wattage × hours ÷ 1,000 = kWh per day; watts = amps × volts when only amps are listed; a refrigerator runs at full wattage about a third of the time; typical nameplate wattages.
- Champion Power Equipment — Generator Wattage Chart (opens in a new tab) — Typical running and starting watts for household, RV and job-site appliances (a manufacturer’s planning chart — your nameplate wins).