A 35-pint portable dehumidifier draws about 342 W and costs $45.36 a month if the compressor runs 24 hours a day, at the U.S. average of 18.19¢/kWh — $11.34–$34.02 with a humidistat cycling it.
At 18.19¢/kWh — U.S. average, Jan–Aug 2026 (EIA).
| Period | kWh | Cost |
|---|---|---|
| Per hour plugged in | 0.342 | $0.06 |
| Per day | 8.2 | $1.49 |
| Per month | 249.4 | $45.36 |
| Per 12-month year | 2,993 | $544 |
| Capacity | Watts | Per month |
|---|---|---|
| 20 pints | 205 | $27.27 |
| 30 pints | 308 | $40.91 |
| 35 pints | 342 | $45.36 |
| 50 pints | 488 | $64.80 |
| Compressor on | kWh a day | Per day | Per month | Per year |
|---|---|---|---|---|
| 100% | 8.2 | $1.49 | $45.36 | $544 |
| 75% | 6.1 | $1.12 | $34.02 | $408 |
| 50% | 4.1 | $0.75 | $22.68 | $272 |
| 25% | 2 | $0.37 | $11.34 | $136 |
IEF (Integrated Energy Factor) is liters of water removed per kWh on the DOE test, so watts at rated capacity = liters per day ÷ IEF ÷ 24. With a humidistat the compressor stops once the air is dry enough, so real use depends on how damp the space is.
Prices: EIA U.S. average for Jan–Aug 2026. Efficiency: ENERGY STAR certified averages and 10 CFR 430.32 minimums.
The full method, material data and tips are on the main dehumidifier cost calculator page.