Appliance Cost Lab

Dehumidifier guide

How much electricity does a dehumidifier use?

A schedule estimate multiplies compressor-on watts by scheduled hours and duty cycle, but representative multi-hour or full-day measured kWh better captures real cycling.

Do not treat elapsed time as compressor-on time. Humidity, temperature, set point, fan mode, frost control and drainage affect cycling.

Three reproducible schedule scenarios

Three published dehumidifier electricity-cost scenarios
Scenario Inputs Active cost per scheduled day Annual energy Annual cost
300 W for six scheduled daily hours at 50% duty 300 W; 6 h/day; 7 days/week; 50% duty; 1 W standby for 18 h/day; $0.18/kWh $0.16 active/day 335.070 kWh $60.31
400 W for eight scheduled daily hours at 60% duty 400 W; 8 h/day; 7 days/week; 60% duty; 1 W standby for 16 h/day; $0.18/kWh $0.35 active/day 706.640 kWh $127.20
500 W for twelve scheduled daily hours at 70% duty 500 W; 12 h/day; 7 days/week; 70% duty; 1 W standby for 12 h/day; $0.18/kWh $0.76 active/day 1,537.380 kWh $276.73

$0.18/kWh is an illustrative comparison rate, not a national or current market price. These duty cycles are arithmetic inputs, not performance claims.

Measure the operating conditions you actually have

Rated watts multiplied by elapsed time can overstate energy whenever the compressor cycles. A representative multi-hour or full-day kWh measurement captures compressor, fan, frost-control and bucket/pump behavior under the observed humidity and temperature.

ENERGY STAR rates efficiency using liters removed per kWh under defined test conditions. That metric and the product’s capacity are useful for comparison, but they do not predict a room’s schedule without its conditions.

Safety and control functions

Smart-plug evaluation requires explicit Yes and visible confirmation. Check instructions, ratings, automatic restart, continuous drainage or pumps, freeze protection and any required humidity-control function. The site makes no health, mold-prevention or indoor-air-quality guarantee.
Sources: ENERGY STAR Dehumidifiers and Dehumidifier Testing and Capacity support the cycling, capacity and measured-efficiency distinctions; they do not validate these scenarios.

Open the dehumidifier schedule calculator

Related: space-heater guide · portable-AC guide · window-AC guide · refrigerator guide · methodology · accuracy · sources · standby power

Last reviewed: August 14, 2026