Dehumidifier Running Costs: How Much Electricity Does One Use?

A dehumidifier's electric cost is simple arithmetic: watts divided by 1,000 gives kilowatts, times hours run gives kWh, times your rate gives dollars. The examples on this page use $0.182 per kWh, our working figure for the average U.S. residential rate based on EIA's outlook. Your bill shows your actual rate, and the calculator below lets you use it.

The hard part is hours. A dehumidifier with a humidistat cycles: it runs until the room reaches the setpoint, then stops. In a damp basement in August it may run most of the day; in a dry month it may barely run. That is why ENERGY STAR's yearly estimate is a useful middle figure.

Dehumidifier energy use by size

ENERGY STAR publishes an integrated energy factor (IEF, liters of water per kWh) and an estimated yearly energy use for every certified model. Larger certified units are more efficient per liter, but use more energy in total because they remove more water:

Source: ENERGY STAR certified product records. Cost uses $0.182/kWh. Monthly figure is the yearly cost divided by 12; real use is higher in humid months and lower in dry ones.

Average monthly cost of running a dehumidifier

The table below shows cost per hour, per day and per month for common power ratings. A 200 watt dehumidifier is typical of a small compressor unit; 500 W is in the range of a 50 pint unit (Midea lists 480 W for its Cube 50); 700 W is a large basement or whole-home unit.

So the average monthly cost of running a dehumidifier in a damp basement, for a 50 pint unit running about half the day, is roughly $31 at our rate. A dehumidifier 200 watts running all day every day costs about $26 a month.

Real models: cost per hour and per day

Running 24 hours is the worst case. Most units on Auto spend part of the day idle with only the fan or nothing running.

Compressor vs desiccant power draw

In a warm basement, a compressor unit removes much more water for each kWh. A desiccant only wins on cost in cold spaces where the compressor would spend its time defrosting.

How to calculate your own cost

1. Find the watts on the unit's label or in the manual (some list amps instead; watts are roughly volts times amps, so about 115 times the amps for a U.S. unit, as an upper estimate).
2. Estimate hours per day. A plug-in energy meter gives you the real number after a week.
3. Find your rate on your electric bill, including delivery charges.
4. Multiply: watts / 1,000 x hours x rate = cost per day. Use the calculator at the top of this page.

Ways to cut running costs

• Set 45 to 50%, not lower. Each extra point of dryness costs run time.
• Use Auto, not Continuous. Continuous ignores the humidistat.
• Buy ENERGY STAR. Compare IEF on the ENERGY STAR record.
• Clean the filter monthly in the season.
• Close windows and doors to the space you are drying.
• Fix the water source: gutters, grading, leaks and dryer vents.
• Size correctly. An undersized unit runs nonstop and still fails to reach the setpoint.

Dehumidifier vs heating cost

Is it cheaper to run a dehumidifier or heating? They do different jobs. Heat lowers relative humidity because warm air holds more moisture, but the water is still in the air. A dehumidifier removes the water and adds a little heat too, because all the electricity it uses ends up as heat in the room. In a damp, unheated basement, a dehumidifier is usually far cheaper than heating the space enough to lower humidity the same amount. In a heated living space in winter, you often need neither.