How much does a dehumidifier cost to run?

It depends on its power rating (often 200 to 700 watts), how long it runs, and your power price. Run for a few hours a day over winter, a typical dehumidifier might cost a few dollars a week, which adds up across the colder months.

Is a dehumidifier cheaper than heating?

A dehumidifier uses far less power than most heaters, and a drier home is easier and cheaper to heat. Running one to control damp can reduce both heating costs and the health problems that come with a damp home.

How can I reduce the cost?

Use the humidistat so it only runs when needed, run it in a closed room, and fix the sources of moisture (ventilation, drying washing outside). A more efficient model also uses less power for the same result.

Dehumidifier Running Cost Calculator

This calculator works out what it actually costs to run a dehumidifier in your New Zealand home, so you can budget for keeping damp under control over the colder months without guessing at the power bill. You enter the appliance's power rating in watts, how many hours a day you run it, your electricity price per kWh, and how many months of the year you use it, covering a typical damp season through winter. From these figures the tool returns the cost per day, the cost per week, and the total cost over the season you run it, converting the wattage to kilowatts and multiplying through your usage and power price. Use it to compare running costs between different dehumidifier models before you buy, or to see how much a few extra hours a day on the humidistat setting adds up to across a season. The figures assume the unit runs at full power for every hour entered, so if yours cycles on and off via a humidistat once the room reaches the target humidity, your real bill will usually come in lower than the estimate shown. Keeping a home dry also makes it cheaper and easier to heat, and reduces the health problems that come with damp and mould, so weigh the running cost against those savings. This is an indicative estimate only, based on the figures you enter.

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Power rating (watts)

Hours per day

Power price (per kWh)

Months used per year

cost over the season you run it

Per day$0

Per week$0

Assumes it runs at full power for the hours entered; using the humidistat means it cycles off and costs less. A drier home is cheaper to heat and healthier. Estimate only.

How it works

The calculator converts the power rating to kilowatts, multiplies by the hours run per day and your power price for the daily cost, then scales it to a week and across the months you use it. Most dehumidifiers cycle on and off via a humidistat, so real cost is usually a bit lower than the full-power figure, but this gives a solid upper estimate for budgeting.

Worked example

A 350 watt dehumidifier run 6 hours a day at 28 cents uses about 2.1 kWh, around $0.59 a day or $4.12 a week. Over a 5-month damp season that is roughly $88, less if the humidistat cycles it off.

Related calculators

Appliance Running Cost Calculator: any appliance.
Clothes Dryer Cost Calculator: dryer cost.
Heat Pump Savings Calculator: heating savings.
Electricity Cost Calculator: power costs.

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