Dehumidifiers are effective and generally energy-efficient tools to regulate indoor humidity. They use a lot less power compared to air conditioning. However, the electric costs of using one may raise some concerns. You want to minimize your electricity usage in order to reduce your carbon footprint while also saving money on utility bills.
Thankfully, running a dehumidifier doesn’t have to be too expensive. The amount of electricity it consumes mainly depends on its size, energy rating, and how often you use it. As long as you use the right size dehumidifier and maintain it well, you can optimize your usage.
It is a common misconception that dehumidifiers use a lot of electricity to run. Whether you need an energy-efficient dehumidifier for your household or a business, it helps to know the power usage and how much it will cost to run a dehumidifier. I’ll cover the basics of this below.
How Does A Dehumidifier Work?
Before we jump to the operating costs, it’s important that you understand how a dehumidifier works. I’ll cover the short version here but follow this link for more detail. There are two main types of dehumidifiers based on the methods they use to remove moisture: refrigerant and desiccant.
Similar to an air conditioner, a refrigerant dehumidifier uses condensation to collect moisture. It works by drawing in humid air and passing it over cold metal coils. As the air cools, the moisture condenses and drips into a tank or flows through a hose. The dryer air is then reheated and exhausted into the room. This type performs efficiently in warm climates.
A desiccant dehumidifier uses a desiccant chemical which absorbs moisture from the air. The humid air runs through the process zone of the desiccant rotor and the moisture clings to the surface of the desiccant. The heated air passes through the remaining part of the rotor, thus removing the moisture from the desiccant. The desiccant is now renewed so that it can adsorb more moisture. This dehumidifier is efficient in a wider range of temperatures.
Another method that is commonly used in mini dehumidifiers is the thermoelectric cooling or Peltier effect. Humid air enters through the cold side heat sink. The moisture condenses and the warmer, dryer air exits through the hot side. The process is similar to that of a refrigerant unit, but instead of using a compressor, a Peltier dehumidifier converts electricity into a temperature difference between the two sides of the Peltier module. As is the case with compressor models, the efficiency decreases in cool temperatures.
Power Usage and Energy Efficiency of a Dehumidifier
To find how much it costs to run your dehumidifier, you need to know the amount of power it draws, measured in Watts (W) or kilowatts (kW). This information is usually provided in the manual or on the unit itself. Mini dehumidifiers have an average wattage of 25 Watts; a 35-pint model draws around 300-500 Watts; while a standard 50-pint draws 500-700 Watts.
It’s also important to check the energy efficiency of your dehumidifier. This is called the energy factor, which is expressed in liters per kilowatt-hour (L/kWh). It tells you the volume of moisture the unit extracts using one kilowatt-hour of energy. A higher energy factor means a more energy efficient dehumidifier. You can find the energy factor of your device and compare it with others on the Energy Star website.
If you want to check the wattage on some specific models, check our guide for the best energy-efficient dehumidifiers here.
How to Calculate the Energy Cost of Your Dehumidifier
You can calculate the cost of running your dehumidifier given the following:
- Amount of power your dehumidifier draws. This is the power consumption we discussed in the previous section, measured in Watts or kilowatts. If the manufacturer indicates Volts and Amps instead, just multiply the two to get the wattage.
- Rate of electricity in your area. The cost of electricity varies per state and utility company. The average rate of electricity in the US is around $0.13/kWh at the time of writing. You may be able to find the exact amount on your electric bills.
Once you have these two figures, you can get an estimate of the hourly cost of running your dehumidifier using this formula:
Cost ($/hour) = Power Consumption (kW) x Electricity Rate ($/kWh)
Multiply the dehumidifier power consumption in kW with the rate of electricity in cents per kWh. Remember that one kilowatt is equivalent to 1000 Watts, so you need to divide the value by 1000 if the power consumption is expressed in Watts.
Average Operating Cost of a Dehumidifier
Using the above formula, let’s look at some common models of dehumidifiers and find their average operating costs per hour, per day, and per month. Assume that the rate of electricity is $0.13/kWh and you’re using the dehumidifier for eight hours everyday.
The Pro Breeze Mini Dehumidifier draws 23 Watts of power to extract up to 9 oz of moisture per day. The estimated hourly, daily, and monthly costs, respectively, are as follows:
0.023 kW x $0.13/kWh = $0.003 per hour
$0.003 per hour x 8 hours = $0.024 per day
$0.024 per day x 30 days = $0.72 per month
Now, let’s consider a full-size model. The Frigidaire 50-pint draws 545 Watts of power. The estimated hourly, daily, and monthly costs, respectively, are as follows:
0.545 kW x $0.13/kWh = $0.071 per hour
$0.071 per hour x 8 hours = $0.57 per day
$0.57 per day x 30 days = $17 per month
The Ivation 13-pint Desiccant Dehumidifier draws 470 Watts on high setting. The estimated hourly, daily, and monthly costs, respectively, are as follows:
0.47 kW x $0.13/kWh = $0.06 per hour
$0.06 per hour x 8 hours = $0.48 per day
$0.48 per day x 30 days = $14.4 per month
These are mere estimates given our assumptions. Your actual electricity cost can vary. Note that the dehumidifier will draw higher amounts of power in higher humidity environments.
Tips for Reducing Electricity Cost of a Dehumidifier
1. Use the right size dehumidifier.
The size of a dehumidifier refers to its capacity to remove moisture. Using the right size dehumidifier maximizes its effectiveness and efficiency. You may think that a smaller unit will save you more, but this isn’t true. If you use a dehumidifier with a smaller capacity than you need, it has to work harder for a longer period, yet it still won’t be able to drain out all the moisture.
To find the right size, measure the area of the space you need to dehumidify. If you want to use the unit in multiple rooms, get the area of the largest room. If you notice visible signs of moisture like condensation, mold growth, or rust on metal, go with a higher capacity unit. It’s better to get the next bigger size than you actually need so that the unit can accomplish the task quickly without working at the highest settings.
2. Choose an energy efficient model.
To further reduce your electricity costs, look for a dehumidifier with an Energy Star rating. Energy Star rated dehumidifiers are more energy efficient by up to 20% than a non-rated dehumidifier of the same size. Larger dehumidifiers are generally more energy efficient, but you should only get the right size for your space.
Concerns about the energy efficiency of dehumidifiers are still quite new. Because of this, modern dehumidifiers tend to use less energy than older models. Look for the Energy Star label to make sure you’re getting a dehumidifier with high energy efficiency. This label is only given to products that meet the EPA’s energy efficiency requirements for each type of appliance.
3. Limit your usage.
One obvious way to reduce your duhumidifer’s operating cost is by limiting your usage. You can do this by removing moisture through other methods.
Run your fans to increase the airflow in the area. Fans help circulate the air and they consume a lot less energy than the standard dehumidifier.
Improve your ventilation so that the moisture can get out instead of hovering in the air indoors. Open your doors, windows, or vents to exchange the humid air with some fresh air.
For small rooms, you can also use natural moisture absorbers like calcium chloride, sodium bicarbonate (baking soda), rock salt, or charcoal to lessen the load on your dehumidifier.
4. Remove humidity sources.
Check your plumbing. If there’s a leak somewhere in your house, you’ll notice damp spots on your walls or floor along with high indoor humidity. Repair the leak before running your dehumidifier. Clogged gutters can also raise humidity levels so make sure to keep them clean and clear.
Some common household activities can cause humidity as well. When you take a shower or cook, make sure to open a vent or run an exhaust fan to keep the moisture out. Also avoid hanging wet laundry indoors. Use a dryer or fan, or dry them outside if possible.
5. Use your dehumidifier properly.
Dehumidifiers generally perform well in warm temperatures and start to experience problems when operated at 65F or lower. If the air gets too cold, the condensate may freeze on the coils. The unit will have to stop dehumidifying to melt the ice, thus reducing its efficiency. If you get really cold winters in your area, a desiccant dehumidifier may be best. Full-size models can work efficiently down to 33F.
Frequent cleaning of your dehumidifier also helps maintain its effectiveness and efficiency. Unplug it and wipe off any grime on the exterior. If your dehumidifier uses a tank, empty it and clean thoroughly. Take out the air filter and wash it or replace it as needed. Vacuum the interior to remove any remaining dirt or debris. Let everything dry before reinstalling.
In conclusion, there is no fixed amount for the power usage and electricity cost of a dehumidifier. It can vary depending on its capacity and the indoor environmental condition. You can estimate the cost of running a dehumidifier before you purchase one by getting the power consumption of the unit and the rate you pay for electricity. Consider the size and energy efficiency to get the most out of your investment. If you already own a dehumidifier, you can reduce costs with proper usage and maintenance.