May Energy Tips: Dehumidifiers
With spring comes rain and we have certainly not been lacking rainfall recently. As we turn off the heat in our homes, we may find excess moisture is an issue. Portable dehumidifiers are a great way to combat this problem, so this month's email will look at moisture and dehumidifiers.
You are welcome to contact me with questions or to make a topic suggestion. Please email me at lhensley@central.coop.
Do you have a humidity problem in your home?
There are a number of things to consider when your home is burdened with excess moisture. Understanding why the issue exists in your spaces will help you take control of the problem. If you have moisture issues in your home, here are several considerations:
- Check your attic for roof leaks and check your crawl space or basement for standing water or plumbing leaks.
- Make sure you are using exhaust fans when bathing and cooking, and letting them run for a few minutes after the water is off and the food is ready.
- Ensure your HVAC ductwork is properly sealed to avoid outside air getting in. Check for other places where moist outside-air could enter your home, such as holes and openings around doors and windows, in the ceiling around light fixtures, on the floor, and around attic hatches.
- Clean your gutters and downspouts. Make sure the ground slopes away from your home so water does not enter or build up around the foundation.
- Cover the ground of your crawl space with plastic sheeting. A 6-mil polyethylene cover overlapping the seams by 12 inches works well.
So how does all of this relate to your electric bill?
Many of our members combat the issue of excess moisture with a portable dehumidifier. The amount of electricity required to operate a portable dehumidifier varies and so will the time required for it to do the necessary job.
Here is an example:
One 50-gallon Energy Star rated dehumidifier requires 530 watts to operate. Let’s suppose in order to keep the space at a relative humidity of 40%, the appliance operates for 12 hours each day. (The residential rate per kWh for CEC is $0.108890.)
(530 watts/1000 watts) = 0.53kW x 12 hours = 6.89 kWh
6.89 kWh x $0.108890 = $0.75 per day
So it will cost $0.75 each day that the dehumidifier runs for 12 hours. The cost for a month of constant operation would be $22.50.
Dehumidifier Basics
Capacity: Refers to the number of pints that can be pulled from the air in a 24-hour period. The chart below, shared by energystar.gov, can help to size a dehumidifier for your needs.
Water Removal Options: Look for units with lights indicating the bucket is full and needs to be emptied. If using in a basement, look for units that can drain water directly into a floor drain if your home has one.
Placement: For best operation, make sure dehumidifiers are placed away from walls and furniture and sources of dust and dirt. Doors and windows should be closed in spaces where dehumidification is taking place.
Temperature: If the space you are using the dehumidifier has an air temperature less than 65 degrees, make sure the unit is rated for it.
Relative Humidity (RH): RH is the amount of water vapor actually present in the air compared to the greatest amount of water vapor the air can hold at that temperature. The optimum RH level for a building is generally between 30% and 50%. Anything above this range may promote bacteria growth. Many dehumidifiers include a built-in humidistat, which allows you to set the desired RH level you would like for the room. Once the room reaches the desired RH level, the dehumidifier will cycle on and off automatically to maintain the level.