How Much Electricity Does a Dehumidifier Use?
A standard dehumidifier uses 300-700 watts, costing $15-40 per month running 12-24 hours daily. Energy Star models use 15-20% less. Use the Power Cost Calculator to calculate your exact costs.
Key Takeaways
- Dehumidifier wattage depends on capacity (measured in pints per day).
- Whole-house dehumidifiers use more power but often run less than portable units.
- Energy Star dehumidifiers save $20-40 per year compared to non-certified models.
Explanation
Dehumidifier wattage depends on capacity (measured in pints per day). Small units (20-30 pints) use 300-400 watts, medium units (50-60 pints) use 500-600 watts, and large units (70+ pints) use 600-800 watts.
A 500W dehumidifier running 12 hours daily uses 180 kWh monthly, costing about $29 at $0.16/kWh. In very humid conditions requiring 24/7 operation, costs can exceed $50/month.
Built-in humidistats allow units to cycle on and off, reducing runtime. Setting humidity to 50% instead of 40% can significantly reduce operating time and costs.
Compressor-based dehumidifiers work best when room temperature is above 65°F. Below that temperature, frost forms on the coils and the unit cycles into defrost mode, dramatically reducing moisture removal and wasting energy. For basements or garages that stay below 60°F, desiccant dehumidifiers perform better and maintain consistent efficiency in cold conditions.
The energy factor (EF) rating measures how many liters of water a dehumidifier removes per kWh of electricity. Energy Star models require an EF of at least 1.57 L/kWh for units rated up to 35 pints per day and 2.8 L/kWh for larger units. Choosing a model with a higher EF directly translates to lower operating costs per pint of moisture removed.
Placement affects both performance and energy use. A dehumidifier placed near the center of a room with doors and windows closed removes moisture faster and runs fewer hours than one tucked in a corner. Keeping the air filter clean is equally important—a clogged filter restricts airflow and forces the compressor to run up to 20% longer to reach the target humidity.
Running a dehumidifier year-round is rarely necessary and wastes significant electricity. In most U.S. climates, indoor humidity only requires active dehumidification from May through September. Using a hygrometer to monitor humidity and only running the unit when levels exceed 55% can cut annual dehumidifier electricity costs by 40-50% compared to continuous operation.
Things to Know
- Whole-house dehumidifiers use more power but often run less than portable units.
- Energy Star dehumidifiers save $20-40 per year compared to non-certified models.
- Proper home ventilation can reduce the need for dehumidification.