A dehumidifier collects water vapor from the air, decreasing the humidity of the surrounding area. Dehumidifiers include both portable and whole-home dehumidifiers. Portable dehumidifiers can be easily moved from one room to another, while whole-home dehumidifiers are often used in conjunction with a home’s HVAC system and are designed to be connected to ductwork. Dehumidifiers work by using a refrigeration system to cool air to the point where moisture in the air condenses.
Congress established initial national standards for dehumidifiers as part of the Energy Policy Act of 2005 (EPAct 2005) and updated those standards in the Energy Independence and Security Act (EISA) of 2007. In 2016, DOE finalized new standards for dehumidifiers, which took effect in 2019. Relative to the previous standards, the current standards represent energy savings of about 15-25%. The standards are based on a new metric, integrated energy factor (IEF), which incorporates energy consumed when the fan is running while the refrigeration system is off and standby power consumption, in addition to the energy consumed by the refrigeration system. IEF is expressed in terms of liters of water removed per kWh of electricity consumed. The new standards are also based on an improved test procedure that will better reflect the actual energy consumption of dehumidifiers used in homes. Previously, dehumidifiers were tested at an ambient temperature of 80 F. With the new test procedure, dehumidifiers are tested at 65 F, which better reflects typical basement temperatures.
About 14% of US homes use a dehumidifier. The efficiency of dehumidifiers can be improved through the use of more efficient compressors and larger heat exchangers.