And tougher environmental regulations are forcing manufacturers to build greener dehumidifiers.
Consumer Reports, Dan Diclerico said, "Most manufacturers are using a new refrigerant, which is less damaging to the ozone layer. And we found that these new, ozone-friendly dehumidifiers are just as good, if not better, at removing humidity than older models."
Consumer Reports tested 17 dehumidifiers, using a special environmental chamber to measure capacity - that's how much water they can remove per day.
"We generally recommend large-capacity dehumidifiers, which our tests show work more efficiently and therefore cost less to operate. But it's not about the physical size of the dehumidifier. Now these two models here are the same size, but this one has a claimed capacity of 65 pints per day, while this one has a claimed capacity of 32 pints per day."
And you can't count on the energy star to find an energy-efficient dehumidifier. These small units from Frigidaire and Haier carry the energy star - but they cost twice as much to operate as some larger units.
More efficient is this Danby Premiere, which is a Consumer Reports best buy at $200. It can remove 60 pints of water per day and received the top score for efficiency.
Consumer Reports says you should set your dehumidifier for under 50 percent humidity. That stops mold and dust mites from thriving. And if a space has a chronic musty smell or standing water, it's important to address the source of moisture.
That might involve patching your foundation, installing a sump pump, or adding bathroom exhaust fans.