Last week, we took a look at how to save energy and water with clothes washing. This week we’ll turn our attention to drying, which accounts for approximately 6% of all household electricity consumption in the U.S.
The two are closely related. The more effectively we extract water from clothes during the spin cycle of washing, the less energy it takes to dry them. That’s another reason the new horizontal-axis (H-axis or front-loading) clothes washers are so good. The extremely fast spin speeds remove far more moisture than vertical-axis top-loaders—and more than some H-axis machines.
When we traded in our older, entry-level Frigidaire H-axis on a new Whirlpool Duet mode, the difference in water removal was dramatic. It seemed that the clothes came out of the washer only damp, cutting the drying time nearly in half. Moisture is removed so effectively because our new washer has a maximum spin speed of 1,100 revolutions per minute (rpm) vs.–I think–700 rpm for our old Frigidaire. (Newer and higher-end Frigidaire washers have significantly faster spin speeds.)
The German company Miele sells washers in the U.S. with spin speeds up to 1,600 rpm, and I’ve read online testimonials claiming drying times of 15-20 minutes when using these models. And I just learned that the Slovenian company Gorenje makes clothes washers with spin speeds up to 2,000 rpm, though these products are not sold in the U.S. (yet).
If you’re in the market for a new dryer, look for a model that senses remaining moisture so that the dryer doesn’t keep operating once clothes are dry. Also, a dryer with a “cool-down” cycle will shut off the heating element when the clothes are nearly dry, allowing the residual heat to complete the job.
Then install, operate, and maintain the dryer properly. Make sure that the venting line is as short and straight as possible to avoid restricting airflow. To save energy during operation, keep the lint filter clean, avoid overloading, and wash similar clothes together (because some fabrics dry more quickly than others). If you take out clothes before they are 100% dry and hang them up, you’ll save a bit on drying and reduce the need for ironing—another energy use associated with laundry.
For the most energy-efficient clothes drying, the solution is to use a clothesline instead of a dryer. There are a number of reasons people don’t hang laundry outdoors: too little time, inclement weather, preference for softer clothes that have been tumble-dried, soiling from pollution (including outdoor wood boilers) or sap dripping from trees, prohibitions against hanging laundry outdoors in some places, and simple laziness. Some of these certainly apply to me—mostly in the inclement weather and laziness areas!
Years ago I gained a lot of experience with clothesline drying. It surprises many people to learn that clothes will dry outdoors even in very cold weather. The clothes freeze, but then the frozen water evaporates through the process of “sublimation” (direct conversion of solid to gas, without first going through a liquid phase).
Hanging laundry on a clothesline increases the life of your clothes. Every time you empty the lint filter in a dryer, that lint you’re taking out represents a shortened life of the clothes that were just dried.
Hanging laundry indoors can help humidify the indoor air. Leaky houses in cold climates get very dry in the winter because the outdoor air leaking in hold very little moisture. Evaporating moisture from clothes introduces humidity without also putting fine mineral particles into the air (as happens with low-cost humidifiers). Note that I do not recommend venting an automatic dryer into a home.
Don’t even think about venting a gas dryer indoors, because doing so would introduce combustion gases. But even an electric dryer should not be vented indoors, because the airborne fibers from the clothes can cause respiratory irritation.
Unfortunately, drying clothes outdoors is illegal in many places. According to an article last month in the New York Times, about 60 million people in the U.S. live in private communities, and a majority of these prohibit outdoor clothes drying. At least four states (Vermont, Maine, Colorado, and Hawaii) have overridden those prohibitions in the past year with laws that protect residents’ rights to hang clothes outdoors. Florida and Utah already had such laws, and similar measures are being considered in Maryland, Virginia, North Carolina, and Oregon. The “right to dry” movement is clearly growing nationally.
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