More than 60% of Americans still wash their laundry in warm water. It’s a practice that’s as costly as it is environmentally unfriendly. What’s more, it doesn’t make our clothes appreciably cleaner. Here’s why you should make the switch to cold water.
Given that we all have to do it, it should come as little surprise to learn that laundry exerts a significant global footprint. Of the total energy use and greenhouse-gas emissions produced by a single load of laundry,approximately 75% of it comes from warming the water itself.
There’s also the cost to consider. According to Consumer Reports, doing laundry in cold water will save you upwards of $60 per year (or more if you live in an area with higher-than-average electricity rates), assuming an average of 300 loads per year. That may not sound like much, but it’s significant when considering the pressure placed across the entire electrical grid.
Think of it this way: If every Las Vegas household switched to cold washing for an entire year, the amount of energy saved could power its famous Strip for nearly a week. If every household across the U.S. switched to cold water for an entire year, that would save the same amount of energy produced by the Hoover Dam in 20 months.
As noted by Leigh Krietsch Boerner at The Sweet Home, “[U]nless you have a really good reason for washing in warm or hot, such as really stinky clothes or cloth diapers, go for cold. It saves energy, and your clothes will last longer.”
Indeed, cold water is actually good for certain clothes. Lower temperatures protect the dyes, and therefore the color of clothes, while also helping to preserve the fit of the clothes by preventing shrinkage, particularly along the seams. What’s more, some stains, like blood, should only be washed in cold water. Warm water just makes blood stains set in.
So aside from some rare instances, there’s really no reason for you to keep washing your clothes in warm water. The Laundry Goddess offers some practical tips:
Personally, I have found that you can wash everything in cold water successfully, as long as you follow a few basic rules: Only use liquid detergent, as most powders need warm water to completely dissolve and clean successfully. Use the proper amount of detergent – too little and your wash load will not come clean, and too much will leave a soapy residue behind on your wash.
Also, do not overload the washer; be sure to leave room for items to move around in the water.
Now all this said, warm water does play an important role in helping to make your clothes clean. Well, provided you use high performance detergents and washing machines — and provided you follow the manufacturer’s instructions. Using too much or too little detergent can result in sub-optimal performance, as can using the detergent at the wrong temperature. Using a standard warm-water detergent in cold water, for example, may not get you the results you want. So, unless you opt for a specifically cold water detergent, you may not notice that the warm water is cleaning better. But the fact of the matter is that you can get just as clean with cold.
Laundry involves a number of chemical reactions — reactions that go faster at higher temperatures. So, along with chemicals and mechanical energy, the thermal energy produced by warm water helps to get rid of stains, dirt, and residue on our clothing. Until very recently, most detergents were designed with this in mind. Owing to a demand for more environmentally friendly solutions, detergent manufacturers have now found ways to create detergents that work remarkably well in cold water. But to do so, they had to get around some very tricky chemical constraints.
One of the biggest challenges to developing detergents that work in cold water, or regular “tap water,” is that tap water temperatures are inconsistent across geographical locations and seasons. For example, “cold” water in Florida during the summer months is ~80 degrees F, while “cold” water in Minnesota during the winter months can dip as low as ~40 degrees F. Consequently, cold water detergents need to work effectively across a surprisingly large spectrum of temperatures.
To complicate things even further, surfactants — the so-called “work-horse” of detergents — don’t perform as well in cold water. These chemicals, which comprise upwards of 30 to 40% of the weight of detergents, lift and removes stains. They involve a class of chemicals known as linear alkyl benzene sulfates — long chains of a chemical called a dodecane.
Writing in C|Net, Richard Baguley and Colin McDonald explain how surfactants work: