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Cold Then Fold Featured on Aug 05, 2009

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Challenge Details

Rally Points

• Water heating is responsible for about 25% of a home’s annual energy expenses.
• Hot water typically accounts for about 90% of the energy used by a washing machine.
• A front-loading washing machine uses about 63% less water than a top-loading washer.

Yes, my washing machine is a lot more convenient than taking my clothes and sheets out to a river and beating them on a rock. But the wear-and-tear of repeated washing in hot water, with the fabric being pulled and twisted by the back-and-forth motion of the washer’s agitator, cannot be good for the long-term health of my Threadless tees. Luckily, I can save my clothes, save money, and save carbon by switching to colder washes. So can you.

This Featured Challenge is based on a number of great Challenge suggestions from our Challenge Workshop. We particularly want to give credit to violet, leader of the Green New York team. Violet’s suggestion has received 38 positive votes to date.

The Carbon Connection
You use hot water for showers and baths, to do dishes, and to do laundry. But that hot water doesn’t come pre-heated. It starts out as cold tap water. It takes energy for your water heater to make the cold water hot and to keep it hot and ready for you to use. And when you use some of that hot water, more energy is needed to heat the cold water that replenishes the tank. The energy used by the water heater likely comes from electricity or by burning natural gas. So chances are that your hot water is linked to the burning of fossil fuels and the emission of greenhouse gases such as carbon dioxide.

About 25% of the money you spend each year for your home’s energy is due to your need for hot water. According to the EPA, running a hot water faucet for just 5 minutes uses about the same amount of energy as burning a 60-watt bulb for 14 hours. So, limiting your demand for hot water can really reduce your energy use and CO2 emissions. And since laundry can be a big user of hot water, that’s a good place to start in cutting back.

Getting It Done
You already know how to choose different temperature settings on your washer. The only reason you don’t wash more of your clothes in cold water is that you were probably taught that “whites go in hot water, colors go in warm water, and anything special gets washed in cold.” But tell your mother that things have changed. Unless it’s very dirty or has some sort of grease stain, most of your laundry will get perfectly clean using cold water and today’s low-phosphate, biodegradable detergents.

Here are a few other things to think about when considering this Challenge:

• Try to do fewer loads of laundry. Run full loads, if you can. Remember, now that you are washing your clothes in cold water, you don’t have to separate your colors! And if you need to do a small load, be sure to use the water-level setting for a Small load.
• Remember that how you dry your laundry is the other energy-saving, carbon dioxide preventing part of this equation. If you haven’t already, consider taking our Sheets to the Wind Challenge and line dry some of your laundry this month.
• Consider replacing your old top-loading washer with a new, Energy Star-rated front-loading washer. These new washers use half the electricity and almost half the amount of water per load compared with the traditional top loader. The front loader doesn’t have an agitator, so it is gentler on your clothes. And it spins laundry faster, which removes more water and decreases the time it takes laundry to dry in a dryer or on the line.
• Some things belong in hot water. People with dust mite allergies may still need to wash their bed linens in hot water. Hot water is known to kill and remove dust mites, whereas cold and warm water do not.

Do you already wash your clothes in cold water? Do you use cold water for your sheets and towels as well? Have you found a laundry detergent that works particularly well in cold water? Please share your thoughts, stories, and suggestions on cold-water washing with fellow Rallyers in the forum section below.

Rules of the Challenge
This Challenge asks you to reduce your consumption of hot water by doing all of your laundry in cold water this month. If you do, you will be saving an estimated 30.4 lbs of CO2. This Challenge is repeatable and can be accepted once per month.

This Challenge is based on 10 loads of laundry per month. You may find that you and your roommate or family do more loads of laundry than that. If so, we suggest that you get your roomie or family members to join Carbonrally. Then they can take credit for the other loads of laundry that go cold turkey this month.

Learn More

The Daily Green: 10 Tips To Make Your Clothes Last Longer
Charity Guide: Wash Clothes in Cold Water (more tips on washing in cold water)
California Consumer Energy Center: Clothes Washers (a guide to choosing a new washing machine)
Energy Star: Clothes Washer Tips (other energy-saving tips on washing and drying laundry)

See the Math
Let’s start with the known or estimated numbers:

• Since top-loading washers are still found in most homes, we will say that you have a top-loading washer that uses 40 gallons of water per load. Assume that the wash and rinse cycles each use half (20 gallons) of that 40 gallon per load total.  source
• The typical setting choices for washing machines is Hot/Warm (a hot-water wash cycle, followed by a warm-water rinse cycle), Warm/Cold, and Cold/Cold. Let’s say that a hot wash cycle uses 20 gallons of hot water. And a warm wash cycle uses a 50/50 mix of hot and cold water, which means it uses 10 gallons of hot water. Cold wash and rinse cycles use no hot water.
• Based on the above, each hot-water load (Hot/Warm) requires 30 gallons of hot water (20 gallons for the hot wash cycle, plus an additional 10 gallons for the warm rinse cycle). Each warm-water load (Warm/Cold) requires 10 gallons of hot water. No hot water is required for the cold-water (Cold/Cold) load.
• According to the EPA, the average household does 392 loads of laundry each year. That comes out to about 7.5 loads of laundry each week or 32.6 loads per month.  source
• Of course, not all of you are in the average American household. For the purposes of this Challenge, let’s say you only do 10 loads of laundry per month. Furthermore, let’s say that, of those 10 loads of laundry, 4 of them are hot-water loads (Hot/Warm), 4 are warm-water loads (Warm/Cold), and 2 are cold-water loads (Cold/Cold).
• Your 4 hot-water loads use 120 gallons of hot water per month (30 gallons per load times 4 loads per month). Your 4 warm-water loads use 40 gallons of hot water per month (10 gallons per load times 4 loads per month). The 2 cold-water loads require no hot water. Your total is 160 gallons of hot water needed for laundry per month.
• This Challenge asks you to use only cold water to wash your laundry for the next month. By washing in cold water, you will not need the 160 gallons of hot water you might normally use.
• On average, heating 1 gallon of water requires an amount of energy (either electricity or natural gas) that contributes about 0.19 pounds of CO2 to the atmosphere. Reducing your use of hot water by 160 gallons per month saves 30.4 pounds of CO2 (0.19 pounds of CO2 per gallon of hot water times 160 gallons of hot water).  source
• Based on current energy costs, you save 2 cents for every gallon of water you don’t heat. By taking this Challenge, you will save a little over $3 on your utility bill in just one month!  source

Remember that the more loads of laundry you normally do, the more savings you can realize by making the switch to cooler water for your washing needs. According to the EPA, a family of four averages two to three times the number of loads of laundry used in this Challenge. That can easily mean energy savings of $100 or more a year by simply using colder water in the wash. Dial it down, Rallyers!

Discussion 57 comments so far

Eltra over 3 years ago

Cold water is the way to go! Try taking a cooler shower. You may even find it wakes you up in the morning!