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All About Washing Machines

The best clothes washers save water and energy compared to older models — but most of the energy used for laundry is gobbled up by your clothes dryer

Posted on Mar 7 2014 by Martin Holladay, GBA Advisor

About 82% of U.S. homes have a clothes washer. Each of these appliances is used, on average, to wash about 300 loads of laundry per year. On an annual basis, residential clothes washers use more energy than dishwashers but less than refrigerators.

In recent years, appliance manufacturers have developed washing machines that use less water than older models. The average full-sized front-loading Energy StarLabeling system sponsored by the Environmental Protection Agency and the US Department of Energy for labeling the most energy-efficient products on the market; applies to a wide range of products, from computers and office equipment to refrigerators and air conditioners. clothes washer uses about 15 gallons of water per load — and some models use less than 12 gallons — compared to about 23 gallons per load for a top-loading clothes washer without an Energy Star label.

Top-loader or front-loader?

Although there are a few exceptions, most clothes washers fall into one of two categories: they are either traditional top-loading (vertical-axis) models or newer, European style front-loading (horizontal-axis) models.

Front-loading machines cost more than top-loading machines, but (on average) they perform much better:

  • Because front-loading machines tumble the clothes through a shallow puddle of water rather than submerging the clothes in a huge tub, they use less water.
  • The spinning action of front-loading machines is gentler on clothes than the vigorous action of an agitator; this gentler approach probably makes clothes last longer.
  • Front-loading machines require less laundry detergent than top-leaders.
  • During the final spin cycle, front-loading machines spin faster than top-loaders, so they remove more water from the damp clothes.

[Credit for bar graph: ACEEE]

Because of these many advantages, front-loading washers have acquired a dramatically increased share of the market for residential clothes washers in recent years.

Do efficient washers get clothes as clean as inefficient washers?

In 2007, after testing new energy-efficient clothes washers, Consumer Reports magazine reported that some washing machines performed poorly — in other words, they didn’t get clothes very clean.

Fortunately, the magazine’s latest article on clothes washers (August 2012) reported good news: the performance problems with the first generation of energy saving washers have been solved. The authors noted that “good cleaning, high efficiency, and large capacities are common features of the newest washers.”

How important is it to wash in cold water?

If you have a clothes washer, you probably realize that doing a load of laundry involves the use of one, two, or three energy-using appliances:

  • A clothes washer;
  • Sometimes, but not always, a water heater;
  • Sometimes, but not always, a clothes dryer.

According to many writers, the most important step you can take to reduce the energy used to do a load of laundry is to switch from hot-water washing to cold-water washing. While following that advice will still save energy, the development of water-stingy clothes washers has made the advice obsolete.

These days, the best advice for those who want to reduce the amount of energy used for laundry is, “Use a clothesline.”

Researchers have measured energy use and water use

For up-to-date data on the amount of energy and water that Americans use for laundry, it’s worth reading a report written by two California researchers, David Korn and Lauren Mattison. The report, “Do Savings Come Out in the Wash?,” was published in the January/February 2012 issue of Home Energy magazine.

Korn and Mattison measured the amount of energy and water used for clothes washing and clothes drying in 115 California homes. “In all, we studied 24 non-Energy Star clothes washers and 91 Energy Star-qualified clothes washers,” the researchers reported. “The average electricity use of the 24 baseline machines — those that met the federal standard but were not Energy Star-qualified — was 0.21 kWh per cycle. The average electricity use of all 115 machines was 0.20 kWh per cycle. This small difference is not statistically significant.”

That’s right: Energy Star clothes washers use the same amount of electricity as clothes washers that don’t have an Energy Star label. “Unlike other energy-efficient appliances, efficient clothes washers use about the same amount of energy as standard models. They save energy by using less water to wash clothes, and by removing more water at the end of the wash cycle, thereby allowing for shorter dryer cycles.”

Energy Star washing machines may not save much electricity, but they do save water: “The average Energy Star machine used 55% less water than the average non-Energy Star machine.”

It’s no longer about hot water — now, it’s all about the drying

Korn and Mattison explain that homeowners who wash clothes with cold water instead of hot water aren’t saving as much energy as they used to. They wrote, “Efficient clothes washers use as little as 12 gallons of water per load. Hot water represents only a small part of this amount even for hot cycles.” (After all, even when you choose the “hot wash” cycle, most washing machines use cold or warm water for the rinse cycle.)

All of the homes where Korn and Mattison collected data had electric clothes dryers. The occupants of the homes were not given any instructions concerning whether to use hot water or cold water to wash their clothes; some chose hot, some chose warm, and some chose cold. The two researchers measured how much energy was used to operate the clothes washer, as well as how much energy was used to heat water for laundry and to dry the clothes. The largest energy use, by far, was for the clothes dryer.

For residential laundry, 81% of the energy used goes to operate the clothes dryer; 13% of the energy goes to heat water used for laundry, and only 6% of the energy goes to operating the clothes washer. (While the percentages will differ for homes with gas dryers, it's safe to say that clothes dryers use more energy than today's efficient washing machines.)

The bottom line: Use your clothesline! (For more information on clothes drying, see Alternatives to Clothes Dryers.)

Don’t forget to consider standby power

Unlike older washers, newer models of clothes washers unfortunately have a measurable “phantom load” — in other words, they use electricity constantly, even when they appear to be “off.” According to Korn and Mattison’s measurements, this standby load averages 0.34 kWh per week.

Since a washing machine requires only 0.21 kWh per load of laundry, homeowners who only wash one or two loads of laundry per week will find that a significant percentage of the electricity used by their washing machine (45% to 62% of the machine’s electricity use) is devoted to standby power. That’s a lot.

Shopping for a new clothes washer

If you are an energy-conscious homeowner who is shopping for a new washing machine, you’ll need to learn how machines are rated. The two most important metrics used by the federal government to rate washing machines are the modified energy factor and the water factor.

The modified energy factor (MEF) is calculated by dividing the clothes washer capacity (in cubic feet) by the power (in kWh) used for one load of laundry by the clothes washer and the clothes dryer; this calculation includes the energy required to heat water for one laundry load. Since the MEF calculation takes into account the energy needed to dry clothes, it rewards washers with a high-speed spin cycle. (High-speed spin cycles remove most of the water from damp clothes, reducing drying time.) The higher the MEF, the more efficient the washing machine. At this time, federal regulations require that residential clothes washers have a minimum MEF of 1.26. The minimum MEF for Energy Star clothes washers is 2.0.

The water factor (WF) is calculated by dividing the amount of water used for one load of laundry (in gallons) by the clothes washer capacity (in cubic feet). The lower the WF, the more efficient the washing machine. At this time, federal regulations require that residential clothes washers have a maximum WF of 9.5. The maximum WF for an Energy Star clothes washer is 6.0.

Efficient washers

If you are shopping for a clothes washer, you will probably be looking for a front-loader with an Energy Star label. Choosing a washer without an Energy Star label is false economy, since the upcharge for an Energy Star washer has a fast payback.

You want a model with a high MEF and a low WF.

If you follow this advice, you’ll end up with a machine that uses electricity and water frugally. However, these newer machines take longer to wash clothes than older models. (Back in 2005, the average old-fashioned top-loading machine required 50 minutes per load. In 2012, the newer front-loaders average 79 minutes per load.)

If you are comparing the energy consumption shown on the yellow EnergyGuide labels, note that the kWh shown on the yellow label includes washer energy and water-heater energy, but not the energy used by the clothes dryer. If you care about how effective a washer is at spinning moisture from clothing — and you should — it makes more sense to compare MEFs than to compare yellow EnergyGuide labels.

There are several online databases that you may want to consult before you buy a new clothes washer:

Encouraging trends

Over the last two or three decades, clothes washers have gotten more efficient; moreover, somewhat surprisingly, they have also gotten cheaper. According to a document published by the Appliance Standards Awareness Project, “Between 1987 and 2010, real prices decreased by about 45% while average energy use decreased by 75%.”

While recent improvements in appliance energy efficiency are commendable, history shows that most appliance manufacturers would never have improved the efficiency of their products unless the federal government had ratcheted up its mandatory appliance efficiency standards.

Finally, it’s worth noting that appliance manufacturers still aren’t very good at disclosing energy use or water use information. As writer and musician Michael Bluejay notes on his website, “Shame on washing machine manufacturers for not publishing specs. No U.S. washing machine manufacturer bothers to publish energy and water use per load specs in their user manuals or on their websites.”

• • • • • • • • • • • •

Author's postscript: An unrelated update on garage door openers

[Back in July 2013, I wrote an article on garage door openers and phantom loads. In that article, I announced my intention to measure the phantom loads and energy requirements for several brands of garage door openers. Unfortunately, life intervened, and I haven’t been able to measure many doors. However, I do have some limited data to report:]

The manufacturer of the LiftMaster 8550 garage door opener claims that its standby load is only 1 watt. However, according to my measurements, the actual standby power draw for this brand of garage door opener is 3 watts, putting the standby energy use of this device about in the middle of the range of openers tested by researchers from Lawrence Berkeley National Laboratory.

So the LiftMaster 8550 uses 72 watt-hours a day, or 26 kWh per year, to wait for a signal.

The door opener draws 118 watts when it is opening or closing the door; this operation takes between 12 and 15 seconds. If the door is operated 4 times a day, it uses only 2.0 watt-hours per day, or 0.72 kWh per year, to open and close the garage door. Under these circumstances, the garage door opener uses 36 times as much electricity to wait for a signal as it does to open and close the garage door.

The good news: even though most of the electricity used by the door opener is a "phantom load," the total annual electricity use isn't much. If used as described above, one garage door opener uses about $3.38 of electricity per year, while two openers use about $6.76.

Martin Holladay’s previous blog: “Exhaust-Only Ventilation Systems and Radon.”

Click here to follow Martin Holladay on Twitter.

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  1. Samsung
Fri, 03/07/2014 - 11:05

Edited Fri, 03/07/2014 - 11:05.

what about the well pump?
by David Fay

Helpful? 1

One thing everyone seems to overlook when looking at washing machines is the electricity needed to pump water from the well. At 40 gallons per cycle for older washing machines and 300 loads per year, that's 12,000 gallons of water that must be pumped in a year just to do the wash. Yes, it only applies to those of us that have wells, and yes, it's probably not a lot of electricity, but it would be nice to see some accounting for this in the analyses.

Fri, 03/07/2014 - 11:25

Edited Fri, 03/07/2014 - 11:26.

Response to David Fay
by Martin Holladay, GBA Advisor

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You're right, of course; rural homeowners often use electricity to bring water into their homes. The energy required for this purpose varies widely, from no energy at all if you have a gravity-fed spring, to significant amounts of energy if you have a very deep well (say, more than 600 feet deep).

Estimates of typical energy use for residential deep-well submersible pumps vary; according to one source, a typical range is 15 to 30 kWh/month; according to another source, 60 kWh/month is more typical. That gives us range of 180 kWh to 720 kWh per year, or about $25 to $100 per year.

Fri, 03/07/2014 - 14:00

"carbon footprint" of city water
by Matt Dirksen

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Hi Martin,

It's great to hear that washers (and heat pump driers) are getting more efficient, more reliable, and more accessible. But your article got me thinking. In the spirit of understanding "total energy use", I was wondering if you had any recent data on on the amount of energy used by public utilities to bring us fresh water (and to treat it through the sewage system?)

I kind of recall reading once that the carbon footprint of fresh tap water was rather high, and tends to be overlooked when thinking about total energy consumption.


Fri, 03/07/2014 - 14:22

Edited Fri, 03/07/2014 - 14:52.

Response to Matt Dirksen
by Martin Holladay, GBA Advisor

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The amount of energy required to deliver a gallon of municipal water is all over the map -- from very little in New York City (which has a water system that is pressurized by gravity) to very significant in California.

There are lots of documents discussing the issue -- especially for California, which may be the worst-case scenario. Here are some links:

ENERGY DOWN THE DRAIN: The Hidden Costs of California’s Water Supply: "The amount of energy used to deliver that water to residential customers in Southern California is equivalent to approximately one-third of the total average household electric use in the region."

California's Water-Energy Relationship

Water-Energy Connection

Fri, 03/07/2014 - 15:36

The things that make me go ummmhhh!...
by Armando Cobo

Helpful? 0

So, for those folks that dry their clothes outside, has anyone calculated the energy used in ironing clothing and linen? How about lost revenue to a client that thought your shirt looked like was cleaned in the back of your pickup truck? How about lost quality time with your children because you have to spend hours and hours ironing? Also, that time can be used to help your kids with their homework; or maybe those folks abuse their kids making them do the ironing, eh?... I guess I better stop ummmhhing!

Fri, 03/07/2014 - 21:03

by aj builder, Upstate NY Zone 6a

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Front loaders.... mold issues The good, bad and ugly, of progress.

Fri, 03/07/2014 - 21:22

We must have used more energy for clothes in the 50s
by Robert Connor

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That was back when everybody dressed sharp. You really don't need to worry that much about energy for ironing now because most clothes have some polyester that helps resist wrinkles and people dress more casually. Back in the 50s it was all cotton and everyone, at least in the movies, was a sharp dresser.

Armando, if you really are concerned about energy, then why have kids? The most energy hungry activity any human can do is create children. Having 1 child will increase your carbon score by a factor of 6!

Oh, and I find that hot water is necessary for most clothes but by the time it gets into a front loader it is barely warm. Some FL have heaters but they take a long time. Cold water does not remove odors.

Sat, 03/08/2014 - 05:30

Response to A.J. Builder
by Martin Holladay, GBA Advisor

Helpful? 0

Your reference to "mold issues" confuses me. What problems have you experienced?

Are your clothes moldy? Is your laundry room moldy?

Why do you think that your washing machine is to blame for your mold problems?

Sat, 03/08/2014 - 05:35

Response to Armando Cobo
by Martin Holladay, GBA Advisor

Helpful? 0

Like Robert, I think that your worry about ironing is a red herring. People who want the crisp, ironed look for their clothes are probably going to continue to iron their clothes, whether they use a clothes dryer or a clothesline.

And people who don't need a very crisp, ironed look -- or who buy clothes that don't require ironing -- aren't likely to pull out an iron just because they use a clothesline instead of a dryer.

Sat, 03/08/2014 - 09:05

Edited Sat, 03/08/2014 - 09:08.

Reliability vs. cost
by bob holodinsky

Helpful? 0

I have been in the appliance industry for over 3 decades and my unofficial observation is the hefty price of the front load washing machines wipes out any savings on water advantage .It was not uncommon for a conventional washer to last 15 to 20 years with very little service. That does not seem to be the case with the front loaders ..The prices may have fallen but the quality has changed as well......any one else have some insight on this? ..regards,Bob

Sat, 03/08/2014 - 10:22

by Armando Cobo

Helpful? 0

With all the Political Correctness nowadays, does anyone understands Satire anymore?

Sat, 03/08/2014 - 10:36

Response to Armando Cobo
by Martin Holladay, GBA Advisor

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Your wit was too dry, Armando. I just assumed that your were a sharp dresser.

Sat, 03/08/2014 - 18:47

"Front load washer mold"
by aj builder, Upstate NY Zone 6a

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Another issue, tangled contents, variable wash time, wash times going toward endless if the machine senses not ready for high speed rinse.....

Early adopter issues.... They are improving.

Sat, 03/08/2014 - 19:32

Edited Sat, 03/08/2014 - 19:49.

Also, a bigger issue
by Robert Connor

Helpful? 0

I assumed Armando has kids because he refers to them. Having one child will much more than wipe out any savings of energy anyone does with efficient cars and appliances. In fact, the worst gas guzzling, SUV driving, steak every day eating, fly on vacations and cigar smoking single guy has less of a carbon score than a father. Why do all these energy improvements if you go and have multiple kids?

It would be interesting to know about the carbon footprint of different. Cotton uses a lot of water to create and has to be ironed. But back in the 70s there was a lot of polyester and isn't that made out of oil. But leisure suits never needed ironed and John Travolta's white polyester suit from Saturday Night Fever is still in some closet in Hollywood, without a wrinkle. Also, I think dry cleaning must be an environmental disaster so do people who have to dress up in offices do worse for the environment.

Martin, I know you don't have much of a carbon footprint because after your avatar, you are so not a sharp dresser!

Sun, 03/09/2014 - 06:44

Edited Sun, 03/09/2014 - 06:48.

Mold problems in some front-loading washers
by Martin Holladay, GBA Advisor

Helpful? 0

Thanks for alerting me to the problem of mold growth in some models of front-loading clothes washers. I was unaware of the issue before your comment sent me Googling.

Here is the summary: Some front-loading washers sold between 2001 and 2008 had design problems that allow mold to grow in the machines. If you are worried about this problem, don't buy a used front-loader; buy a new one.

The good news is that appliance manufacturers have made design changes that experts say have eliminated the mold issue in the newest machines.

The best article on the issue was published by Consumer Reports. Here is the link: How to prevent smelly mold buildup in front-loading washers.

For more information on a class-action lawsuit -- apparently unsuccessful -- see Is your washing machine growing hidden mold?

Kimberley Mok, a blogger at the Treehugger website, shares her experience with front-loader mold problems and expensive repairs in an article called Lawsuit over front-load washers may drive consumers back to energy-wasting models.

Mon, 03/10/2014 - 13:54

Mold issues: two anecdotes
by Keith H

Helpful? 0

Until recently I owned a ~2005 Kenmore (made by Frigidaire I believe). It consistently experienced moldy odor. Clothes could not be left in it after the cycle for even an hour, if you cleaned the pump and evacuation tubing of the machine (required at least 2x a year) you would find a brown bio-film sludge. To call it mold would be a kindness. I now own a 2010 GE. It seemed great initially. Eventually the pump burned out and the service tech replaced it with a whirlpool pump (looked like the same design as the frigidaire) for availability and cost. And lo, the mold odor returned.

The upshot here is that I suspect the cheaper end of the front loaders are still experiencing the same issues. Caveat emptor.

Mon, 03/10/2014 - 13:55

New small agitator high efficiency top loaders
by Keith H

Helpful? 0


During your research, did you find any good information on the energy use of the new 'high efficiency' top loaders or their wear and tear factor on clothing?

Mon, 03/10/2014 - 14:00

AJ: Tangled contents is a red herring + clothing life energy
by Keith H

Helpful? 0


Assertions that front loaders somehow tangle or damage your clothing are a red herring. I've seen it with sheets, nothing else.

IMHO, front loaders are an amazing upgrade in terms of clothes durability. SWMBO will not allow a top loader anymore because a decade of front loaders means that her business clothes don't really wear out anymore.

Given what has to happen to produce clothing these days: extract oil from ground, make clothes (polyester) or pesticides (cotton), ship raw material to asia/etc, produce, ship back to US, ship to shiny lit heated retail space, drive to said store to purchase, then the whole discard waste stream. it seems to me that durability of clothing (at least for adults) should probably trump energy use of the machine.

Mon, 03/10/2014 - 14:32

on a few different thing here ...
by Jin Kazama

Helpful? 0

about MOLD issues ..
MOLD is present in older models only if you do not wipe the front door seal area and leave the door closed all time ..
Leave the front door open and it will help greatly.
We've been using BOSCH front loader for 10 years + without any failures/problems.
They are design from factory to last 10 yeasr @ 4 cycles per week or more .

Then, why no mention of the make up air for the dryer ??
At -25c outside temp must hurt alot.
Anyone ever run calcs on that factor ?

Mon, 03/10/2014 - 14:56

Edited Mon, 03/10/2014 - 14:58.

On lost quality time
by Eric Sandeen

Helpful? 0

Satire or no, there's no reason to lose quality time w/ the children over a clothesline. Time spent outside, with children helping do household chores in the fresh air, sounds like excellent quality time to me!

Tue, 03/11/2014 - 15:00

LG Washer/Dryer Combo
by Kevin Dickson, MSME

Helpful? 0

I have to mention my current favorite washing machine, which includes a ventless dryer.


1. Saves valuable space in the house
2. Saves having to move the laundry from the washer to the dryer
3. No vent required

1. Historically, these combos don't dry as well as people expect, but this one gets good marks
2. Although it is a condensing dryer, it would be more efficient if it were a heat pump condensing dryer.

Wed, 03/12/2014 - 20:57
by Sean McGrath

Helpful? 0

The web site says: "3200 rpm spin dryer gets clothes nearly dry in only 2-3 minutes. removes much more water and detergent from the clothes than a conventional washing machine spin cycle. much gentler on clothes compared to a tumble dryer and nearly 100 times as energy efficient. highly portable, only 22 lbs. and no hookup required."

They don't say how much energy it uses. For a load washed in a 25 year old top loader I get 1/2 to 1 quart of water extracted per load and my old gas dryer time is less than half.

Thu, 03/13/2014 - 00:02

by Ed Dunn

Helpful? 0

I bought my first front loader in about 1997. It lasted 10 years before it became completely unrepairable. The repairman told me that the front loaders he noticed typically last only that long versus the top loaders going twenty. Not very sustainable. Anyone else run into this problem?

Tue, 03/25/2014 - 14:31

Edited Tue, 03/25/2014 - 14:32.

Stats are off the Charts
by Daniel Gonzalez

Helpful? 0

When it comes to buying appliances that cost this much, I believe people should be taking a little longer to buy them. Now according to your stats, I simply find outstanding that

1. the energy saving machines don't save on electricity, just mostly on the water (they should be more explicit).

2. the dryers are the bulk of the energy consumption.

I'm wondering what are things that can be put in place besides putting clothes on a line to dry that will save a little bit on time but also not waste so much energy. I know that when it comes to washers, I found that front loading has been (as of lately based again on your data) better than the top loading washers when it comes to energy. Thank you for writing this article, quite insightful!

Sat, 03/29/2014 - 06:43

I just bought a new washer
by Carl Fosler

Helpful? 0

I just bought a new washer and dryer to replace my 25 year old units, but I normally only do one or two loads a week, so I'm sure that help extend their life. I replaced my washing machine with one of the Consumer Reports better rated machines, a EnergyStar 3.7 cu. ft Kenmore steam front-load washer #41372, with Accela-Wash™ option (Accela-Wash wash cycle is 38 minutes instead of the standard 60 minutes). As I understand it, this model is based on LG's Turbo Wash models but with a better interface. After checking the EnergyGuide, my yearly cost at my usage level was only a couple of dollars a year, but I worry that the machine "phantom load” might be more then my usage cost, so I hook up my KillaWatt to see. I found that after I turn the washing machine off, I had a "phantom load” of 7 watts, but I found that it turn itself off after 75 seconds. I just check, and found that the machine has NO measurable “phantom load” since the last wash more then a week ago, so it looks like in this model, they have fixed the "phantom load" problem. Not sure why it delays shutting off for more then 60 seconds, unless power is needed in other models that use the same electronics. Too bad I didn't put the KillaWatt on my old washing machine before I replaced it, so I would know how much I'm really saving.

Another factor that Martin doesn't talk about, new machine actually measure the size of the load at the start of the cycle, and then change the washing cycle depending on the load size. I have only done two loads since I put the KillaWatt on, but they only used 0.11 and 0.09 kWh per load, (both more then half, second smaller then first load), so it seems to use less energy depending on the load size.

I bought the matching Kenmore dryer, so I'm guessing it has the same more then 60 seconds delay before shutting off, but since it an electric dryer with 220 hookup, I don't have a way to measure it power usage.

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