The beauty here is the bulk of your cost to operate a washing machine consists in heating the water. Since our mythical homeowner is both super insulated and using a solar water heater, we can wash clothes for next to nothing:

http://www.energystar.gov/index.cfm?c=clotheswash.pr_clothes_washers

Residential Clothes Washers

Want to save money and protect the environment? Ask for ENERGY STAR…

An ENERGY STAR qualified clothes washer can save you $550 in operating costs over its lifetime compared to a regular clothes washer. ENERGY STAR qualified washers are also better for the environment because lowering energy and water use means less air pollution from power plants and less water going to waste.

• Lower your utility bills and protect the environment

  Choosing an ENERGY STAR qualified clothes washer over a standard model can lower your utility bills, save energy, and save water. Qualified models perform more efficiently than standard models without sacrificing performance.

• Save more than money

  An ENERGY STAR qualified clothes washer can save you time and help lengthen the life of your clothes.

• Learn what new technology makes washers energy-efficient

  New technological advances have allowed ENERGY STAR clothes washers to use significantly less energy and water.

• Buy with confidence using these purchasing tips

  Make sure you choose a clothes washer that is the right size and model, and has the appropriate features to fit your needs.

• Get the best performance from your ENERGY STAR qualified washer

  Take advantage of simple energy-saving tips and best practices to save more money on your utility bills and avoid maintenance.

• Search for rebates and tax credits

  Find local rebates and tax incentives available for ENERGY STAR qualified products in your area.

Locate a store nearby that sells ENERGY STAR qualified clothes washers

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Here is one of many reviews. IN FACT I am shocked that you have to look for most of the residential stuff we have reviewed so far. You type energy efficient washing machines into google and you get hundreds of sites. I swear there is something wrong with this country sometimes.

http://www.consumersearch.com/www/house_and_home/washing-machine-reviews/

Washing Machines Reviews

 GE WJRE5500GWW

Best top-loading washer.

While some basic top-load washers have plummeted in performance testing when it comes to cleaning ability, the GE WJRE5500GWW gets good scores for washing performance and costs less than a high-efficiency front loader. This model has a 3.5-cubic-foot capacity with a stainless steel tub and the usual wash cycles. It uses rotary dial controls. Also included is an automatic load balancer – a feature that’s starting to disappear on less expensive washing machines. The most common owner complaint is that this washer’s spin cycle isn’t particularly strong, so clothes may need more drying time.

Fisher & Paykel Intuitive Eco IWL16

Most reliable high-efficiency top-loader.

There are now many high-efficiency top loaders on the market — these replace an agitator with some other technology that uses less water and energy. Unfortunately, we read very mixed owner reviews for most of these, including the Maytag Bravos and Whirlpool Cabrio. Owners seem far happier with the Fisher & Paykel Intuitive Eco IWL16, which uses less energy than a conventional top loader, yet gets clothes as clean or cleaner with less noise. Three spin speeds let you customize how much water is wrung out — the 1,000 rpm speed is great for towels and jeans, meaning they’ll need less drying time. Unlike other high-efficiency washers, you can use regular detergent with the Intuitive Eco.

Frigidaire GLTF2940F

Top budget front-loader.

Front-loading washing machines clean better, are more energy efficient and use less water than conventional top-loading machines. The trouble is that reliability is often iffy. The Frigidaire GLTF2940F is one of the cheapest front loading washers available, yet its scores for efficiency and cleaning ability are as good as some models that cost twice as much. The Frigidaire is a bargain if you want a front-loading washer, but we did read some complaints about water building up in the rubber door seal causing odors — a very common complaint with most front loaders. Reports on reliability are mixed, but in line with what we’ve seen for most washers.

LG SteamWasher WM2688HNMA

Best front-loading washing machine.

Unlike most other machines, the LG SteamWasher offers an important extra: two steam cycles. One steam cycle prepares clothes for ironing, while the other sanitizes them for a longer period, which reduces lingering odors. The LG has a large-capacity 4-cubic-foot stainless steel washtub, and its faster 1,320-rpm spin cycle gets more water out of laundry (which means less drying time). This machine also features a delay cycle that can put laundry on hold up to 19 hours, and the wash cycle can be monitored remotely via computer. While expensive, the LG TROMM gets better owner-written reviews than other front-loading washing machines.

July 8, 2008 Update We found the most thorough, credible and up-to-date washing machine reviews at Consumer Reports. Its website also has a moderated discussion board that allows subscribers to ask questions and exchange information about washing machines. Its methodical testing in several categories helps buyers to choose the best washers currently on the market. Although we also found excellent hands-on evaluations and extensive testing of washers at Australia’s Choice and Britain’s Which? magazines, most of the models in these two publications are not available in the U.S., so these articles are of less help to American consumers.Good Housekeeping magazine used to be a good place to find reviews on major appliances, but we didn’t find any recently written information on washing machines. However, we have found an increasingly large number of owner-written reviews for washing machines, which are extremely helpful when it comes to gauging noise level and reliability. Sears.com, BestBuy.com and HomeDepot.com are all great places to check for user reviews on a given washing machine.In January 2007, the U.S. Department of Energy phased in tougher efficiency requirements for washing machines. New washers are required to use 21% less energy. While that seems great in concept, the end result has been dirtier laundry. Consumer Reports has the most balanced information on the effects of these requirements. For many conventional top-loading washing machines, models must now use less water and lower wash temperatures, which can affect performance. Although we found some heated debate on this topic, Consumer Reports is the only publication that backs up its opinions with product testing.

 In Consumer Reports’ testing, the least expensive type of washing machine – traditional top-loaders with agitators – had a hard time cleaning clothes as well under the new efficiency mandates. Front-loading washers and some alternative top-loaders use a different technology than a traditional agitator, and are not as impacted by the new laws. To get the same level of cleanliness, users may need to do more pre-treating of stains.

We found many websites that rate washing machines based purely on efficiency, but with no performance testing. These include the American Council for an Energy-Efficient Economy (ACEEE), EnergyStar.gov and the Consortium for Energy Efficiency (CEE). All of these websites have good explanations of technology and related articles despite the lack of performance testing

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AND many more useful sites:

www.saveenergy.about.com/od/energyefficientappliances/p/eneffwashingmac.htm

www.staber.com

www.ecobusinesslinks.com/appliances_energy_efficient.htm

www.ftc.gov/bcp/edu/pubs/consumer/alerts/alt070.shtm 

www.veggierevolution.blogspot.com/2008/07/energy–efficient-and-water-saving.htm

www.ehow.com/how_2140467_buy-energy–efficient–washing–machine.html

www.thedailygreen.com/green-homes/latest/green-remodeling-laundry-rooms-460212

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