The average American washer swallows 40 gallons per load—more than one-fifth of the average total household water use. Exceeded only by the refrigerator, conventional washers and dryers top the list for home energy consumption. Fortunately, it’s easier to green a laundry room than to get rid of a blueberry stain.

Washing machines: The laundry list

If your old washer has died, the best replacement is one backed by the U.S. Environmental Protection Agency Energy Star program (www.EnergyStar.gov). It will use 40 percent less energy and about half the water of a standard model. A front-loading, Energy Star-labeled washer saves even more.

Front-loading, or horizontal-axis, washers are more efficient because gravity helps distribute water and then pulls it back out of clothes. Less-wet clothes take less time in the dryer. Front loaders also require less detergent. The downside is that front-loaders generally cost a few hundred dollars more. If you’re tempted to buy a new “super efficient” top-loading model, know that most of them still don’t compete with front-loaders in efficiency or performance, but cost almost as much.

Two terrific tools for gauging washer efficiency are the Water Factor (WF) and the Modified Energy Factor (MEF). The WF measures the water used per cycle in gallons per cubic foot of washer space; for example, a 3-cubic-foot-capacity machine that uses 27 gallons per cycle has a WF of 9. The lower its WF, the higher the machine’s efficiency.

The MEF, which replaced the less comprehensive Energy Factor in 2004, considers energy used not just by the machine but also by the water heater for each cycle and by the dryer to remove the remaining moisture from the clothes. It’s a complex calculation that makes it simple for consumers: The higher the MEF, the more efficient the washer. The Environmental Protection Agency also has a “WaterSense” label it awards machines with great water efficiency.

Before 2007, the minimum MEF for an Energy Star washer was 1.42, and no WF was required. Now the MEF must be higher than 1.72 and the WF lower than 8. The WF and MEF are not always listed on the label, so you may want to research them before making a purchase.

Compared with an old 1994 model, a new Energy Star washer will save you about $110 a year on utilities. If you’re wondering how long it might take to recoup in utilities the extra money spent on a front-loading machine, the Energy Star website also has a handy Savings Calculator tool to help you compare models (see Resources on page 73).