The Natural Resources Defense Council estimates a new Energy Star refrigerator can save consumers $100 a year if it replaces a "vintage model" from the 1980s. Of course, consumers can save much more and do the environment an even bigger favor by giving up the refrigerator entirely. But it's not the only hog in the house.

    A new washing machine can save $110 a year and use half as much water as one manufactured in 1994. The NRDC predicts savings of $25 a year from dishwasher replacement and $14 a year for each new window air conditioner.

     More precise estimates are available from GreenerChoices.org, a Consumer Reports Web site where consumers can enter model numbers and utility rates to compare the energy cost of current appliances to the expected cost of replacements. Consumer Reports, the NRDC, and the EPA suggest many ways homeowners can save energy, money, and the environment by replacing or maintaining appliances:

 Water Heaters

New water heaters can save consumers $103 per year, according to Consumer Reports. Short of replacing a water heater, you can save energy by reducing the temperature — for every 10 degrees, CO2 emissions drop 3-5 percent, or 733 pounds annually. New water heaters have added insulation, but you can achieve similar effects by wrapping an old one with a $35 insulating jacket.

 
Washing Machines

Front-loading washers usually use less water than top loaders because they tumble clothes through the lower half of a drum instead of submerging them entirely. However, the latest Energy-Star top-loaders rival front-loaders for efficiency. “Look for a washer with adjustable water levels,” urges the NRDC. “This gives you the option of using less water to wash small loads.”

Clothes Dryers

Dryers with moisture sensors save energy by shutting down as soon as clothes are dry. The clothesline remains the most economical and environmentally friendly dryer.

 
Air Conditioners

A new central air conditioner can reduce CO2 emissions by about 1,540 pounds annually, according to Consumer Reports, and save a homeowner about $118 a year. Setting the thermostat three degrees warmer will prevent 378 pounds of CO2 emissions each year.

Dishwashers

Energy-Star dishwashers use 25 percent less energy than older models, saving up to $100 per year on energy bills. Experts recommend running the dishwasher with a full load and drying dishes by hand instead of using the heat-dry feature. Drying by hand—now that's dedicated activism.

 
Stoves and Ovens

Electric ranges use less energy than gas ranges but may cost more to operate because of higher electric rates, according to the Consumer Guide to Home Energy Savings. If the electricity comes from a coal-fired power plant, it may also emit more carbon than natural gas. Microwaves use only about 20 percent as much energy as conventional ovens.

Instead of sending an old appliance to the landfill, find an appliance recycler in your area by visiting RecycleMyOldFridge.com or Earth911.org.

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