Before you start shopping, decide how big a washing machine you need to meet your household's needs. Don't forget to consider the amount of physical space you have available for the machine.

"ENERGY STAR® qualified clothes washers cut energy and water consumption by over 40% compared to conventional models. Depending on your local utility rates and your household’s usage habits, this can save your household about $50 per year in energy and water bills."

Washers come in two basic designs: front-loading or re-designed top-loading designs—see http://www.energystar.gov/index.cfm?c=clotheswash.pr_front_top  for descriptions. Models that have earned ENERGY STAR® are available in both designs. To search for federal tax credit information, special offers, and rebates from ENERGY STAR® partners, visit: http://www.dsireusa.org/library/includes/map2.cfm?CurrentPageID=1&State=FL&RE=0&EE=1 and http://energystar.gov/index.cfm?fuseaction=rebate.rebate_locator.

In addition to size, design, and certification, you still need to know just how much energy a clothes washer uses per cycle in order to make an informed decision. The U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy requires the industry to thoroughly test and report the energy usage of all appliances. Clothes washer energy consumption is measured in two ways.

• MEF (Modified Energy Factor) measures the energy used during the washing process, including washing machine energy consumption per cycle, hot water energy consumption, and dryer energy required for the removal of the remaining moisture in the wash load—the higher the MEF, the more energy efficient the clothes washer. At the time of this writing, ENERGY STAR® qualified models manufactured after January 2007 must meet the current minimum MEF standard of 1.72.

• WF (Water Factor) measures the gallons of water used per cycle per cubic foot (for example, a 3.0 cubic foot washer using 27 gallons per cycle has a water factor of 9.0). The lower the WF, the less water the machine uses. By July 2009, ENERGY STAR® qualified washing machines will be at least 43% more efficient than the current federal energy efficiency standards and have a maximum WF of 7.5. By January 1, 2011, ENERGY STAR® qualified washing machines will be 59% more efficient than mandated energy standards and will have a maximum WF of 6.0 (U.S. Department of Energy, March 2008).

The yellow EnergyGuide labels that appear on all new washing machines include information on the energy usage of the product, energy usage comparisons with similar models, and estimated annual operating costs. The EnergyGuide label was updated in 2007 to feature estimated annual operating costs more prominently (Federal Trade Commission, August 2007).  When comparing EnergyGuide labels, be sure to look at the tub capacity printed on the label. Choose a washer with the tub capacity that meets your needs—standard sizes for residential use typically range anywhere from 2-3.5 cubic feet.

Source: Wendell A. Porter, Hyun-Jeong Lee, and Kathleen C. Ruppert, Energy Efficient Homes: Laundry Area UF/IFAS FCS3260, 2008