Making Dish Duty Greener
Greentips: July 2010
Many people buy dishwashers to save time at the sink, but dishwashers can also save water, energy, and money. According to a European study of dishwashing habits, hand-washing a full load of dishes consumes an average of 27 gallons of water. Conventional dishwashers average 6 to 10 gallons per load, but an Energy Star-rated dishwasher uses less than six gallons (some use as little as 1.5 gallons). The Department of Energy estimates that, compared with hand-washing, an efficient dishwasher can save you more than $40 in energy costs, 5,000 gallons of water, and 230 hours of personal time per year.
When shopping for an Energy Star dishwasher, consider models with these features to maximize its efficiency:
- Soil sensors that adjust hot-water use based on the dirtiness of your dishes
- Removable or height-adjustable top racks that can accommodate larger dishes that would normally have to be hand-washed
- A half-load cycle that washes one rack’s worth of dishes if you need them cleaned before the machine is fully loaded
- A booster heater that raises water temperatures to 140 degrees Fahrenheit, which allows you to lower your household water heater to 120 degrees (each 10-degree reduction can save you 5 percent or more on annual water-heating costs)
You can further reduce energy and water use by:
- Scraping food from dishes instead of rinsing them, which the Department of Energy estimates can use up to 20 gallons of water per load. If you can’t fill your dishwasher right away, you can use the “rinse and hold” feature if needed to keep foods from sticking—this still uses less water than hand-rinsing.
- Turning off the heated-dry option, which increases a dishwasher’s energy consumption by 15 to 50 percent. Or, simply turn the dishwasher off after the rinse cycle and open the door to air-dry the dishes.
- Running the dishwasher only when full (but leaving room between dishes for water to circulate).
If a dishwasher is not an option, you can still save energy and water while washing dishes by filling a dishpan or sink compartment with warm soapy water and another with cool rinse water. Installing a faucet aerator, which minimizes water flow, can also reduce water consumption.
